ASM ORAL NOTES 1 | Knowledge Of Sea

What is Ice ? Which ships can go to ice region?

Ice involves in cold waters, where ice is a hazard to the safety of . The presence of sea ice requires a ship to exercise caution, for example by avoiding icebergs, slowly sailing through a lead, or by working with an icebreaker to follow a course through the ice to a destination.

Only ice class ships can operate in Ice region. Ice Class means the notation assigned to the ship by the Administration or by RO showing that the ship has been designed for in sea-ice conditions. Following are the categories as defined under Polar Code:

• Category A ship means a ship designed for operation in polar waters in at least medium first-year ice, which may include old ice inclusions.
• Category B ship means a ship not included in category A, designed for operation in polar waters in at least thin first-year ice, which may include old ice inclusions.
• Category C ship means a ship designed to operate in open water or in ice conditions less severe than those included in categories A and B.

These ships must comply with the Polar Code and have on board a valid Polar Ship Certificate and a Polar Water Operational manual (PWOM).

Vessel has received orders to transit ice infested waters. What are your actions / checks as a Master?

• Check if the voyage is allowed as per Charter Party limits i.e. IWL / INL.
• Check if vessel is suitable for executing the voyage safety depending the time of the year, weather conditions in the area, ice class of the vessel, etc.
• Carry out a management meeting to discuss the voyage intended.
• Carry out a risk assessment for the voyage contemplated.
• Obtain ice reports and ice warnings and other weather forecasts from all available sources.
• Check if vessel can perform the voyage on her own or assistance of ice breakers will be required.
• Check sufficient FW, provisions, fuel and stores (winter gears, etc) are available as voyage may be longer than expected.
• Check all equipments are in order. Ensure latest charts are obtained and updated.
• Carry out a Bridge team meeting to discuss the passage plan.
• Carry out a meeting with all the crew members to discuss personal safety and cold weather precautions to be taken on deck and engine room.

As a Master, what will be your concerns with regards to communication in Polar Regions? Which communication equipments are onboard for sea area A4?

Concerns with regards to communication:

• Current maritime digital communication systems not designed to cover Polar waters.
• High latitude affects communication systems and the quality of communication.
• Due to the remoteness of the area, there will be limited SAR facilities and limited communications capability, with the potential to affect incident response.

Communication equipments are onboard for sea area A4:

• SOLAS Chapter IV, Regulation 7- Radio Equipment General

VHF with DSC and radiotelephony
SART
NAVTEX
EPIRB

• SOLAS Chapter IV, Regulation 11 – Radio equipment: Sea areas A1, A2, A3 and A4

In addition to above,

MF/HF with radiotelephony and DSC and NBDP
Means of initiating the transmission of ship-to-shore distress alerts by a radio communication service other than HF operating through
a) the polar orbiting satellite service on 406 MHz (such as satellite EPIRB) and,
b) the lnmarsat geostationary satellite service by a ship earth station.

What are the hazards of ice-accretion? What steps will you take to prevent or reduce ice-accretion?

Hazards of ice-accretion:

• Centre of gravity of the ship is raised with a corresponding reduction in stability.
• The added weight of ice leads to an increase in displacement and hence to a reduction in freeboard and buoyancy.
• Heel due to icing only on one side due to beam wind.
• It can cause radio and radar failures due to the icing of aerials.
• Visibility from the bridge may also be affected
• If ice is not removed, there is a great danger of instability and possibly capsizing.

To prevent or reduce ice-accretion:

• Keep away from areas of strong wind and low air temperatures as far as possible.
• Seek immediate shelter in a harbor or downwind of a land mass to minimize spray.

• If shelter is not available, then steam downwind to minimize sea spray on the ship’s deck and superstructures. (upwind for certain ships)
• “Ice-phobic” (ice fearing) coatings can be applied.
• Physical removal of ice using tools such as baseball bats, large wooden mallets, ice scrappers, shovels, spades, picks, etc.
• Use of chemicals such as Rock Salt (Sodium Chloride), Calcium Chloride, Urea, Ethylene Glycol and other light de-icers including alcohols.

What problems will you face with regards to in higher latitudes?

• High latitude affects systems and communication systems.
• Ice may be encountered which may make difficult.
• Remoteness and possible lack of accurate and complete hydrographic data and information.
• Proximity to the North Magnetic Pole has an effect on the charts that are supplied and the instruments that are used with them.
• Magnetic compass is no longer reliable as a direction measuring device.
• Satellite coverage will gradually decline and then become unusable.
• False echoes may be given by ice passing underneath the echo sounder.
• Reduced availability of al aids with increased potential for groundings
• Limited communications capability.
• Extended periods of darkness or daylight may affect .

What is sea trial?

Every shipyard after constructing and launching a vessel performs a set of tests to ensure that all systems of the vessel meet the corresponding requirements assigned by the owner under the contract and at the same time conform to the rules and regulations of the approving classification society. This series of tests are clubbed under the heading Sea trials which simply imply trials carried out at the sea after final outfitting and launching of the vessel just before delivery.

Following are some of the tests that are carried out during sea trials:

Draft measurement – in case the ship is not floating at the required draft it is corrected since the very purpose of speed trials is to prove guaranteed speed at a particular draft.
Anchor test – It is performed to check the functioning of the entire anchoring mechanism.
Steering Gear Test – Hard over to hard over at full speed is tested. Also, emergency steering is tested at half ahead speed using the Emergency generator.
Main Engine Endurance Test – The M/E is run for about 6 straight hours at full rated RPM in order to test its performance at full load. It is initially run on DO and then FO and again on DO. This is to check the changeover process from HFO to DO.
Speed trials – These are carried out to check the speed of the vessel at the required draft. It is carried out at a minimum of 3 powers – such as 75%, 85%, 100% MCR or as per the contract. The speed is measured using the GPS by running the ship in two opposite directions.
Astern running – vessel is run in the astern direction at about 70% ahead MCR by running the engine in reverse direction.
Crash Stop Test – In this test, the stopping ability of a vessel is assessed.
Turning circle test – It is carried out to measure the diameter of the circular path which the vessel starts to traverse as soon as the rudder is put hard over. The vessel is run to complete one circle and the diameter is measured using GPS.
equipments – Operation of equipment such as RADAR, communication systems, etc. are also checked during sea trials.
Black Out Test – There is a complete blackout on board as all the main generators are shut down and the automatic starting of Emergency Generator is observed.

How to ensure OOW does not sleep during his watch and keeps a good anti piracy watch?

• Emphasize good watch keeping during Bridge team meetings.
• Emphasize proper lookout in your night orders and standing orders.
• Take special care to ensure everyone is adequately rested and not fatigued.
• Ensure proper functioning of BNWAS and regular testing of the alarms.
• Ensure all bridge equipments for lookout are adequately maintained and available.
• Instruct all OOW‟s to call self without any hesitation in case they are feeling sleepy or
unwell.

Which are the MARPOL annexes relevant in passage planning?

• Annex I – If vessel intends to do tank cleaning or entering or exiting special areas.
• Annex II – If vessel intends to do tank cleaning or entering or exiting special area.
• Annex IV – If vessel is entering special area or if local regulations do not allow disposal of sewage even through the STP.
• Annex V – If vessel is passing through any Annex V special area.
• Annex VI – If vessel will be entering or exiting the ECA and change-over of fuel is required. Also, sufficient MGO to be available with adequate reserves.

How will you plan GC passage and what are the dangers in GC sailing?

A great circle track is the shortest distance, measured along the earth‟s surface, between two places. A great circle track cuts successive meriians at different angles because the meridians are not parallel to one another. The course, therefore, should change slightly whilst crossing each meridian.

• I will tell my 2nd Officer the limiting latitude depending on the dangers involved with high latitudes.
• I will check the passage and ensure proper courses are plotted on the chart or ECDIS. (Practically, the two points are plotted on the Gnomonic chart and joined by a straight line. The vertex and suitable points are read off the chart and RL courses are plotted on mercator chart from point to point thereby followign the GC track effecively and conveniently.)
• The GC track must not lead the vessel in dangerous waters or over land. In such a case, I will practice composite sailing to limit the maximum latitude, generally to avoid ice or severe weather near the poles.

Dangers involved in GC sailing: If latitude of the vertex is too high, ice, fog, extreme cold and bad weather may be experienced.
.

What are the adverse weather effects and how will you mitigate them?
MSC.1/Circ.1228 gives guidance to the Master for avoiding dangerous situations in adverse weather and sea conditions. It has been brought out with a view to providing masters with a basis for decision making on ship handling in adverse weather and sea conditions, thus assisting them to avoid dangerous phenomena that they may encounter in such circumstances. Adverse weather conditions include wind induced waves or heavy swell.

Adverse weather effects:

• Synchronous rolling or Severe roll motions
• Parametric rolling
• Damage to cargo or loss of cargo or shift of cargo
• Damage to equipment onboard
• Injury to persons or loss of persons onboard
• Capsizing of the ship due to violent rolling or cargo shift
• Surf-riding and broaching to in following or quartering seas.
• Combination of any of the above Ways to mitigate them:
• For surf riding or broaching to, alter the course and/or speed so that the angle of encounter is out of the range 135°<α<225° and the ship speed is lesser than (1.8 √L / cos (180-α) (knots).
• For synchronous and parametric rolling,

Reduction of speed – Speed can be reduced to change the wave encounter period thereby breaking the synchronization between the ship‟s natural period of roll and wave encounter period.
Alteration of course – Vessel‟s course must be altered to a more favourable course to ease the vessel‟s motion by breaking the resonance between period of wave encounter and ship‟s natural rolling period.
Heaving to, preferably in lee of a land mass, to allow weather to pass, if possible
• Filling up all slack tanks to minimize the FSE will also help in improving stability.
• Before the adverse weather is encountered, heavy weather ballast may be taken in
designated tanks to lower „G‟ and improve stability.
• Weather routeing services – these may be used to identify the best available route considering the expected and prevalent weather and thereby making amendments to the passage plan

Describe the bridge visibility criteria.

SOLAS Chapter V, Regulation 22: Bridge Visibility
Ships of 55m or more in length constructed on or after 1 July 1998, shall meet the following requirements:

The view of the sea surface from the conning position shall not be obscured by more than two ship lengths, or 500 m, whichever is less, forward of the bow to 100 on either side under all conditions of draught, trim and deck cargo.
No blind sector, caused by cargo, cargo gear or other obstructions outside of the wheelhouse, forward of the beam which obstructs the view of the sea surface as seen from the conning position shall exceed 100. The total arc of blind sectors shall not exceed 200. The clear sectors between blind sectors shall be at least 50. However, in the view described in .1, each individual blind sector shall not exceed 50.
The horizontal field of vision from the conning position shall extend over an arc of not less than 2250, that is from right ahead to not less than 22.50 abaft the beam on either side of the ship.
From each bridge wing, the horizontal field of vision shall extend over an arc of at least 2250, that is from at least 450 on the opposite bow through right ahead and then from right ahead to right astern through 1800 on the same side of the ship.
From the main steering position, the horizontal field of vision shall extend over an arc from right ahead to at least 600 on each side of the ship.
The ship’s side shall be visible from the bridge wing.
The height of the lower edge of the bridge front windows above the bridge deck shall be kept as low as possible. In no case shall the lower edge present an obstruction to the forward view as described in this regulation.
The upper edge of the bridge front windows shall allow a forward view of the horizon for a person with a height of eye of 1,800 mm above the bridge deck at the conning position when the ship is pitching in heavy seas. The Administration, if satisfied that a 1,800 mm height of eye is unreasonable and impractical, may allow reduction of the height of eye but not to less than 1,600 mm;
Windows shall meet the following requirements:
a) To help avoid reflections, the bridge front windows shall be inclined from the vertical plane top out, at an angle of not less than 100 and not more than 250.
b) Framing between windows shall be kept to a minimum and not installed immediately forward of any work station.
c) Polarized and tinted windows shall not be fitted.
d) A clear view through at least two of the bridge front windows and, depending on the bridge configuration, an additional number of clear-view windows shall be provided at all times, regardless of weather conditions.

How will you carry out briefing and debriefing of passage plan and who all will be involved?

• For the briefing, I will call all the Bridge team members on the Bridge to carry out the Pre-arrival bridge team meeting. The members will include all officers, lookouts, helmsmen and also Chief Engineer in case fuel changeover or other requirements are to be discussed.
• I will discuss the passage plan, with special emphasis on the approach, anchorage area, traffic expected, reporting requirements, routeing measures, VTS and other local regulations.
• I will discuss the pilotage area, berth details, weather forecast, contingency anchorage, abort point, no go areas and dangers, etc.
• I will highlight the call master point, when notice to be given to E/R, engines and steering to be tried out, etc.
• I will highlight special aspects of the passage such as entering / exiting special areas, any fuel changeover requirements, local regulations, etc.
• I will ask for inputs and experiences of the Bridge team members and ask for any suggestions for improvement and anything missed out by me in the discussion.

• For the debriefing, I will call the same Bridge Team members and discuss the passage completed, if anything could be improved, any good practices identified and take feedback from all the members.

State the UKC policy of your Company and what all factors UKC depends upon?

UKC Policy of my Company:

• For ocean and coastal passages outside shallow waters, minimum UKC must be atleast the vessel‟s maximum static draft.
• In shallow waters (waters where UKC equal to ship‟s maximum static daft cannot be maintained), rivers/port waters, SBM, anchor – minimum UKC must be 10% of the maximum static draft or ONE meter, or as per local/port requirement, whichever is greater.
• At berth, the minimum UKC must be 1.5% of the ship‟s extreme breadth or 0.3m or as
per port/local requirement, whichever is greater.

(UKC to be calculated as per Company Passage Plan Form and based on Dynamic conditions i.e. including squat, roll, pitch, heave, effect of density of water, etc. Controlling depth must be calculated taking into account height of tide, chart accuracy (CATZOC), etc)

UKC depends on the following factors:

• Draft and displacement of the vessel including Hog or sag, if any.
• Minimum charted depth available and chart accuracy
• Squat and the factors that affect squat mainly ship‟s speed.
• Increase in draft due to heaving, pitching and rolling motions.
• State of sea and swell
• Increase in draught due to change of water density
• The predicted height of tide
• Profile of the seabed – i.e. sand waves, pipelines, obstructions etc.

Explain the full procedure for taking a star sight.

• From the almanac, calculate the ship‟s time (SMT) for nautical twilight. (LMT-Long- GMT-ZT-SMT)
• Using the Star Finder (NP 323) identify three stars that are well separated atleast by 60 degrees. This must be done well before the nautical twilight time.
• Find out the approx. azimuth and altitude for these stars for the time of observation using the Star Finder.
• At the time of observation, set altitude on the sextant and look at the horizon in the direction of the approx azimuth and quickly note down the timings and altitude of the three stars.

• Calculation is then done by the Intercept method, applying run if required. The fix is
the point of intersection of the three PL‟s so obtained.

How to use the star finder for taking a star sight?

Star finder is used to find a star who‟s azimuth or altitude is measured. It can also be used to find the approx azimuth and altitude of the stars that are selected for star sight so that the sextant can be set to that altitude and the user can directly look at the horizon in the direction of the approx azimuth.

a) From Almanac, find GHA γ for the time of observation.
b) Calculate LHA γ by applying Long E (+) or Long W (-)
c) Select the template of the latitude that is nearest to your present latitude and place it on the star diagram. (NH or SH)
d) Align the arrow on template to LHA γ value on the diagram and ensure that the 1800/3600 line of the template passes through the pole of the chart and the „+‟ mark is placed on the present latitude of the ship.
e) From the template, read the approx altitude and azimuth of any star selected for star sight.

The red lines are of the transparent template that is placed on top of the Star Diagram. At Point A, we see that the 180/360 line of the template is in line with the North Pole as shown on the Star Diagram.

At Point B, we see that the „+‟ mark is aligned with vessel‟s present latitude i.e. 27deg.

At Point C, the numbers indicate the altitude of the star. (Altair =350)

At Point D, the numbers indicate the azimuth of the body. Template will tell you whether to use the inner or outer figures depending on whether you‟re in NH or SH. (Altair = 2320)

Which is the preferred method for star sight calculation?

Intercept method is preferred for star sight calculations. Since we will take the three sights in quick succession, we use the same DR position and plot all three azimuths (towards or away as applicable) and draw the 3 position lines and find the fix. This method is faster and easier.

Explain the full procedure of sight calculation.

First sight (Long by Chron)

• Calculate the Sextant altitude of the sun at around 9am SMT.
• Apply Index Error, Dip (HE), Total correction and obtain the True Altitude.

• Calculate value of P using the formula and obtain the LHA.
• Calculate the corrected GHA and obtain the Observed Long.
• Calculate the Azimuth for the time of observation.
• Draw the DR Lat & Obs Long and PL passing through it. PL will be -/+90 of Azimuth.

Second sight (Mer pass sight)
• Calculate Merpass time (SMT).
• Calculate the Sextant altitude of the sun at merpass time.
• Apply Index Error, Dip (HE), Total correction and obtain the True Altitude.
• From True altitude, obtain MZD.
• To the MZD, apply declination to get the Observed latitude.
• PL in this case will be E-W i.e. the Obs. Lat.

Calculation of Fix:
• Apply run on the DR lat and Obs Long obtained from the first sight.
• Plot the newly obtained EP Lat and EP Long on a graph paper and the transferred PL.
• Draw the observed latitude obtained from the second sight.
• The point of intersection between the transferred PL and Obs lat will be the fix.

What do you know about IALA Buoyage system? What is region A & B and which country follows which region?

The International Association of Marine Aids to and Lighthouse Authorities (IALA) is a non-profit organization founded in 1957 to collect & provide nautical expertise and advice. IALA is primarily known for the IALA Maritime Buoyage System with which, they have successfully implemented a harmonized buoyage system.

The IALA Buoyage system consists of the following marks:

Lateral Marks – indicate the edges of a well-defined navigable channel. They are also modified to show where channels divide or preferred route to follow.
Cardinal Marks – indicate position of a hazard and the direction of the safe water.
Isolated Danger Mark – indicates a danger to shipping.
Safe Water Mark – indicates the end of a channel and deep, safe water is ahead.
Special Mark – indicates an area or feature such as speed restriction or mooring area.
Emergency Wreck Marking Buoy – for marking a wreck as a temporary means to indicate hazard.

Each type of mark has a distinctive colour, shape and possibly a characteristic light. Lateral Marks are different for Region A and B. Rest all other marks are common to all places all over the world. The IALA Maritime Buoyage System defines two regions in the world: IALA region A and IALA region B. Region B covers the North, Central and South America, Japan, South Korea & Philippines, while rest of the world belongs to region A.

A cardinal mark is used to signify a danger and show where the safest water can be found. Cardinal marks indicate the direction of safety as a compass direction relative to the mark. They are named after the quadrant in which they are placed. They have distinctive black and yellow markings and topmarks.

Use of Cardinal Marks:

• To show the deepest water on an area on the named side of the mark.
• To show the safe side on which to pass a danger
• To draw attention to a feature in a channel such as a bend, junction or end of a shoal.

{Quick (Q) – 50 to 60 flashes / min} {Very Quick (VQ) = 100 to 120 flashes / min}

What is the meaning of isophase, flashing and occulting?

• Isophase: showing equal periods of light and darkness.
• Flashing: showing longer periods of darkness than light.
• Occulting: showing longer periods of light than darkness (opposite of flashing)

What is group flashing and composite group flashing?

Group flashing is a group of a specific number of flashes repeated regularly. For example, Fl (3) R 15s means red light will flash three times and then again three times. Total time from start of the pattern till the next cycle takes 15 seconds.
Composite group flashing is several groups of a specific number of flashes are repeated regularly. For example, Fl (2+1) W 15s means composite group flashes with 2 white flashes in quicker succession followed by one white flash and the entire cycle (till start of the next two flashes) takes 15 seconds.

Describe isolated danger mark and safe water mark.

What is the new danger mark?

It is known as the Emergency Wreck Marking Buoy. It is not a part of IALA Buoyage, but introduced by Trinity House, the General Lighthouse Authority (GLA) for England, Wales the Channel Islands and Gibraltar. It is to be used in the initial stages of an incident to mark the wreck and is maintained in position until:
• The wreck is well known and has been promulgated in nautical publications.
• The wreck has been fully surveyed and exact details such as position and least depth above the wreck are known.
• A permanent form of marking of the wreck has been carried out.

The buoy has the following characteristics:

• Pillar or spar buoy, with size dependant on location
• Coloured in equal number and dimensions of blue and yellow vertical stripes (minimum of 4 stripes and maximum of 8 stripes)
• Fitted with an alternating blue and yellow flashing light with a nominal range of 4 NM (the blue and yellow 1 second flashes are alternated with an interval of 0.5 seconds. If multiple buoys are deployed then the lights will be synchronized)
• The top mark, if fitted, is to be a standing/upright yellow cross.

You are coming out of a port in Japan. On which side will you keep the green conical buoy?

Japan falls in Region B where Green buoy cannot be conical. Green buoy will be cylindrical, pillar or spar. While coming out, I will keep the green buoy on my starboard. (Since the buoyage direction is for going in. while going in, green buoy on the port side)

Draw the chart symbols for: Flood tide, ebb tide, current in restricted waters, light house, wrecks and historical wreck and any other symbol you know.

What do you know about VTS? Is VTS mandatory?

SOLAS Chapter V, Regulation 12 deals with Vessel traffic services.

• VTS contribute to the safety of life at sea, safety and efficiency of and protection of the marine environment, adjacent shore areas, work sites and offshore installations from possible adverse effects of maritime traffic.
• It is established where Contracting Governments in their opinion feel the volume of traffic or the degree of risk justifies such services.
• Contracting Government planning and implementing such services must follow the guidelines developed by IMO. (RESOLUTION A.857(20)
• The use of VTS may only be made mandatory in sea areas within the territorial seas of a Coastal State.

What is the difference between VTS and VTMS?

VTS

As per IMO Resolution A.857(20) on Guidelines for Vessel Traffic Services;

• VTS should comprise at least an information service which ensures that essential information becomes available in time for on-board al decision-making.
• A VTS may additionally also provide;

A al assistance service -to assist on-board al decision making and to monitor its effects.
A traffic organization service – to prevent the development of dangerous maritime traffic situations and to provide for the safe and efficient movement of vessel traffic within the VTS area.
Or Both.

VTMS

So whereas a VTS may provide only an information service as a minimum (or may provide all three), a VTMS provides an information service and a traffic organization service with its main focus being management of traffic situations. These are established in some of the busiest waters in the world and are making valuable contribution to safer , more efficient traffic flow, and protection of the environment. Traffic flow in busy approach routes, access channels, and harbours can be coordinated safely, in the best interest of port and its users. Incidents and emergency situations can be dealt with quickly. Data from traffic movements can be stored and used as reference information for port administration, port authorities, coastguards and search and rescue services.

What is ship reporting system? Is it mandatory?

SOLAS Chapter V, Regulation 11 deals with Ship reporting systems.

• Ship reporting systems contribute to safety of life at sea, safety and efficiency of and protection of the marine environment. A ship reporting system, when adopted and implemented in accordance with the IMO guidelines shall be used by all ships or certain categories of ships or ships carrying certain cargoes in accordance with the provisions of each system so adopted.
• IMO is the only international body for developing guidelines, criteria and regulations on an international level for ship reporting systems. Contracting Governments shall refer proposals for the adoption of ship reporting systems to IMO. IMO will collate and disseminate all relevant information with regard to any adopted ship reporting system.
• This regulation does not address ship reporting systems established by Governments for search and rescue purposes, which are covered under 1979 SAR Convention.
• Guidelines developed by IMO are given in resolution MSC.43(64) and A.851(20).
Ship reporting systems are mandatory under SOLAS V/11 which states „the master of the ship shall comply with the requirements of adopted ship reporting systems and report to the appropriate authority all information required in accordance with the provisions of each such system‟.

What do you know about ship routeing? Is it mandatory?

SOLAS Chapter V, Regulation 10 deals with Ships‟ routeing.

• Ships’ routeing systems contribute to safety of life at sea, safety and efficiency of and/or protection of the marine environment. Ships’ routeing systems are recommended for use by, and may be made mandatory for, all ships, certain categories of ships or ships carrying certain cargoes, when adopted and implemented in accordance with the guidelines and criteria developed by the organization.
• IMO is recognized as the only international body for developing guidelines, criteria and regulations on an international level for ships’ routeing systems. Contracting Governments shall refer proposals for the adoption of ships’ routeing systems to the Organization.
• The Organization will collate and disseminate to Contracting Governments all relevant information with regard to any adopted ships routeing systems.
• Contracting Governments shall adhere to the measures adopted by the organization concerning ships routeing and do everything in their power to secure the appropriate use of ships‟ routeing system adopted by the Organization.
The objective of ships’ routeing is to “improve the safety of in converging areas and in areas where the density of traffic is great or where freedom of movement of shipping is inhibited by restricted sea room, the existence of obstructions to , limited depths or unfavourable meteorological conditions”.

Routeing systems adopted include traffic separation schemes, inshore traffic zone, roundabout, two-way routes, recommended route, deep water route, precautionary area, area to be avoided, etc. The details of adopted routeing systems are given in IMO publication Ships‟ Routeing which must be referred while making a passage plan.

Ship routeing adopted by IMO is mandatory as per SOLAS V/10 which states, „A ship shall use a mandatory ships’ routeing system adopted by the Organization as required for its category or cargo carried and in accordance with the relevant provisions in force unless there are compelling reasons not to use a particular ships’ routeing system. Any such reason shall be recorded in the ships’ log.‟

Certain routeing measures may be mandatory only for certain categories of ships or when carrying certain type of cargo. Hence, it must be checked and accordingly marked on the chart and in the passage plan.

Resolution A.572(14) gives general provisions on ships’ routeing.

What all do you know about ‘routeing charts’?

• Routeing charts are essential for use in passage planning for ocean voyages.
• They include routes and distances between major ports, ocean currents, ice limits, load lines and wind roses.
• Each charted area contains 12 separate charts for each calendar month, covering meteorological and oceanographic conditions that change throughout the year.
• It provides information such as wind roses showing wind speed and direction, the frequency and intensity of storms and low pressure, sea and air temperatures, air pressure and ice limits based on data averages.
• Following are the routeing charts available:

North Pacific Ocean
South Pacific Ocean
North Atlantic Ocean
South Atlantic Ocean
Indian Ocean
Gulf of Mexico and Caribbean Sea
Mediterranean and Black Seas
Arabian and Red Seas
Bay of Bengal
South China Sea
East China Sea
Malacca Strait to Marshall Islands

What specific standing orders will you give to your duty officers with regards to based on Rule 8 and 17?

Based on Rule 8, I will ask them to take early action to avoid any risk of collision or close quarter situation. Action taken must be positive, made in ample time, with due regards to observance of good seamanship. Alterations must be large enough to be readily apparent. Action taken must be monitored so as to pass at a safe distance and it must be ensured that CPA of 2NM with TCPA of 20 mins must be maintained with all vessels. When this cannot be achieved for whatsoever reasons, they must call me immediately without wasting any time. I will tell them that they have the engines and steering at their full disposal at all times.

Based on Rule 17, I will ask them to carefully monitor all the actions and movements of a give way vessel and not be complacent just because we are stand on vessel. I will tell them to take appropriate action to avoid collision as soon as it becomes apparent that the give way vessel is not taking any action or her action is not sufficient. I will tell them to call me in case of any doubt and if there is any confusion with regards to action to be taken in this case. I will ask them to avoid use of VHF for collision avoidance.

• I will firstly ensure safe and avoid getting my vessel in a close quarter situation with other vessels.
• Since I will be in a traffic congested area such as Singapore straits I will proceed at safe speed with my engines ready to stop or slow down when required.
• If collision is imminent, I will initiate the crash stop maneuver and try to take the impact on the bow which is strengthened.
• To avoid collision, I will not hesitate to let go my anchor and if the bottom of the seabed is soft mud or sand, I can also consider running aground if that makes my ship suffer lesser damage than collision. It can be decided on a case-by-case basis based on professional judgment.

What precautions will you take when entering a TSS?

• I will call a Bridge team meeting in advance to discuss the passage.
• Vessel will be on hand steering and manning as per Company‟s policy.
• I will have engines ready and proceed at a safe speed depending on the various factors such as traffic, sea room, weather conditions, visibility, etc.
• I will try out the engines and steering before entering the TSS.
• I will ensure compliance with Rule 10 of COLREGS and will enter a traffic lane at the termination of the lane, but when joining or leaving from either side I shall do so at as small an angle to the general direction of traffic flow as practicable.

• I will navigate with particular caution while entering the TSS as there may be vessels leaving the TSS and may alter the courses and cause a risk of collision.
• I will keep my anchors ready in case required for use in emergency situations.
• I will carry out reporting as required and comply with all the routeing measures as adopted.

Can a master navigate without pilot in mandatory pilotage waters if he’s confident?

Mandatory pilotage waters means a licensed pilot is a must and it will be an offense to navigate without a pilot in such waters.
The pilot is of great use when it comes to safely navigating ship in congested waters, co- ordinating with the VTS and has in depth knowledge regarding the local conditions which a Master may not have.
Even if the port allows and even if the Master is confident, it is always prudent to make use of the pilot service as it will enhance the safety of .

Pilot on board is doing wrong maneuvers and you are not happy with his decisions. What will you do?

I will express my dissatisfaction to the pilot at the very first instance. If he does not change his ways, I will immediately take over the con of my ship and ask for the pilot to be replaced. This will most certainly cause delays to my ship but nothing is more important than the safety of the vessel. I will make relevant entries in the ship‟s log book.
At all times, I remain in command of my vessel and have the over-riding authority over anyone for the safety of my ship as per ISM Code 5.2.

Pilot tells you that he would like to disembark 2 NM before the pilot station and it is clear ahead. What will you do?

• I will ask him for the reasons for making such a request.
• I will quickly ascertain if it is safe to navigate in that area without a pilot.
• I will take a decision based on the weather condition and traffic in the situation.
• Usually such a request is made when the seas is a little choppy outside the breakwater making it difficult for the pilot to disembark from the ship. In such cases, I will consider such a request. But if there is any doubt with regards to safety of the vessel, I will not agree to such a request and ensure pilot disembarks at the pilot station as marked on the chart.

Is the pilot boarding point also the pilot disembarkation point?

Yes, in most cases it is since no other mark is available on the chart.

What will you do if a pilot refuses to do Master – Pilot exchange?

• I will tell him that the Master-pilot exchange is important for the safety of the ship.
• If he still refuses, I shall contact the pilot station and inform them of the situation and ask for a replacement pilot. I shall make relevant entries in the log book.
• In no case, I will hand over con to the pilot without full and proper documented master-pilot information exchange.
• If required, I will take the vessel back and out to a safe area and wait for the new pilot.

You arrive at Pilot station and the pilot has asked you to wait for one hour. What will you do?

I will turn around in any safe direction and steam at slow speed for 30 minutes and return back to the pilot station in the next 30 minutes. I shall maintain contact with the pilot station on VHF and confirm the pilot boarding time and carry out my maneuvers accordingly. I will make relevant entries in the ship‟s log book. I will inform the Engine room of the delay in pilot boarding.

Pilot asks you to change the members of the Bridge team. What will be your actions?

• I will ask for the reasons of such a request being made by the Pilot.
• If the pilot requires additional person on bridge, I shall call for an additional look out keeping rest hours of my crew in mind.
• If the pilot wants to reduce the number of Bridge members, I shall politely refuse if it is not in line with the Company SMS.
• If the pilot wants to replace any of the members, I shall politely refuse telling him that we are limited persons onboard and replacing a person at this time would mean disturbing other persons rest hours.

What all things will you check in a passage plan for ocean sailing? What is vertex and limiting factor in GC sailing?

• I will check the route plotted on the ECDIS.
• I will check the marking on the ECDIS, dangers highlighted, call master point, routeing measures, reporting requirements, etc.
• I will check the safety settings on the ECDIS.
• I will check the information in the passage plan form is duly filled up.
• I will ensure routeing charts, IMO ships routeing, Ocean passages for the world, ALRS and all other publications are used for the passage planning.
• I will check the meteorological warnings and weather forecast for the route.
• If GC track is used, I will decide the limiting latitude which should not be crossed.

Vertex in the great circle sailing is that point where the great circle reaches its maximum latitude. Each great circle has two vertices, one in each hemisphere & they are 1800 apart.
Limiting factor – if the latitude of the vertex is too high, we need to modify the course and limit the latitude to avoid ice, fog, extreme cold and bad weather which are associated with very high latitudes. In such a case, we decide on the maximum latitude of the passage and do a composite circle sailing.

How will you review passage plan as a master?

• I will check the hard copy of passage plan presented to me for signature.
• I will check each and every section and ensure the form is duly filled up.
• I will check the route plotted on ECDIS and the markings.
• I will check important details such as Call master point, no go areas, reporting requirements, fuel oil change over markings, special area markings, anchorage, contingency anchorage, pilot boarding ground, abort point, etc.
• I will ensure all charts and publications are available and up to date.
• I will cross check the UKC calculations and ensure UKC is in line with UKC policy for the entire voyage.
• I will fill up „Master‟s Review of passage plan‟ section myself and then sign the same.
• I will forward the plan to the Company if the SMS so requires.

What is the difference between light and normal light?

• Resolution MSC.253 (83) gives the performance standards for al lights and al light controller and associated fittings. These have to be complied with for a light to be used as light.
• Some of these requirements are:

Material of the light fitting and associated equipment must be robust, non-corroding and must ensure a long-term durability for the optical qualities.
A ship of 50m or more in length must have a masthead light, sidelights and a stern light duplicated or be fitted with duplicate lamps.
Sufficient number of spare lamps for lights should be carried onboard.
• The luminous intensity of lights including the practical cut offs must be as required by Annex I of COLREGS.
• The luminous range of the light must comply with Rule 22 of COLREGS.
• In contrast, above rules or requirements do not apply for a normal light. What will you write in Master’s night orders?
The master’s night orders are traditionally a set of instructions for overnight bridge officers to digest and act upon. These are written down by Master in the Masters night order book, for the watch keeping officers. It is to supplement the Master‟s standing orders and highlight any specific concerns or instructions the Master needs the Officers to follow.

I will write the following in the Master‟s night orders as applicable:

• Comply with my standing orders, COLREGS and Company SMS at all times.
• Call me miles before arriving a specific point or at a specific time, with sufficient time available to appraise the full al situation and to develop proper night vision before reaching the pilot station or taking the con.
• Call pilot station and pass on the ETA and inquire about the berthing prospects.
• Call crew at a reasonable time to prepare anchors, pilot boarding arrangements, flags, etc.
• Call duty engineer to give 1 hr notice as marked on chart to ensure that engines are on standby at a particular point well in advance for the engines to be tried out astern.
• Ensure that bridge arrival checklists are completed and required systems checked.
• Comply with any mandatory reporting as marked on the chart.
• Comply with VTS and monitor VHF channel.
• Call me immediately in case of any doubt without any hesitation.
• Monitor weather forecast and al warnings.
• Additionally at anchor, monitor cable bearing and tension regularly, monitor vessels position, weather and vessels in the vicinity, call me if you receive any berthing instructions, E/R manned and engines on 10 minutes notice, etc.

What is the difference between Malacca strait and English Channel?

The English Channel is a water body separating the northern part of France from the island of Great Britain. It is found in the Atlantic Ocean. The English Channel has been ranked as one of the busiest seaways in the world. No single state has full governance of this water body; however, the United Kingdom has more significant control over it.

Malacca strait is a narrow stretch of water, between the Malay Peninsula and the Indonesian island of Sumatra. As the main shipping channel between the Indian Ocean and the Pacific Ocean, it is one of the most important shipping lanes in the world. It is governed on the basis of regional cooperation between States of Indonesia, Singapore and Malaysia. Indonesia controls the majority of the sea lane while Singapore controls the smallest area of the strait.

Other differences are:
• English Channel is a special area for Annex I and Annex V while Malacca Strait is not.
• English Channel is also an emission control area under MARPOL Annex VI and requires use of Low Sulphur fuel oil, whereas Malacca strait doesn‟t.

Which ships can use the inshore traffic zone?

As per Rule 10(d) of COLREGS,
• A vessel of less than 20m length, a sailing vessel and a vessel engaged in fishing can use the inshore traffic zone.

• A vessel can use an inshore traffic zone when she cannot safely use the appropriate traffic lane within the adjacent traffic separation scheme.
• A vessel may use an inshore traffic zone when en route to or from a port, offshore installation or structure, pilot station or any other place situated within the inshore traffic zone, or to avoid immediate danger.

How will you handover con to the pilot?

• I will firstly welcome the Pilot and carry out the Master pilot information exchange.
• I will tell him the engine status, propeller configuration, maximum draft and pass on all other relevant information.
• I will offer the Pilot card and the Information exchange form to the Pilot and obtain his name and signature.
• After this, I will verbally handover the con to the Pilot knowing that the Command of the vessel and full responsibility of the safety of the ship still lies on my shoulders.

At what times is the Master to be called?

The OOW should notify the master, in accordance with standing orders or the night order book, when in any doubt as to what action to take in the interests of safety. As per SCTW Code “Section A-VIII/2 – Watchkeeping arrangements and principles to be observed”, the OOW should notify the master immediately under following conditions:

• If restricted visibility is encountered or expected.
• If traffic conditions or the movements of other ships are causing concern.
• If difficulties are experienced in maintaining course.
• On failure to sight land or a mark.
• If any al mark or land is sighted unexpectedly.
• If a change in soundings occurs causing concerns.
• In case of breakdown of the engines, steering gear, etc.
• In case of malfunction of essential al equipment or any major alarms.
• If radio equipment malfunctions
• In heavy weather, if in any doubt about the possibility of weather damage
• If ship meets any al hazard, such as ice, derelict or a wreck.
• On receiving any distress alert or message.
• If any vessel security concern arises.
• In case of any other emergency or if in case of any doubt

The OOW will continue to be responsible for the watch, despite the presence of the master on the bridge, until verbally informed specially that the master has assumed that responsibility, and this is mutually understood. The fact that the master has taken control on the bridge should be recorded in the log book.

In Pacific Ocean, you sight an iceberg for which no warning is issued. What will you do?

As per SOLAS Chapter V, Regulation 31 (Danger messages), on sighting a dangerous iceberg, I will communicate the information by all means available at my disposal to ships in the vicinity, and also to the competent authorities. I will transmit the danger message through VHF to warn the ships in the vicinity and send a safety message using MF/HF.

In accordance with Regulation 32 (Information required in danger messages), I will include the following in my danger message:

The kind of ice-berg observed.
The position the ice-berg was last observed.
The time and date (UTC) when it was last observed.

In Pacific Ocean, you receive a distress message. What will you do?

• As per SOLAS Chapter V, Regulation 33 (Distress situations: obligations and procedures), if I am in a position to be able to provide assistance, I will proceed with all speed to the assistance of the persons in distress, if possible informing them or the search and rescue service that my ship is doing so. I will do this regardless of the nationality or status of such persons or the circumstances in which they are found.
• lf I am unable or, in the special circumstances of the case, consider unreasonable or unnecessary to proceed to their assistance, I will enter in the logbook the reasons for failing to proceed to the assistance of the persons in distress and also inform the appropriate search and rescue service accordingly.
• I will make relevant entries of all communication in the GMDSS Log book.
• If proceeding to assist, I will wait for the coast station to acknowledge the alert, but if not acknowledged by the coast station then I will acknowledge the message and establish communication with the distressed craft and gather all relevant information.
• I will maintain a continuous listening watch on the R/T frequency and try to communicate to the RCC regarding the situation and the intention of the vessel.
• I will carry out the SAR under an OSC and under the guidance of a SAR Mission Co- ordinator as per the instructions given in IAMSAR Volume III.

Distance 360 NM, speed 15 knots, course 090(T), current 2 knot southerly. Find CTS.

CMG is 0900 and current is 1800.
To find CTS, we draw a figure as shown alongside. Since it is a right angled triangle ABC,
We need to find angle C which will be the CTS.
BC = 15‟ and AC=2‟.
Therefore, Cos C = AC/BC = 2/15 Therefore, C = CTS = 820.

What is WOP? How to calculate wheel-over position using maneuvering characteristics?

WOP is the point on the initial course at which the wheel is put over to initiate the turning of the vessel.

The distance between the WOP and the point at which the ship commences its turn is denoted by „F‟ and depends on the size of the vessel, its loading condition, speed, trim and type of the vessel, etc. „F‟ distance is obtained from the manouevring characteristics of the vessel.

To calculate the WOP, we first decide the turning radius R and draw the curved track (arc AC). Now, we calculate the distance between WP (B) and the WOP using the formula:

F sin ϴ + R (1-cosϴ)

Where „ϴ‟ is the difference
between the initial & final course.

What is wheel over line? State the formulae for the same.

• If we have cross track error on the initial course, we can continue and commence alteration on reaching the wheel over line. It is a line parallel to the final course, which cuts the initial course at the WOP.
• The distance at which the Wheel over line is to be drawn parallel to the final course is given by the formula: Distance = F sin ϴ + R (1-cos ϴ)
(Where „F‟ is the distance between WOP & point when the vessel begins to turn, „R‟ is the radius of the turn and „ϴ‟ is the difference between the initial & final course)
• The value of F can be obtained from the ship‟s manouevering characteristics.

2nd Mate has called you on the Bridge due to heavy traffic situation. State your actions.

• I will go on the Bridge and quickly ascertain the situation visually and on the Radar.

• I will then take over the con and verbally tell it to the 2nd Mate who will later enter it in the log book.
• I will give the helmsman orders in compliance with COLREGS and take action to avoid any collisions or close quarter situations.
• If the traffic is causing concerns, I will give notice to E/R and have engines ready for immediate maneuver. If operating in UMS mode, I will have the engine room manned till the traffic condition improves.
• I will call additional look out if necessary.
• Once the situation is under control, I will ask the 2nd mate if he is confident to take the con. If yes, I will handle over the con to him and tell him to not hesitate to call me again in case of any doubt.

How will you know the exact time if all the time showing equipments fail?

I can use ITU-Radio Standard Frequency and Time Signal services referring to the ITU publications that are carried onboard or ALRS Volume 2 which gives details regarding radio time signals. For the area the vessel is in, I can tune in to the given frequency on MF/HF and know the time.

Describe ALRS and all the volumes.

Admiralty List of Radio Signals provides information on all aspects of Maritime Radio Communications, helping bridge crews to manage communications and comply with all reporting regulations throughout a voyage. It is split across six volumes. They are:

Volume 1 (NP281) – Maritime Radio Stations (Parts 1 & 2)
This includes radio details for Global Maritime Communications, Coastguard Communications, TeleMedical Assistance Service (TMAS), Radio Quarantine and Pollution reports, etc.

Volume 2 (NP282) – Radio Aids to , Differential GPS (DGPS), Legal Time, Radio Time Signals and Electronic Position Fixing System (Parts 1 & 2)
This includes List of VHF Radio Direction-Finding Stations, Radar Beacons, Aids to (AtoN), Radio beacons transmitting DGPS corrections, International Standard and Daylight Saving Times and Dates, International Radio Time Signal Broadcast details, etc.

Volume 3 (NP283) – Maritime Safety Information Services (Parts 1 & 2)
This volume includes Maritime Weather Services, Safety Information broadcasts, Worldwide NAVTEX and SafetyNET information, Submarine and Gunnery Warning details, radio-Facsimile Stations, frequencies and weather map areas.

Volume 4 (NP284) – Meteorological Observation Stations
This volume includes all Met Observation Stations listed worldwide.

Volume 5 (NP285) – Global Maritime Distress and Safety System (GMDSS)
This volume includes Worldwide communication requirements for distress, search and rescue, extracts from SOLAS and ITU Regulations, Distress and SAR contacts, Worldwide NAVTEX and Maritime Safety Information.

Volume 6 (NP286) – Pilot Services, VTS and Port Operations (Parts 1 – 8)
This volume includes detailed Pilot information with contact details, VTS information, contact details and procedures, National and International Ship Reporting Systems, Port information, contact details and procedures, etc.

Explain the Polaris calculation.

• From sextant altitude, obtain the True altitude by applying IE, Dip and Total correction.
• Obtain values of a0, a1 and a2 from the Pole Star Tables given in the Almanac.
• Sum of the True altitude, a0, a1 and a2 is then calculated.
• The sum is subtracted by 1 to get the observed latitude.
• Azimuth is then calculated and PL will be -/+ 90 of the azimuth. PL will be nearly E-W.

Why 1 is subtracted in POLARIS Calculation?

• For the ease of calculation of Polaris sight, the actual correction a0 is modified by adding a constant 58.8‟ to it. This is done in order to make all tabulated values in the almanac positive. The correction a0 is a function of LHA γ.
• The correction a1 is a correction for variation in a0 due to the observer‟s latitude being other than 500 which was used to calculate a0. A constant of 0.6‟ is added to make a1 always positive. The correction a1 is tabulated against LHA γ and observer‟s latitude.
• The correction a2 is for variation in values of SHA and declination of Polaris from the mean values assumed in calculation of a0. Again, 0.6‟ is added to make it always positive.
• Thus, (58.8+0.6+0.6 = 1) is subtracted from the final answer to get the Obs. Lat. Obs. Lat = T. Alt + a0 + a1 + a2 – 1

Explain Ex-meridian calculation and how to calculate the ex-meridian limits.

• Calculate True altitude by applying IE, Dip & Total correction to the sextant altitude.
• TZD = 900 – T.alt
• Cos MZD = Cost TZD + [(1-cos P). cos DR lat. Cos dec]
• P can be found by calculating the LHA.
• MZD +/- dec = Obs Lat (same name add, different name subtract)
• Calcuate Azimuth and PL which will pass through Obs lat and DR Long and be close to E-W.

The value of ex-meridian limits (EML) is obtained from the Nautical Tables such as Burtons or Norie‟s. The EML will be given in the table and can be obtained depending on the lat and dec. The EML so obtained will be in minutes of time. If the EML is found to be 15 minutes, it means that ex-meridian sight may be taken upto 15 mins on either side of the time of merpass. For example, if merpass time (SMT) is 1210 hrs, then Ex meridian sight can be taken anytime between 1155 to 1225 hrs.

A rough thumb rule can be used to obtain EML without using Tables. Calculate (Lat ~ Dec) same name subtract, opposite name add – square off the answer to the nearest whole number and use it as EML in minutes of time.

What are clearing bearings and clearing mark?

Clearing bearings are used for coastal , in order to have a quick visual reference of the ships position in relation to shoals, isolated dangers or wrecks. Clearing bearings are determined and prepared while passage planning and are marked on the chart. A prominent light house or fixed object is selected and a bearing is drawn from the reference point to keep clear of the dangers. The bearings are marked as NLT degrees (not less than) or NMT
degrees (not more than). It means that when vessel is on the particular course leg, she is safe as long as the TRUE bearing of the light house is not less than or not more than the stated value.

In the figure alongside, the vessel is safe from the shallow patches and other dangers as long as the true bearing of the light A is not less than 265(T) and as long as the true bearing of light B is not more than 275(T).

Clearing Mark:

When no prominent light house or fixed objects are available near a danger to mark the clearing bearing, a clearing line can be drawn using a clearing mark. The vessel is clear of the danger as long as the mark and danger are „open‟ and the danger is kept to the left or right of the mark.

In the figure alongside, the vessel approaching from the left-side of the image, will be on a safe course as long as the island remains „open‟ and to the left of the buoy (clearing mark).

Clearing line and clearing mark are used to clear a danger. It tells the navigator if the vessel is on the safe side or on the wrong side.

Name all the publications that are available on the Bridge.

SOLAS, MARPOL, COLREGS
LSA Code, FSS Code, ISM Code, STCW Code, IS Code & IBC Code
International Convention on Load Lines, 1966
International Convention on Tonnage Measurement of ships, 1969
Manual of Oil Pollution & Manual on chemical pollution
IMDG Code and Supplement
IAMSAR Volumes
International Code of Signals
Ballast water management convention and guidelines for its implementation.
Guide to Maritime security and ISPS Code
GMDSS Handbook
Ship‟s routeing
Bridge Procedures Guide
Bridge Team Management
Ship squat and interaction
Norie‟s Nautical Table, Distance tables, Sight reduction tables
Tidal stream atlases, ALRS, IALA Buoyage system
Ocean Passages of the World, List of Lights,
Nautical Almanac, Star Finder
Admiralty Guide to ENC symbols used in ECDIS (NP 5012)
Guide to Port Entry
International Medical Guide for Ships
The Ship Captains Medical Guide
Guide to Helicopter/Ship operation
Procedures for Port State Control
Peril at sea and salvage
The Mariner’s Guide to Marine Insurance
The Mariner’s Role in Collecting Evidence
ISGOTT
STS Transfer Guide
Tanker Safety Guide
Mooring equipment guidelines, Effective mooring, Anchoring systems and procedures
COSWP
CFR 33, CFR 46
CHRIS (Chemical Hazard Response Information System) Code
ITU Manual, ITU Radio regulations, ITU list of coast stations.
BMP 5
Plans and Procedures for Recovery of Persons from Water
IG System

Is there any publication available on the bridge to assist master in carrying out investigation?

• CIC Code
• The Mariner’s Role in Collecting Evidence
• P&I Club Hand Book

How will you monitor your position in coastal waters?

• Radar Ranges and Bearings
• Visual Compass Bearings
• GPS position and other EPFS
• Transit Bearing
• Parallel indexing on Radar
• ECDIS and radar overlays.

What are precautionary areas? Are vessels navigating in precautionary areas exempted from certain rules?

Precautionary areas: It is a routeing measure comprising of an area within defined limits where ships must navigate with particular caution and within which the direction of traffic flow may be recommended.

Vessels navigating in or near precautionary areas are not exempted from any rules and must continue to comply with all the Rules exercising particular caution when navigating in that area.

What is a hydrographic note?

• Hydrographic Notes allow you to inform UKHO of any ally significant information. This information could include new or suspected dangers, changes to al aids, amendments to details included in publications and suspicious charts or publications that could be counterfeit.
• These can be sent in paper format or sent using the ADMIRALTY H-Note App. In case of emergency, same can be sent to UKHO via e-mail or telephone.
• The hydrographic note formats are given on UKHO website, in Notices to mariners and also in Mariners Handbook (NP100).
• It is advised to send chart images and photographs either with the hard copy or as attachments to the electronic copy to help UKHO.

Describe TRS in detail including avoiding action.

A Tropical Revolving Storm (TRS) is a small area of very low pressure, around which winds of gale force (force 8 or more) blow spirally inwards, anticlockwise in the NH and clockwise in the SH. They are intense depressions that develop in tropical latitudes. They are often the cause of very high winds and heavy seas.

Formation & Movement: TRS typically form over large bodies of relatively warm water. They derive their energy through the evaporation of water from the ocean surface, which ultimately recondenses into clouds and rain when moist air rises and cools to saturation. TRS originate in latitudes between 50 and 200 and travel between W and WNW in the NH and between W and WSW in the SH, at a speed of about 12 knots. Somewhere along their track, they curve away from the equator – curve to N and then re-curve to NE in the NH and curve to S and then re-curve to SE in the SH. The re-curving is such that the storm travels around the oceanic high (300 N and S in the middle of the large oceans). After re-curving, the speed of travel increases to about 15 to 20 knots. At times, a TRS does not re-curve at all but continues on its original path, crosses the coast & dissipates quickly thereafter due to friction & lack of moisture.

Decay: TRS will decay –
• if it moves over land, thus depriving it of the warm water and moisture that it needs to power itself, and thereby quickly losing strength.
• if it moves over waters significantly below 26.5 °C.

AVOIDING ACTION:

Obtain the bearing of the storm centre: Face the wind, and according to Buys Ballot‟s Law, the storm centre will lie 8 to 12 points on your right in the NH and to your left in the SH. If the pressure has fallen 5 mb below normal, allow 12 points as it means that either the vessel is in the outer fringes of a well developed TRS or that the new TRS is forming in the vicinity. If the pressure has fallen 20 mb or more below normal, allow 8 points as it means that the vessel is near the eye of a well developed TRS.

Ascertain in which semi-circle the vessel lies: For a stationary observer, if the wind veers, vessel is in RHSC and if it backs, LHSC. This holds good for both NH and SH. For determining the semicircle, the vessel must be stationary and hove to. The wind observations should be compared with those 2 hours earlier. This is to give time for significant veering or backing and hence weed out any errors that may be caused by irregular gusts of wind. Veering and backing once detected should be continuous. If the wind veers at first and then backs, it means that vessel must have passed from one semicircle to the other. During the two hour interval between observations, while veering and backing of wind is being decided, the observer must be stationary. If not, conclusions arrived could be wrong and disastrous consequences may result.

Take avoiding action accordingly: Any avoiding action should aim to keep the vessel well out of the storm centre. If a vessel is in port when a storm warning is received, it may be advisable to proceed well out to sea so that vessel will have plenty sea room and sufficient depth of water to prevent vessel from pounding on the seabed. If proceeding out to sea is not possible, it would be advisable for the vessel to anchor outside the port, in whatever shelter she can find, drop both anchors with several shackles of cable out on each. The engines should be kept ready. Bursts of engine movement may be necessary to prevent dragging of anchors. Out in the open sea, following action is recommended:

A) If the vessel is in the dangerous quadrant: Proceed as fast as practicable with the wind 1 to 4 points on the stbd bow (port bow in SH) with 1 point for slow vessels with speed 12 knots or less and 4 points for fast vessels with speed more than 12 knots. The course should be altered as the wind veers (backs in the SH). This action should be kept up until the pressure rises back to normal i.e. the vessel is outside the outer storm area. If there is insufficient sea room, the vessel should heave to with the wind on the stbd bow (port bow in SH) until the storm passes over

B) If the vessel is in the path of the storm or if in the navigable semicircle: Proceed as fast as practicable with the wind about 4 points on the stbd quarter (port quarter in SH). The course should be altered as the wind backs (veers in the SH). This action should be kept up until the pressure rises back to normal i.e. until vessel is outside the outer storm areas.

How will you know you are approaching a TRS?

Following are the warning signs of approaching TRS:

Swell: The violent winds of the eye-wall send swell out in a radial direction. Swell can be experienced as much as a thousand miles away. Swell travels much faster than the speed of travel of the storm and approaches from the direction of the storm centre. It is usually the first indication of an approaching TRS.
Atmospheric pressure: The atmospheric pressure will fall steadily. The approach of a TRS should be suspected if the ship is in an area where TRS is common or if it is the time of the year when TRS generally occurs and corrected barometric pressure is 3mb below normal (taking account of diurnal variation). The presence of TRS is confirmed if the above conditions are met and the fall of barometric pressure is more than 5 mb below normal. A pressure drop of 20 mb is sufficient to cause a well developed TRS.
Appearance of the sky: Cirrus clouds in bands or filaments can be seen aligned towards the direction of the storm centre. Sometimes peculiar dark red/ copper colour of sky is seen at sunset before a TRS. Threatening appearance of dense and heavy clouds on the horizon and frequent lightning may be seen.
Storm warnings: Weather reports based on satellite pictures and observations from other vessels may contain storm warnings which give position and pressure of the storm centre and probable direction of the movement of the storm. However, the satellite pictures are restricted to only a few per day and observations from ships may be totally absent. It may thus happen that a vessel which notices the warning sign of a TRS is the first and only one to do so and therefore must inform and warn others about it. She should first send out a safety message containing the storm warning and after that, increase the frequency of its weather reports.

What are the conditions necessary for the formation of TRS?

High relative humidity: (open sea) This is very important since most of the energy required by the TRS is received by latent heat that is given off when the water vapour is transformed into water.
High Temperature: (tropics) For the development of TRS, high temperature is needed. For this reason, it occurs only in the Tropical regions, which ensure high relative humidity and a good rate of evaporation of the sea water.
LP area surrounded by areas of HP: (daytime over large islands) – This ensures that the winds will blow from areas of HP to areas of LP inwards.
Convection currents: (daytime over large islands) – this will ensure that the air rises continuously so that adiabatic cooling results in condensation that liberates latent heat. This latent heat provides energy for the TRS
Fair amount of Coriolis force: (latitude more than 50 N or S) – this will ensure that the wind which is blowing inwards from HP to LP will get sufficiently deflected so as to blow spirally inwards.
Weak prevailing winds: This is important, because if the prevailing winds were strong, the air would not rise vertically. It will rather be carried off horizontally thereby not allowing a TRS to form.

What are the factors affecting the movement of TRS?

Factors affecting the movement of TRS:

Trade Winds: TRS are steered by Global winds. In the tropics, easterly winds called the trade winds steer the TRS from East to the west.
Coriolis Force: After a TRS crosses an ocean and reaches a continent, the trade winds weaken. This means that the Coriolis Effect has more of an impact on where the storm goes. In the Northern Hemisphere the Coriolis Effect can cause a tropical storm to curve northward. (southward in the SH)
Westerlies: When a TRS starts to move northward, it leaves the trade winds and moves into the westerlies. Because the westerlies move in the opposite direction from trade winds, the TRS can reverse direction and move east as it travels north. This is called re-curving of the TRS.

Explain the 1-2-3 rule to avoid TRS.

The “1-2-3 Rule” is a TRS avoidance strategy using the 34-knot wind radius information given in the weather reports (storm message) along with an allowance factor for forecast error. The error factor is estimated as 100 NM for 24-hour forecast, 200NM for 48-hour forecast and 300NM for 72-hour forecast. (With improved technologies used for forecasting, it can be taken as 60, 120, 180 NM as well).

To draw the danger sector, we must first plot the present storm centre position with 34- knot wind radius. Next, we plot the 24-hour forecast position of the storm centre, with largest 34-knot wind radii + 100 NM. Similarly we draw 48-hour and 72-hour forecasted

position and use largest 34-knot wind radii + 200/300 NM. Thereafter, joining the tangents to these circles we get the danger area as shown in the figure above. This danger area must be avoided as this is the storm‟s area of influence.

Graphical plotting must be done and amended as and when new reports are received. Monitor the movement of the storm center and ascertain the danger area and change the avoidance strategy accordingly to keep clear of this danger area.

What is the sector method in TRS?

This method of TRS avoidance is used to keep the vessel away from the TRS influence zone. Various sectors are drawn based on information of the storm movement obtained.

A to B is the movement of TRS in the last 6 hours. From point B, we draw two lines 40 degrees on either side to form a sector. The radius used is the predicted 24 hour distance travelled by storm centre + a safety margin. Once next weather report is received, we get Point C and we can draw the next sector. Similarly, other sectors can be plotted and vessel must be maneuvered to keep out of the sectors drawn as the storm centre is expected to move within the sector in the next 24 hours. This method holds good even when the storm is curving or re-curving as shown in the figure.

Why weather is rough in Bay of Biscay?
The Bay of Biscay lies along the western coast of France and the northern coast of Spain and is open to the Atlantic on the west. Weather is particularly rough in this area during the winters. Depressions are formed and enter the bay from the west very frequently. They eventually dry out and are born again in form of thunderstorms. They cause severe weather at sea and bring light yet constant rain to its shores.

What is buy-ballots law?

If a person stands with his back to the wind, the low pressure area will be to the left in the NH and to the right in the SH. In other words, face the true wind, and the low-pressure area will be on your right hand side in the NH, left in the SH.

Draw some symbols that you will see on a weather fax. Also, draw the symbols for TRS, hurricane symbol for NH and SH. How will you represent 120 knots wind?

What is synoptic chart? What is prognostic chart?
Synoptic charts: These are weather maps that summarize atmospheric conditions over a wide area at a given time. It is usually updated every 6 hours and is based on a surface analysis and information received from weather stations, satellites, aeroplanes, ships, etc. It shows isobaric patterns, cloud cover, wind, temperature, dew point, precipitation, etc.

Prognostic charts: These charts give the predicted situation at a specified future time, based on present indications as deduced by an expert on the subject, using his skill and knowledge. It contains the same information as the synoptic chart, but in this case, it is predicted information. It can be a 12-hour, 18-hour, 24-hour, 48-hour or 72-hour prognosis. It helps the seafarer to amend the passage plan according to the forecast and carry out weather routeing.

Draw and explain ‘Egg diagram’.

Canadian ice services uses codes and symbols to describe all ice forms, conditions, and concentrations as accepted by the World Meteorological Organization. The ice codes are depicted in oval form, known as the Egg Code.

The basic data concerning ice concentrations, stages of development, and floe sizes of ice are contained in a simple oval form. A maximum of three ice types are described within the oval which is divided into 4 parts. This oval, and the coding within it, are referred to as the “Egg Code”.

How will you calculate wind speed from isobars?

From the synoptic chart, measure the spacing between the isobars at the desired location using a divider. In the synoptic chart, you will find a „Geostrophic Wind Scale‟. The divider is then placed on this Geostrophic wind scale, one leg of the divider is placed on the margin indicating the present latitude and other leg is placed horizontally to the right on the curved lines that indicate the Geostrophic wind speed. If the other leg of the divider falls between two curves, interpolation must be carried out accordingly Because of the friction between the air and the earth‟s surface, the wind speed over land is taken as half of Geostrophic wind speed and over sea since friction is less, it is taken as 2/3rd of the Geostrophic wind speed. This holds good only for straight or gently curving isobars.

Differentiate between TLD and TRS.

Tropical Revolving Storm (TRS) Temperate Latitude Depression (TLD)
Diameter between 50 and 800 miles average usually less than 500 miles. 1000 to 2000 miles across.
Only one single air-mass involved Two different air masses involved.
Wind speeds are maximum at lower levels and decrease with height. Wind speeds increase with height.
Travel east to west before re-curving. Always travel west to east.
No appreciable change in air temperature when it passes over an observer. Drastic changes of air temperature as much as 200C owing to the different air masses in contact.
Forms in areas of constant wind (trade wind areas) Usually form in an area of different wind directions.
Energy obtained from latent heat given off
by enormous condensation. Energy obtained from lifting of warm air by
cold air.

What is Ekman Spiral?

The Ekman spiral (named after Swedish scientist Vagn Ekman) is a consequence of the Coriolis Effect. When surface water molecules move by the force of the wind, they, in turn, drag deeper layers of water molecules below them. Each layer of water molecules is moved by friction from the shallower layer, and each deeper layer moves more slowly than the layer above it, until the movement ceases at a depth of about 100 meters. Like the surface water, the deeper water is also deflected by the Coriolis effect – to the right in the NH and to the left in the SH. As a result, each successively deeper layer of water are affected more by the Coriolis Force and less by the wind and movement of water above. Hence, this creates a spiral effect. Because the deeper layers of water move more slowly than the shallower layers, they tend to “twist around” and flow in a different direction that the surface current.

What is significant wave height? What are the factors affecting it?

Wave height is the vertical difference between the wave trough & wave crest. Significant wave height (Hs) is defined as the average height of the highest one-third waves in a wave spectrum. This is measured because the larger waves are usually more significant than the smaller waves. The larger waves can cause problems for mariners. Since the Significant Wave Height (Seas) is an average of the largest waves, one should be aware that many individual waves will probably be higher. The highest individual wave in a wave field can be nearly two times higher than the significant wave height.

Factors affecting significant wave height:

• Wind speed – More the wind speed, more will be the wave height.
• Fetch (distance the wind blows over water with similar speed & direction)- more the fetch, more will be the wave height.
• Duration of time the wind blows consistently over the fetch – High wind speeds blowing for long periods of time over long stretches of water result in highest waves
• Depth of water – As waves enters shallow water their speed decreases, wavelength decreases and height increases.
• Direction and speed of tide- If the tide direction is against the wind, this will also increase wave height.

What are tides? What is semi diurnal, diurnal, spring and neap tide?

Tides are periodic rise and fall in the level of the sea. Tidal range is the difference between High Water (HW) and Low Water (LW). The tidal range is small for deeper waters and high in coastal waters. Tides are caused due to the combination of Earth‟s rotation, gravitation attraction of the Earth and the forces of attraction by the Moon and the Sun.

Spring Tide: At Full Moon and New Moon, the sun is in opposition and conjunction with the Moon. Tide raising forces act in the same line producing very high HW and very low LW and the range of tide is very large. These are called Spring Tide. It happens two times in a month during the New moon and Full moon.

Neap Tide: When the Moon is in quadrature, tide raising forces of the Sun and the Moon are opposite to each other producing not very high HW and not very low LW and thus, the range is small. These are called Neap Tides. They occur 7 days after spring tides.

Diurnal Tide: An area has a diurnal tidal cycle if it experiences one high and one low tide every lunar day.

Semi-diurnal Tide: An area has a semidiurnal tidal cycle if it experiences two high and two low tides of approximately equal size every lunar day.

What is yaw?

The rotation of the ship that occurs about the Z-axis that is vertically located is known as yawing. Yawing is, in general, less harmful than the other types of ship motions. It is

brought about by a wave couple that acts perpendicular to the length of the ship. In general, it is impossible to keep a straight course when there are waves present, and there is always a small amount of yaw action on the ship. However, with proper rudder corrections, it is possible to reduce the effects of yaw.

What is barometer correction and formula for the same?

For the sake of uniformity of climatic record and forecasting purposes, all barometric readings should be reduced to a common datum – sea level in latitude 450 with no error due to temperature. Therefore, all barometric readings should be corrected for height, latitude, temperature and index error, the combination of which is known as barometric correction. For an aneroid barometer, only height correction and index error are applicable.

Height correction: Atmospheric pressure decreases as height increases. The reading on the bridge will therefore be lower than the reading at sea level. Thus, we add a correction for height at the rate of 1 mb for every 10 metres above sea level.

Latitude Correction: Since the gravitational force at the poles is greater than at the equator, one cc of mercury therefore weighs more at the poles than at the equator. This means that the height of column of mercury at the poles would be less than that that at latitude 450 whereas the height of the column at the equator would be more than that at latitude 450. This means barometer readings in latitudes higher than 450 need a plus correction while those in latitudes lower than 450 need a minus correction. The rate of change is about 1 mb for every 120 of latitude.

Temperature Correction: If the temperature of the barometer is different from its standard temperature, the pressure indicated by the barometer has to be corrected at the approximate rate of 1 mb for 60 difference. The correction is added if the actual temperature is below the standard temperature and vice-versa.

Index Error: It is the difference between the actual atmospheric pressure and the barometric pressure corrected for height, latitude and temperature. It is added if the corrected barometric pressure is lesser than the actual and vice-versa.

What is ITCZ?

The Inter Tropical Convergence Zone, or ITCZ, is a belt of low pressure that circles the Earth, near the equator, where the trade winds of the Northern and Southern Hemispheres come together. The intense sun and warm water of the equator heats the air in the ITCZ, raising its humidity and making it buoyant. Aided by the convergence of the trade winds, the buoyant air rises. As the air rises it expands and cools, releasing the accumulated moisture in a series of thunderstorms. It is most active over continental land masses by day and relatively less active over the oceans.

Name the various ocean currents with locations.

• North Atlantic Current
a) The North Equatorial Current
b) The Gulf Stream
c) The North Atlantic Current
d) The Canary Current

• South Atlantic Current
a) The South Equatorial Current
b) Brazil Current
c) The Southern Ocean Current
d) The Benguela Current

• North Pacific Ocean Current
a) The North Equatorial Current
b) The Kuro Shio
c) The North Pacific Current
d) The California Current

• South Pacific Ocean Current
a) The South Equatorial Current
b) East Australian Coast Current
c) Southern Ocean Current
d) Peru Current

• North Indian Ocean Currents (variable / seasonal)

• South Indian Ocean Currents
a) Equatorial Current
b) Mozambique Current
c) Agulhas Current
d) West Australian Current

• Currents in the Mediterranean Sea & Black Sea

Explain the working principle of AIS.

• The heart of the system is a transmission protocol called “Self-Organizing Time Division Multiple Access” (SOTDMA). This protocol is what allows AIS to be autonomous and continuously operational. It uses the precise timing of the GPS signal to synchronize multiple data transmissions from many users on a single narrow band channel.
• Each ship transmits data and receives data from all ships within an area called the CELL of the ship. The size of the CELL depends on the traffic density.

• In SOTDMA, each minute of time is divided into 2250 time slots. Each slot is of 26.67 milliseconds and contains 256 bits of data. The rate of transmission is 9600 bits/second. Thus, between the A1 and A2 AIS frequencies, there are 4500 time slots.
• When a ship accesses the system it searches for and acquires an unoccupied time slot. It transmits its report and also indicates the next location and timeout for that location. The highly accurate time signals from GPS prevent over-lapping. Each station determines its own transmission time slot based on traffic history and knowledge of future actions by other stations.
• Each ship sends to and receives AIS messages from all other ships or AIS stations in VHF range. If the amount of AIS data begins to overload the system, weaker stations that lie further away are ignored.

What is pseudo AIS? How will you come to know if you detect a pseudo AIS buoy?

Pseudo AIS or Virtual AIS are Aids to (AtoN) with no physical structure. It exists only through AIS messages broadcast from another location. A few uses of virtual AIS could be to mark buoys that are moved seasonally, such as in sea ice, or where a marker needs to be placed quickly, such as to mark a newly identified isolated danger or wreck.

Pseudo AIS can be used on light houses, beacons, etc for positive identification. Pseudo AIS can also be used to generate target in case of SAR operations. Pseudo AIS can be displayed on the ECDIS and Radar having AIS interface. One has to be more careful regarding the accuracy of the information transmitted by these pseudo AIS.

For identification and clear distinction of pseudo AIS from actual targets, V-AIS is marked on the charts and the buoy or other symbol is circled in magenta.

Why AIS should not to be used in collision avoidance?

• AIS is not yet recommended as such to be collision avoidance aid. It may be used in conjunction with other recognized collision avoidance aids such as Radar and ARPA, etc. but is not meant as a replacement for the same.
• AIS is only as accurate as the information transmitted by the other vessel‟s AIS. User inputs like Heading, speed, ROT, etc may be in error, missing or not updated.
• Broadcast of inaccurate, improper or outdated data can lead to confusion and dangerous situations leading to collisions.
• Also, some vessels such as pleasure craft, fishing vessels, warships, etc. may not be fitted with AIS or vessels may have their AIS switched off under certain circumstances. Hence, it is not advised to rely on AIS for collision avoidance.

What is AtoN?

A marine Aid to (AtoN) is a device or system external to vessels that is designed and operated to enhance the safe and efficient of vessels.
AtoN‟s include lighthouses, buoys, fog signals, radar beacons, leading lights, etc.

What is your company’s AIS policy in HRA?

It is recommended to keep the AIS ON while in the HRA since it can be useful for the naval forces to track the ship. However, the Master may use his discretion and switch off the AIS. When navigating in HRA, it is recommended that the AIS is programmed to only transmit minimum standard information, namely the ship‟s name, IMO number, call sign, MMSI, LOA, beam, position, course, speed and al status. When armed guards are onboard, we enter the destination as „armed guards onboard‟.

Explain the principle of GPS position fixing.

GPS works on the principle of „Ranging‟. The GPS receiver calculates its position by comparing its own self-generated timing signals with timing signals sent by orbiting GPS satellites. The time taken by the satellite signal to reach the receiver multiplied by the speed of radio waves gives the range to the satellite. Three ranges from 3 satellites are used for 2-D fixing while 4 ranges from 4 satellites are used for a 3-D fix. Average Speed and direction is obtained from successive position fixes.

Consider Satellites 1, 2 and 3 and a GPS receiver on the Earth. Say Satellite 1 transmits
signal at time „T‟ and the GPS receiver picks up the signal at time „T1‟. Therefore, Range
(R) = C x (T-T1) where,
C=speed of radio waves (3 x 108)
(T-T1) = time taken for signal to reach receiver.
We are thus located on the surface of a sphere of radius P1, centered on satellite 1. Similarly, we can get P2 and P3 using the other two satellites. Knowing location of all 3 satellites in space, we get 3 ranges that intersect at P which is the FIX.

What is RAIM and WAAS?

RAIM stands for Receiver Autonomous Integrity Monitoring. It is a technology developed to assess the integrity of GPS signals in a GPS receiver. RAIM uses the redundant GPS signals to produce several GPS fixes and compares these with a statistical function to determine whether or not a fault can be associated with any of the signals. Several GPS- related systems also provide integrity signals separate from the GPS signals. For example, WAAS (wide area augmentation system) used in aircrafts.
The Wide Area Augmentation System (WAAS) is an air aid developed to augment (supplement) the GPS, with the goal of improving its accuracy, integrity, and availability. WAAS uses a network of ground-based reference stations to measure small variations in the GPS satellites’ signals. These measurements from the reference stations are routed to master station, which sends the correction messages to geostationary WAAS satellites. These satellites broadcast the correction messages back to Earth, where WAAS-enabled GPS receivers use the corrections while computing their positions to improve accuracy.

What is WGS-84?

Hundreds of geodetic datum are in use around the world. GPS positions are referenced to
„World Geodetic System 84‟ datum (WGS 84) commonly used on al charts. The Earth has a highly irregular and constantly changing surface. Models of the surface of the earth are used in , surveying and mapping. WGS 84 is based on a consistent set of constants and model parameters that describe the Earth’s size, shape, and gravity and geomagnetic fields. Referencing the geodetic coordinates to a wrong datum can result in positional inaccuracy of hundreds of metres.

What is DOP? (Dilution of precision)

Dilution of Precision (DOP) is a term used for expressing the mathematical quality of a solution. Examples of DOP are:

• Time DOP (TDOP) – error in positioning due to clock errors.
• Horizontal DOP (HDOP) – error in the horizontal plane or 2-Dfix (x, y axis or lat-long)
• Vertical DOP (VDOP) – error in the vertical plane (z axis or altitude)
• Geometric (GDOP) – error due to satellite geometry or positioning in the sky.
• Position DOP (PDOP) – error in a 3-D fix (x, y, z axis or lat, long, alt)

Out of all, the PDOP is of most value to a navigator. PDOP in the GPS has an optimum value of unity. If the figure is higher, the solution is diluted. The PDOP will approach unity when a solution is made with a satellite overhead and three other satellites evenly spaced at low elevation angles. Modern GPS receivers may be programmed to reject a position solution if the PDOP level is high.

The geometry of the satellite can also seriously affect the accuracy of a position fix. When pseudo ranges are measured from satellites that are close together in the sky, the result is an enlarged area of improbability resulting in a bad GDOP. Alternatively, if the satellites are well spaced, the improbability area would be smaller. Modern GPS receivers pick the optimum satellites from those available for position fixing.

What is DGPS?

• Differential GPS is used to enhance the accuracy of a normal GPS. In the DGPS system, a DGPS Reference station is situated at a fixed location and it downloads the GPS data from the satellites. A computer at the fixed location calculates the pseudo- range from the GPS satellites and then compares it with the known ranges for that precise geographic location. It then computes a range error figure which is then broadcast over the MF band to all mobile stations to improve positional accuracy.
• Corrections may be given either as position corrections (lat, long, altitude) or, as corrections in pseudo-ranges of each satellite.
• Specially equipped GPS receivers receive the error information and apply necessary corrections to their own fixes. These corrections are valid only within a specified area about the DGPS ground station. On-board receivers may be programmed to auto track DGPS stations, receive the corrections from them and apply the same to their own fixes.

What is GPS Jamming and spoofing? How will you come to know if your GPS is jammed and giving false position? What is GPS spamming?

GPS jamming: This involves producing a RF signal strong enough to drown out the transmissions from GPS satellites. The subject of a GPS jamming attack will be instantly aware that something is wrong, as the system will be unable to produce a geo-location result.

GPS spoofing: This involves deliberately mimicking the GPS signals i.e. broadcasting fake GPS signals, tricking the receiver to think it is somewhere it is not. GPS spoofing in its simplest form involves location information being sent to the GPS receiver which is clearly false (it might, for instance, tell a ship out at sea that it is currently located on land).

GPS spamming: It is spamming of the GPS receiver i.e. sending out multiple unwanted GPS signals (similar or dissimilar) that are difficult for the GPS receiver to process

Thumb Rule: Jamming just causes the receiver to die, spoofing causes the receiver to lie. How to Know?
• GPS position will not be available in case of jamming.

• GPS position will be wrong in case of spoofing. This can be identified by carefully monitoring the ship‟s position from time to time and comparing with other means of position fixing.
• Use of radar and its overlay on ECDIS, are by far the best methods to identify jamming and spoofing when land is visible on the radar.
• Observing significant difference between DR position (position arrived with Gyro Course steered and distance by speed log) and GNSS fix
• Observing and verifying by using an echo sounder to compare the depths when sailing in suitable depth areas.
• Equipments meeting the latest IMO specifications will raise an alarm in case of a detected error to inform the navigator that the position has been lost.

What is Doppler shift?

Doppler shift is the apparent shift in frequency produced by a moving source and/or observer i.e. relative motion of the frequency source and observer. If both are not moving
w.r.t. each other, no Doppler shift will take place. GPS and other global satellite systems use the Doppler shift of the received carrier frequencies to determine the velocity of a moving receiver. Doppler-derived velocity is far more accurate than that obtained by simply differencing two position estimates. Thus, instantaneous speed is obtained from the Doppler shift of the satellite carrier frequency. In other words, the Doppler shift in received GPS signal can be used to compute the relative speed of the receiver w.r.t. the satellite. Average speed / direction is computed by measuring the difference between two successive positions.

Explain ECDIS symbols for floating and fixed buoy. (Simplified and traditional)

A buoy is floating whereas a beacon is fixed. Buoys are floating about in the water but moored to the bottom. Beacons don‟t float around. Lighthouses, for example, are beacons. Beacons can also be anything that‟s stationary and fixed to the earth. They can also be poles and structures out in the water that could cause obstruction. Difference in the ECDIS symbols for fixed beacons and floating buoys is shown below:

What is ECDIS purging?

ECDIS Purging refers to removing (purging) of all ENC Permits and ENCs from other ENC services before installing AVCS. If the system is not purged redundant ENCs may remain in the system database (SENC) and be available for use, even if the previous license has expired. However unlicensed ENCs cannot be updated and the user may be unaware of this if inadvertently navigating on one. Purging involves removal of installed ENC charts and ENC permits at regular intervals so that only the valid ENC‟s and permits are left in the system.

What is AIO?

Admiralty Information Overlay (AIO) is a worldwide digital dataset that is designed to be displayed over ENCs in ECDIS and other chart display systems to provide additional information during passage planning. The AIO is refreshed every week, as part of the AVCS Weekly Update and is issued on disc and by download. The ENCs do not include temporary information, thus, the Overlay contains ADMIRALTY Temporary & Preliminary Notices to Mariners (T&P NMs) that are issued for paper charts. The AIO also draws attention to areas where differences between ENCs and paper charts may affect the passage plan.

Both ECDIS fail. State your actions. What are the guidelines on ECDIS failure?

Actions on complete ECDIS Failure:

• Inform E/R and put M/E on stand-by and reduce speed if required.
• Switch over to hand steering and consider increasing bridge manning.
• Refer to available paper charts (small scale mandatory paper charts) and plot
vessel‟s position and ascertain the al situation of the vessel.
• Carry out troubleshooting and contact the manufacturer‟s service engineers for
guidance.
• Contact Office for assistance with troubleshooting and carry out al risk assessment to decide next course of action.
• Request Office to send scanned charts covering vessel‟s current geographical area.
• Warn traffic in the vicinity by making a Securite announcement on VHF.
• Record time and position of the failure and all other events in the Log book.

(In case of a single unit failure, use the second system and start defect rectification. In the event of a power failure with both systems reverting to UPS supply, consider a controlled shut down of one system.)

As per the performance standards for ECDIS:

• ECDIS should be provided with means for carrying out on-board tests of major functions either automatically or manually. In case of a failure, the test should display information to indicate which module is at fault.
• ECDIS should provide a suitable alarm or indication of system malfunction.
• Adequate back-up arrangements should be provided to ensure safe in case of an ECDIS failure. Facilities enabling a safe take-over of the ECDIS functions should be provided in order to ensure that an ECDIS failure does not result in a critical situation. A back-up arrangement should be provided facilitating means for safe of the remaining part of the voyage in case of an ECDIS failure.

What is ECDIS approval certificate? What if it is expired?

ECDIS units on board ships must be type-approved. ECDIS type approval is a certification process that ECDIS equipment must undergo before it can be considered as complying with the IMO Performance standards as given in RESOLUTION A.817(19) and MSC.232(82). The process is carried out by flag Administration-accredited type-approval organizations or marine classification societies in accordance with the relevant test standards developed by the International Electrotechnical Commission (IEC) (e.g. IEC 61174 – Ed.4).

MSC.1/Circ.1221 on validity of type approval certification for marine products states that the purpose of type approval certificate scheme is to witness the manufacturing and testing processes and the manufacturing arrangements. Thereafter, a type approval certificate is issued to the manufacturer the validity of which should not be more than 5 years which may be subject to annual verification of the manufacturer‟s process. The validity of the Type Approval Certificate itself has no influence on the operational validity of a product accepted and installed onboard a ship and that a product manufactured during the period of validity of the relevant Type Approval Certificate need not be renewed or replaced due to expiration of such Type Approval Certificate. The manufacturers that are manufacturing the ECDIS equipments will apply for a renewal survey before the expiry of their Type Approval certificate and ensure it stays valid.

Resolution A.817(19) – For ECDIS installed before 1st Jan 2009. MSC.232(82) – For ECDIS installed on or after 1st Jan 2009.

What is the ECDIS carriage requirement? Is it exempted for any ship?

SOLAS V/19.2.10 defines the carriage requirement for ECDIS.
It is mandatory for the following type of ships engaged on international voyages: Passenger ships of 500 GT and upwards
Tankers of 3,000 GT and upwards

Cargo ships, other than tankers, of 10,000 GT and upwards
Cargo ships, other than tankers, of 3,000 GT and upwards but less than 10,000 GT only if constructed on or after 1st July 2014.

(“First survey” means the first annual survey, the first periodical survey or the first renewal survey whichever is due first)

Exemption:

• Administrations may exempt ships from the ECDIS carriage requirements when such ships will be taken permanently out of service within two years after the implementation date specified.
• Also, following ships do not require to carry ECDIS:
a) Coastal ships not engaged in International voyages
b) All passenger ships (new & existing) of less than 500 GT
c) All Tankers (new & existing) of less than 3000 GT
d) New cargo ships other than tankers of less than 3000 GT
e) Existing cargo ships (constructed before 1st July 2013) of less than 10000 GT

How is an ENC numbered?

ENC cells are named using a unique eight alpha numeric character. For example, CC P 12345, where,
CC is the Producer code of the hydrographic office described in S-62
P is the Number representing the al Purpose [Overview (1), General (2), Coastal (3), Approach (4), Harbour (5), Berthing (6)]
12345 is the individual cell name. Each ENC producer has his own policy on naming of individual cells.

What is RCDS mode in ECDIS? Can we use it?

RCDS is an acronym for Raster Chart Display System. ECDIS used in RCDS mode, uses scanned copies of paper charts, called raster charts, instead of ENCs. Raster charts or RNC‟s are issued by, or under the authority of, a national hydrographic office. They do not offer a comparable level of data as compared to vector charts.

RCDS mode does not offer the full functionality of ECDIS, although it‟s excellent to have as a back-up arrangement. As per IMO Resolution A.817(19) as amended, if ENC coverage is not available, ECDIS may be used in RCDS mode together with an appropriate portfolio of up-to-date paper charts. There should always be an indication that the ECDIS is operating in RCDS mode.

Company SMS usually will define the requirement of the company with regards to use of RNC‟s where ENC‟s are not available. A vessel is usually permitted to sail in RCDS mode if approved by their Flag for geographical areas where there are no ENCs available.

What is CATZOC, POSACC, SOUACC and read me text files with reference to ECDIS?

CATZOC stands for Categories of Zone of Confidence. It tells the user about how well a particular area has been surveyed and how reliable the charted information is. This includes the positional accuracy, depth accuracy, seafloor coverage, extent of survey, etc. When using any ENC, the CATZOC information must be checked to know if the
±source information is reliable or not, or if any additional measures need to be taken when navigating in that area. CATZOC are as follows (from high accuracy to low):

A1 = 6 stars (highest level of accuracy) A2 = 5 stars (lower accuracy than A1)
B = 4 stars (the full area search is not carried out)
C = 3 stars (Depth anomalies can be expected in this category) D = 2 stars (Worse than Category C)
U = „U‟ mark (means the area is „unassessed‟ or „unsurveyed‟

The ECDIS manual will also give a table showing the maximum error in depths expected for each of these categories. Positional Accuracy (POSACC) and Sounding Accuracy (SOUACC) may be used to indicate that a higher position or depth accuracy has been achieved than defined in the Table. For example, a survey where full seafloor coverage was not achieved could not be classified higher that ZOC B; however, if the position accuracy was, for instance, ± 15 metres (ZOC B = ±50m) the sub-attribute POSACC could be used to indicate this. It would mean that though ZOC is B, the position accuracy is better than ±50m.

Read Me Text File: README.TXT file contains the latest information available on the use of ENCs in ADMIRALTY services. This information may be ally significant and should be reviewed for changes when ECDIS is being updated. It contains important general information, HO‟s information, withdrawn cells & other miscellaneous information.

What are the pros and cons of ECDIS?

PROS
• Availability: quickly and easily available.
• Faster and easier passage planning
• Improvement in Accuracy (such as calculation of distances, ETA‟s, etc.)
• Fast & Easy Corrections including T&P‟s
• Continuous Monitoring of Ship Position.
• Anti-Grounding Alarms and Settings Various Interfaces
• User Determined Alarm Settings
• Enhances Search and Rescue Capability onboard.
• Cost Efficient
• Environmentally Friendly

CONS

• Over reliance
• Errors in inputs to ECDIS
• Wrong settings or not changing settings in changing situations
• Alarm deafness (too many alarms, acknowledging alarms without checking)
• System Lag
• Specialized training
• Information overload (too much information clutter)

What is IHO check data set? How do you verify the ECDIS performance with it? If not in accordance, what action will you take?

The IHO had issued the ECDIS Data Presentation and Performance Checks (Check data set), which included two fictitious ENC cells (located in a land area) intended to assist mariners to identify if their ECDIS was using the latest IHO S-52 Presentation Library, edition 3.4. The dataset also highlighted if there were any known ENC display anomalies present in the system. Mariners were asked to run a series of quick tests using the check datasets within their ECDIS to ascertain if they were experiencing display issues. If the system was found to be running an old IHO Presentation Library or had a more serious display anomaly Mariners were advised to contact their ECDIS manufacturer or an appropriate equipment maintenance company to obtain software patches and investigate further to resolve the issues. Results of the tests were to be sent to the IHO for analysis and for use in revising IHO standards.

To address the display anomalies and improve the ECDIS user experience the IHO issued S-52 Presentation Library edition 4.0 in 2014. With this, the IHO Check Data set is no longer required as it was specifically designed and developed for ECDIS using the S-52 Presentation Library edition 3.4 or earlier.

You have two ECDIS onboard. After joining, how will you know which one is primary?

In the Form E (Record of Equipment for Cargo Ship Safety), it will be mentioned „Nautical charts / ECDIS‟ and the „nautical charts‟ phrase would be struck off. This means that the primary mode of is the ECDIS and not paper chart.

Just below that, Back up arrangement for ECDIS would be stated as “ECDIS”. This means that the back up for the first ECDIS is the second ECDIS. However, any ECDIS can be used as Master station (primary) and can be interchanged by the user.

After joining, I will check the ECDIS. Usually on the top right corner, it is written „MASTER‟ or „SLAVE‟ depending on the ECDIS type. Also, it is a practice onboard to keep one station as „Master‟ and other station as „SLAVE‟ which can be easily known after joining.

How to make the necessary corrections in the ECDIS and how it is implemented on board? Who issues these corrections and how?

Correction in ECDIS:

• Different software such as Chart-co, E-navigator, etc. are available which serve a variety of purposes mainly ordering, installing & updating of charts. For correction of the charts, every week a request must be sent via email in order to receive the chart corrections. Once the corrections are received in email, the same must be applied on the ECDIS as well as on the software used for the upkeep of the ENC‟s.
• It must be ensured that all charts are displayed as „Up-to-date‟ both on the ENC list on the ECDIS and software used.
• Similar request is also sent for T&P corrections (AIO) which is received via email and applied is the same manner.
• The corrections must be saved as a back-up for use in case of installing new charts. In such a case, the new charts must be installed using the Base DVD‟s and the permits must be applied. The BASE DVD may be not of the present week. Thus, the corrections from the date of the Base DVD till the latest week must be applied using the back-up corrections saved.
• Similarly, AIO must be saved as a back-up too. Some countries do not issue T&P
notices for ENC‟s. For such countries, T&P must be manually plotted on the ENC‟s.

Issuing of the Corrections:

• ECDIS corrections are issued by AVCS i.e. Admiralty Vector Chart Services. AVCS brings together official ENC‟s national Hydrographic offices around the world. It includes ENC coverage produced by UKHO in co-operation with Foreign Governments to provide comprehensive worldwide coverage.
• The corrections are issued to the Users in form of weekly updates by e-mail, online or on DVD.

What are the limitations of ECDIS?

• Lack of global coverage. RNC‟s need to be used where ENC is not available.
• Needs power supply for continuous and uninterrupted usage.
• Since it is an electronic device, it can malfunction and stop working.
• It needs an expert technician to repair if something major goes wrong.
• It can be affected by virus or can slow down or lag due to corrupted data or too much over-load.
• It can provide anti-grounding features only as long as the safety settings are correctly selected.
• Needs specialized training based on the Type and Model.
• It can lead to over reliance and complacency.
• Navigators may tend to forget basic chart work practices due to continued use of ECDIS.

• ECDIS has information displayed in layers & some of these may be not displayed.
• Over scale and under scale issues. Most ECDIS allow 2x of zooming in and out from the compilation scale.

What are safety contour, safety depth, shallow contour and deep contour? What is the problem when you set high safety contour value?

Safety contour relates to the depth contours as set by the mariner. The safety contour on ENC may be the same as set by the mariner or the next higher contour if the selected contour is not present. An alarm is generated within a specified time or distance before the vessel would cross a safety contour.

Safety depth refers to the spot soundings that will be highlighted if lower than the safety depth selected. It has no alarm, but it highlights danger.

Shallow and deep contours are used for demarcation between the shallow and deeper waters when 4 shades are used for display. Shallow contour tells the ECDIS the depth below which it is definitive for the ship to run aground. It is normally set at vessel‟s draft or more. Shallow waters patch (i.e. from zero metres depth to shallow contour value set) is area not navigable at all. Deep contour is the depth above which it is safest for the vessel as it will be in deeper waters.

If high safety contour value is set, then the ECDIS would keep giving alarm even when the depth of water is safe for . Also, if the selected safety contour is not present, the ECDIS automatically selects the higher safety contour.

What are the limitations of ECDIS with regards to safety contour?

• The ECDIS automatically selects the higher contour than the selected safety contour when the selected safety contour is not available. For example, if safety contour selected by user is 11m, and available contours are 5, 10, 15, 20 and so on, the ECDIS automatically selects 15 as the safety contour. This means that the ECDIS will give alarm once the depth is below 15m even though depth range of 11m to 15m is safe for the vessel.
• Some of the ECDIS models when restarted go back to the default safety settings. The user needs to manually re-enter the safety settings.

Who is authorized to change the ECDIS settings onboard?

Safety settings of the ECDIS are part of every passage plan. Depending of the vessel‟s draft, UKC requirement, squat and various other factors, the safety contour is selected by the Master and discussed with all during the Bridge team meeting. The safety setting is then entered in the ECDIS by the navigating officer prior to departure of the vessel from

port. The safety settings may be the same or different for the passage and arrival port and this too will be mentioned in the passage plan approved by the master and discussed with all. The ECDIS is specially marked at points where the safety settings need to be changed. This is done under the Master‟s authority and the navigator can change the settings upon crossing such points and relevant entries must be made in the Log book.

What is the difference between head up, course up and north up mode of Radar?

In head up mode, the „up‟ direction of the display (PPI) represents the vessel‟s heading. It is an unstabilized display and if there is a change in the vessel‟s heading, the entire picture (besides the heading marker) will rotate by an equal amount but in the opposite direction. The land echoes get smeared across the screen during this period and obscure the small fixed targets or floating objects for some time till the vessel is steady on the new course. The bearings taken on the fixed scale are relative bearings. It is advantageous during berthing and coastal as it gives a good orientation when compared to the visual view outside the bridge windows.

In north up display, the „up‟ position of the PPI represents the true north and the heading marker represents the true course of the own ship. When the vessel alters course the compass stabilization signal is used to produce simultaneously a rotation of the heading marker in the same direction as the change of heading. As a result there is no rotation of picture on the screen. Only heading marker rotates to the new heading. The true north remains coincident with 000° on the fixed scale. The azimuth-stabilizing signal is from a gyro compass. North Up display is often preferred as the orientation of the radar picture will match that of a chart. The north-up stabilized display overcomes the disadvantages of head-up by removing the angular smearing of picture associated with any change in heading. It also allows reading off true bearings directly and quickly from the fixed bearing scale. This feature is of importance in as well as for collision avoidance.
The main disadvantage of this type of display is that while approaching a port if the observer views the radar screen & looks outside the wheel house window, he finds it difficult to compare the radar picture with the visual view, particularly when on any course other than northerly or anywhere near that.

In course up mode, the „up‟ direction of the display represents the direction which has been input as the vessel‟s desired course. In the course-up (stabilised display), the bearings are true bearings, if read-off on the outer azimuth ring and relative bearing, if read-off on the inner fixed bearing scale.

How will you use X-band and S-Band radar for ?

I will use the X band radar at a smaller range for collision avoidance and the S-Band radar at a longer range for long range scanning.

What is radar plotting? Explain the WOA triangle.

Radar plotting is the systematic plotting of the radar targets on a radar plotting sheet and calculating the target details such as course and speed, CPA and TCPA. It is basically doing the work of the ARPA manually.

For doing this, we draw a WOA triangle. In an WOA triangle, point O is the first observation (range and bearing) of a target and A is the second or the third observation of the same target. OA is drawn and extended and its perpendicular distance from the centre of the plotting sheet gives us the CPA. TCPA can be calculated using easy mathematics.
WO is vessel‟s course and speed for the time interval which is plotted from „O‟ backwards.
WA so achieved is the targets course and speed.

Which radar to be used when coasting and at what range?

Both radars must be used during coasting at different range scales. X band radar must be set on 3NM or 6NM depending on the traffic conditions whereas S-band radar must be set on 6NM or 12NM depending on the requirement of long range scanning. During berthing, the ranges have to be reduced to avoid cluttering of the display as well as to pick up small targets and land objects easily on the radar.

Using true vectors on your radar, how will you identify if ROC exists?

True vectors of the target and the own ship can be increased in length (time) and thus can be compared to see if target will collide with own vessel i.e. ROC exists or vessels will pass well clear.

What are the requirements of ROTI?

As per SOLAS V/19, all ships of 50,000 GT and upwards shall have a rate-of-turn indicator, or other means, to determine and display the rate of turn.

Resolution A.526(13) gives the performance standards for ROTI.

What are the requirements of LRIT?

• SOLAS V/19-1 gives the requirements of Long ranging information and tracking of ships. The requirements apply to the following ships engaged in international voyages:

Passenger ships including high-speed passenger ships.
Cargo ships including high-speed craft, of 300 GT and upwards
Mobile offshore drilling units
• Ships shall automatically transmit the following LRIT information:
the identity of the ship;
the position of the ship (latitude and longitude); and
the date and time of the position provided.

• Ships shall be fitted with a system to automatically transmit the above information.
• Ships, irrespective of the date of construction, fitted with AIS and operated exclusively within sea area A1, shall not be required to have the LRIT.
• Unless the national legislation of the Administration provides otherwise, ships entitled to fly its flag shall not incur any charges for transmitting LRIT information.
• The search and rescue services of Contracting Governments shall be entitled to receive, free of any charges, LRIT information in relation to the search and rescue of persons in distress at sea.
• Systems and equipment used to meet the requirements shall be capable of being switched off on board or be capable of ceasing the distribution of LRIT information.
• Revised performance standards and functional requirements for the LRIT are given in resolution MSC.263(84), as amended).

Explain in detail the working of LRIT.

• The LRIT system provides for global identification and tracking of ships utilizing the INMARSAT Satellite system. It is a system that requires vessels to automatically transmit their identity, position and date/time of the position at 6-hourly intervals.

• LRIT data is automatically transmitted every 6 hours through the following route:

Ship to Satellite
Satellite to CSP
CSP to ASP
ASP to LRIT Data Center.
The LRIT Data Center forwards this information to applicable parties via the International Data Exchange and after receiving feedback from DDP.

• Information transmitted by ships is available to the vessel‟s Flag State at all times. For another Flag State to access the information, they will send a request to the IDE.
• Linked to IDE is the Data Distribution Plan (DDP) that will have the „routing rules‟ and this will verify that the „requestor‟ can access the information. Each contracting government will provide these routing rules to the IMO, who has developed the DDP. The DDP ensures that LRIT data flows according to the wishes of a contracting government – i.e. providing information on vessels within 1,000 nautical miles, or 96 hours out from port. If the DPP verifies that the information request is valid, the IDE will then act as a link to the requesting data centre and the providing data centre.

What is CSP, ASP, LRIT Data Centre, DDP and IDE?

CSP (Communication Service Provider) – It provides the communication infrastructure and services to ensure end-to-end secure transfer of the LRIT message between the ship and the Application Service Provider (ASP).

ASP (Application Service Provider) – It converts the data to a common data format and sends it to the LRIT data centre.

LRIT Data Center – It stores and processes the data and determines which reports are to be sent to other coastal/port states via the International Data Exchange based on the data distribution plan. LRIT data centre could be national, regional or cooperative or international.

LRIT Data Distribution Plan (DDP) – It verifies that the Member State requesting information must be provided with the same or not. It specifies which are the parties authorized to receive LRIT data.

International LRIT Data Exchange (IDE) – It routes data to the authorized receiving parties.

Explain LUT, MCC, LRIT DC, MRCC and RCC and their locations in India?

A Local User Terminal (LUT) is a satellite receiving unit ground station that receives emergency beacon distress alerts relayed from the satellites. There are two-types of LUTs, the Low Earth Orbiting LUTs (LEOLUTs) & the Geostationary LUTs (GEOLUTs).

India has established two Local User Terminals (LUTs), one at Lucknow and the other at Bengaluru.

The Indian Mission Control Centre (INMCC) is a facility that manages space flights usually from the point of launch until landing or the end of the mission. It is located in Bengaluru and is responsible for coordinating with RCC‟s and other International mission Control Centres.

LRIT Data Center – It stores and processes the data and determines which reports are to be sent to other coastal/port states via the International Data Exchange based on the data distribution plan. The Indian National Data Centre for LRIT was set up & made operational at Directorate General of Shipping (DGS) Mumbai in July 2009.

MRCC stands for maritime rescue coordination centre. MRCC‟s in India are located at Mumbai, Chennai and Port Blair. There are 10 Maritime Rescue Sub Centres (MRSCs) and 03 Maritime Rescue Sub Sub Centres (MRSSCs) that operate under these MRCCs.
It is responsible for co-ordinating air-sea search and rescue and works under Indian Coast Guard.

A rescue co-ordination centre (RCC) is a primary search and rescue facility in a country that is staffed by supervisory personnel and equipped for co-ordinating and controlling search and rescue operations. RCCs are responsible for a geographic area, known as a “search and rescue region of responsibility” (SRR). SRRs are designated by the IMO and the International Civil Aviation Organization (ICAO). RCC‟s established in India are at Chennai, Delhi, Kolkata and Mumbai.

What are the limitations of LRIT?

• It is not a continuous monitoring system as information is transmitted once every 6 hrs.
• Data available only to parties entitled to the information as per the DDP & information must be purchased.
• Unknown and variable cost of LRIT data received by authorized users.
• LRIT information is limited to only vessels identity, position and date/time information.
• There is no display for LRIT.
• Introducing costs of additional communication equipment for the sole purpose of transmitting LRIT reports on ships sailing exclusively in the GMDSS A1 and A2 areas and not fitted with satellite communication terminals.

LRIT fails 3 days before arrival US Port. State your actions.

• Since the failure of LRIT is viewed as non compliance of statutory requirements, I will immediately inform about the failure to the Company who will in turn inform the ship owner. The ship owner will then apply for a dispensation from the DGS and arrange for necessary repairs.

• I will inform the Flag State without undue delay and make an entry in the record of al activities and incidents maintained as per SOLAS V/28, setting out the details of the circumstances.
• In consultation with the National DC, alternate reporting system can be established.
• I will also inform the US Local agent and ask him to inform all concerned parties in the port of arrival regarding the failure and the dispensation availed from the Flag State.
• I will also mention this in the eNOA along with any other defects or failures to be informed.
• I will coordinate with the Company to get the LRIT repaired and operational at the port of arrival.

(As per DGS, if the vessel‟s LRIT system does not report two consecutive positions, same is required to be reported to the NDC LRIT with reason of failure and its remedy within 18 hours)

Echo sounder malfunctions just before arrival in port. Pilot is waiting at the Pilot boarding ground. State your actions.

• Inform the Pilot station and Company.
• Anchor at the designated anchorage or contingency anchorage.
• Arrange for a technician to visit the ship at anchorage to repair the echo sounder.
• Carry out a risk assessment to proceed till anchorage.
• Reduce speed and proceed with caution in deeper waters.

What is the working principle of the gyro compass? What is latitude and settling error?

A gyro-compass is a non-magnetic compass that uses a fast spinning disc spinning about the spin axis to point in the direction of geographical North. It uses the properties of the Earth‟s gravitational force and Earth‟s rotation and combines it with the properties of a free gyroscope i.e. the gyroscopic inertia (rigidity in space) and gyroscopic precession in order to convert a gyroscope into a gyro compass i.e. it makes the spin axis seek north and if displaced from the meridian, return back to point to the true north.

Latitude Error or Damping Error or Settling Error:

The damping error is applicable for gyro compasses damped in tilt which will settle with a displacement from the meridian. The gyro compasses that are damped in azimuth are not subject to this error. The magnitude of the error will be determined by the design and construction of the individual compasses. Damping error is proportional to tan of latitude. Damping error will be easterly in the NH and westerly in the SH and nil at the equator. There are three methods in which this error can be corrected.

A table and/or graph is provided by the Manufacturer. This graph/table of damping error (E/W) against latitude (N/S) must be referred & damping error applied manually to all the courses steered and bearings taken.
An arrangement is provided by the Manufacturer such that the lubber line will turn as per the latitude set by the operator. The lubber line will turn clockwise for an easterly damping error (NH) and anticlockwise for a westerly damping error (SH).
A potentiometer knob is provided by the Manufacturer. Depending on the set latitude, the potentiometer provides electric signal to a correction torque motor which applies torque about the vertical axis which results in precession about the horizontal axis.

Gyro compass fails at berth. Vessel has to sail in an hour. What will you do?

• Inform Company, Local Agent and carry out trouble-shooting.
• Call a technician and get the Gyro compass repaired.
• Delay the pilot or request for the vessel to be safely moved to a lay berth or anchorage if possible using the Magnetic Compass.

What is Navtex? Explain its use and what frequency it works on.

Navtex is an international automated medium frequency direct-printing service for delivery of al and meteorological warnings and forecasts, as well as urgent maritime safety information (MSI) to ships. Navtex is a component of IMO/IHO Worldwide Warning Service (WWNWS). It is also a major element of GMDSS.

As per SOLAS Chapter IV/7, all ships shall be fitted with a receiver capable of receiving international NAVTEX service broadcasts if the ship is engaged on voyages in any area in which an international NAVTEX service is provided.

Onboard, a navtex receiver is fitted which is used to receive the al and meteorological warnings and forecasts and other MSI.

The international navtex frequency is 518 kHz and these broadcasts are always in English. National transmission where supported, uses 490 kHz specifically for broadcasts in local languages.

How will you check your bridge equipments in yard delivery?

• During the sea trials, make sure all equipments are working satisfactorily.
• Use all the possible functions and check that they are working correctly.
• Ensure that the User manuals are available and have a conformance certificate or a type approval certificate from Class or any other recognized organisation.

• Prepare your own checklist for each bridge equipment and ensure all are in good working condition and any defects or irregularities must be noted down.
• Ensure all bridge equipments are at a compass safe distance as indicated on the equipment itself.

State the requirements for BNWAS. Also, explain its working.

• As per SOLAS V/19, all ships of 150 GT and upwards and passenger ships irrespective of size.
• The BNWAS shall be in operation whenever the ship is underway at sea.
• BNWAS installed prior 1st July 2011, may be exempted from full compliance with the performance standards adopted by IMO at the discretion of the Administration.

Working of BNWAS:

• BNWAS working is based on a series of indications and alarms to alert first the OOW and, if he is not responding, then to alert the Master or another qualified officer. Additionally, the BNWAS may provide the OOW with a means of calling for immediate assistance if required.
• Once operational, the alarm system should remain dormant for a period of between 3 and 12 min. At the end of this dormant period, the alarm system should initiate a visual indication on the bridge. If not reset, the BNWAS should additionally sound a first stage audible alarm on the bridge 15 s after the visual indication is initiated.
• If not reset, the BNWAS should additionally sound a second stage remote audible alarm in the back-up officer‟s and/or Master‟s location 15 s after the first stage audible alarm is initiated.
• If not reset, the BNWAS should additionally sound a third stage remote audible alarm at the locations of further crew members capable of taking corrective actions 90 s after the second stage remote audible alarm is initiated.
• In vessels other than passenger vessels, the second or third stage remote audible alarms may sound in all the above locations at the same time. If the second stage audible alarm is sounded in this way, the third stage alarm may be omitted. In larger vessels, the delay between the second and third stage alarms may be set to a longer value on installation, up to a maximum of 3 min, to allow sufficient time for the back-up officer and/or Master to reach the bridge.

State the requirements for VDR. What all feeds are included in S-VDR and VDR?

SOLAS V/20 deals with the carriage requirements of VDR. It states the following:

To assist in casualty investigations, ships, when engaged on international voyages, shall be fitted with a voyage data recorder (VDR) as follows:

• Passenger ships irrespective of size and cargo ships of 3000 GT and upwards.

To assist in casualty investigations, cargo ships, when engaged on international voyages, shall be fitted with a VDR which may be a simplified voyage data recorder (S-VDR) as follows:

• Cargo ships of 3,000 GT and upwards constructed before 1st July 2002.
Administrations may exempt cargo ships from these requirements when such ships will be taken permanently out of service within two years after the implementation date specified.

Administrations may exempt ships, other than ro-ro passenger ships, constructed before 1st July 2002 from being fitted with a VDR where it can be demonstrated that interfacing a VDR with the existing equipment on the ship is unreasonable and impracticable.

DATA RECORDED BY VDR DATA RECORDED BY S-VDR
Date, Time and Position (GPS) Date, Time and Position (GPS)
Speed (Log) Speed (Log or GPS)
Heading (Gyro) Heading (Gyro)
Bridge and VHF Audio Bridge and VHF Audio
Radar Display Image Radar Display Image or only AIS Data
ECDIS Any other NMEA format data
AIS Data
Depth (Echo-Sounder)
Bridge Mandatory Alarms
Rudder Order & Response
Engine & Thruster Order & Response
Hull Opening Status, W/T & Fire Doors status
Acceleration & Hull Stresses, Rolling Motion
Wind Direction and Speed
Configuration Data
Electronic Log Book (if used)

Explain the VDR data extraction procedure.

The VDR data extraction procedure is maker-specific and will be clearly indicated in the User Manual of the equipment. In most cases, the VDR has an interface for downloading the stored data for playback on an external computer. The software programme for downloading the stored data will be provided. The data once downloaded can be played on an external computer which has the playback software installed. If not already installed, the playback software will be provided on a portable storage device such as a CD/DVD or USB, etc. The portable storage device containing the software along with the instructions will be stored within the main unit of the VDR.

Some VDR‟s are provided with Hard disks which must be taken out and replaced with a spare hard disk to ensure continued recording. The hard disk taken out can then be connected to a computer which has the playback software installed.

What are the requirements for annual testing of VDR?

As per SOLAS Chapter V/18, the VDR, including all sensors, shall be subjected to an annual performance test. The test shall be conducted by an approved testing or servicing facility to verify the accuracy, duration and recoverability of the recorded data. In addition, it should test the devices fitted to aid location. A copy of a the certificate of compliance issued by the testing facility, stating the date of compliance and the applicable performance standards, shall be retained on board the ship.

What is satellite compass?

Satellite compass is a device that uses GNSS to accurately calculate the vessel‟s heading. It can use GPS, Galileo, GLONASS, etc. It doesn‟t rely on the earth‟s magnetic field like the magnetic compass nor does it depend on the gyro compass that can be bulky and expensive to install. A satellite compass provides variety of data including GPS position, SOG, COG, ROT, etc. The satellite compasses are maintenance free and a great asset for any vessel.

What is dip in magnetic compass? Where are the magnetic poles? What is the difference between magnetic north and true north? Why is the magnetic north not constant?

Dip angle or magnetic dip is the angle made with the horizontal by the Earth‟s magnetic field lines. This angle varies at different points on the Earth‟s surface. In principle, it is the angle made by the needle of a vertically held compass.

Magnetic dip results from the tendency of a magnet to align itself with line of magnetic field. As the Earth‟s magnetic field lines are not parallel to the surface, the north end of a compass needle will point downward in the NH (positive dip) or upward in the SH (negative dip). The range of dip is from +90 degrees (at the north magnetic pole) to -90 degrees (at the south magnetic pole).

Magnetic poles are the two points on the Earth‟s surface at which the magnetic field points vertically downwards in the NH and upwards in the SH. In other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down in the NH and upwards in the SH.

True north is the direction that points directly towards the geographical North Pole. This is
a fixed point on the Earth‟s globe. The magnetic north is the direction that a compass needle points to as it aligns with the Earth‟s magnetic field. The magnetic poles are different from the geographical poles. MNP is not a fixed point but it moves due to the magnetic changes in the Earth‟s core. Since the Earth is not exactly symmetrical, the changes in the Earth‟s core in the NH and SH are not exactly similar. Hence, the MNP and MSP are not diametrically opposite to each other, like the geographical NP and SP which are points through which the Earth‟s rotational axis passes.

What are the requirements for magnetic compass adjustment? What is the validity of the adjustment certificate?

SOLAS does not specify any requirements for compass adjustment. The requirements are usually stated by the Flag State. For example, as per Merchant Shipping (Safety of ) Rules, 1997, Indian ships have to get the deviation table or curve checked for accuracy at least once a year or through record of compass deviations maintained. Where a ship has undergone substantial structural changes or alteration which are likely to affect such a deviation table or curve, or where large residual deviations are observed, the magnetic compass shall be readjusted and a new table or curve of residual deviation shall be made available.

As per SCTW Code Section A-VIII/2, compass‟ deviation should be determined at least once every watch while the vessel is at sea and, when possible, shortly after any major alteration of course. In addition, compasses should be inspected occasionally by a competent officer or compass adjuster.

The AMSA (Australian Maritime Safety Authority) has issued Marine Notice No. 19 of 2016 highlighting the importance of maintenance and adjustment of magnetic compasses. Salient points from the notice are mentioned below:

• Performance of the magnetic compass should be monitored and deviations should be recorded in a compass deviation book at regular intervals, ideally atleast once every watch and also shortly after a large alteration of course.
• If the observations for a magnetic compass on a vessel show a deviation of more than 5 degrees on any heading, the compass must be adjusted by a qualified compass adjuster or the master of the vessel to correct the deviation.
• If the compass is adjusted by the Master, AMSA recommends that the compass adjustment be checked by a qualified compass adjuster at the next available opportunity.

The rules for testing and certification of magnetic compasses are contained in ISO 25862:2009 which recommend that the compass should be adjusted when:

a) They are first installed.
b) They become unreliable.
c) Repairs or structural alterations have been made to the vessel that could affect the permanent or induced magnetism.

d) Electrical or magnetic equipment close to the compass is added, removed or altered.
e) They show any physical defects.
f) If a record of compass deviation has not been maintained or the recorded deviations are excessive.
g) Deemed necessary by the Master for the safety of and no less often that every two years, every dry docking or other significant structural work.

To ensure a compass is in good working condition, it is important to check performance of magnetic compasses particularly after:

a) Carrying cargoes which have magnetic properties
b) Using electromagnetic lifting appliances to load or discharge cargo
c) A vessel has been in a casualty where it has been subject to severe contact or electrical charges
d) A vessel has been operating on short voyages for a long period of time then relocates, which results in a large change in magnetic latitude, or
e) A vessel has been laid up or has been lying idle.

Can you adjust a compass onboard? What is the procedure?

Yes, as a Master, I can adjust a compass onboard if the deviation is more than 5 degrees on any compass heading. However, at the next first available opportunity I must get the compass adjusted by a certified compass adjuster. A deviation card is prepared by the compass adjuster after adjustment.
Requirement for shore adjustment is as per the Flag State rules. Most flag states follow the ISO 25862:2019 standard which requires the compass to be adjusted by shore compass adjuster once every 2 years. However, the Flag may require the deviation card to be prepared every year. Hence, the Master may need to swing the vessel to prepare the deviation card once between two shore adjustments. During this, if the deviation is found to be excessive, compass adjustment may be required to be done by the Master himself. Usually, the Company arranges for a shore compass adjuster to remotely adjust the compass. They tell the Master what needs to be done in a detailed step-by-step procedure.

A suitable place in the open sea is chosen where weather is calm, traffic is absent, and the variation is known. The vessel is then swung and kept steady on the cardinal and intercardinal headings and the gyro headings are noted. From this, the deviation can be calculated. If the deviation is more than 5 degree on any of the heading, then the compass needs to be adjusted. For E-W headings, raise or lower the fore and aft magnets and for N-S headings, raise or lower the athwartship magnets. Raising and lowering must be done till the time the deviation is reduced to a minimum or acceptable value. Once this is done, the vessel is swung again to check the residual deviation to ensure all values are in limits. If not, the adjustment can be made again. After the adjustment, the deviation is prepared with the recorded values.

Following are the steps for adjustment followed by the compass adjuster:

• Come to a cardinal magnetic heading, e.g., east (090°). Move the fore-and-aft magnets to remove all deviation.
• Come to a south (180°) magnetic heading. Move the athwartship magnets, to remove all deviation.
• Come to a west (270°) magnetic heading. Correct half of any observed deviation by moving the fore and aft magnets.
• Come to a north (000°) magnetic heading. Correct half of any observed deviation by moving the athwartship magnets.
• Come to any intercardinal magnetic heading, e.g., northeast (045°). Correct any observed deviation by moving the spheres in or out.
• Come to the next intercardinal magnetic heading, e.g., southeast (135°). Correct half of any observed deviation by moving the spheres.
• Do the same for next 2 intercardinal headings.
• Secure all correctors before swinging for residual deviations.
• Swing for residual deviations on as many headings as desired, although the eight cardinal and intercardinal headings should be sufficient.
• Should there still be any large deviations, analyze the deviation curve to determine the necessary corrections and repeat above steps.
• Record deviations and the details of corrector positions on the deviation card to be posted near the compass.

How will you make a deviation card onboard? What information do you get from such a card?

To make a deviation card onboard, we need to swing the vessel around. This can be done at anchorage taking gyro and compass bearings of a fixed object or landmark of known true bearing. The bearings are taken when the vessel is heading at the cardinal and intercardinal headings by compass.

„Swinging the compass‟ can also be done at sea. Following is the procedure:

The vessel is made steady at all the cardinal and intercardinal headings and the gyro headings are noted.
Gyro error is already found and so we get True Heading from the gyro headings noted.
Applying variation to the True Headings, we get the magnetic heading. From the magnetic heading and compass heading, we get the deviation.
The deviation calculated for each of the 8 compass headings (others by interpolation) can be plotted on a graph to make the deviation card onboard.
For more accuracy, the vessel can be steadied at 16 points instead of 8.
Advantage of swinging the compass at anchor is that the vessel can take bearings of the fixed object every 5 degrees of the compass to have a more accurate deviation card.

The deviation card gives the compass deviation values for various compass headings in the form of a table and/or curve. Other information found on a deviation card are as follows:

Adjustments made to the corrector magnets and their final position after adjustments
Weather conditions during the swinging
Variation
Location of the ship
Make and model of the compass,
Adjuster‟s sign and stamp

What is integrated system?

• An Integrated Bridge System (IBS) is a combination of systems which are inter- connected to allow the centralized monitoring of sensor information and control of a number of operations such as passage execution, communications, machinery control, safety and security.
• There is no single standard IBS design for ships and nor is IBS mandatory. However, classification societies do offer optional class notations for IBS. The extent to which the IBS design allows certain bridge functions to be automated will depend upon the design of the bridge, the type of equipments fitted and the layout of that equipment on the bridge.
• IBS consists of management system, alarm system, conning display, etc. the management system provides the mechanism for passage planning, executing and monitoring and therefore provides a link between the charts, position fixing systems, the log, gyro and the auto-pilot.

Two days after sailing from Cape Town, on a voyage to New York, both the radars fail. State your actions.

• I will carry out trouble shooting with the ETO.
• I will immediately inform the Company of the situation and keep them updated.
• The Maker‟s or service team will try to solve the issue remotely, if the problem cannot be solved onboard, I will liaise with the Company and proceed to a Place of refuge where repairs can be carried out.
• The Company will arrange for dispensation to proceed to the Place of refuge without any working radar.
• I will carry out al risk assessment and increase bridge manning. I will keep extra lookouts and reduce speed to maneuvering RPM so that engines can be used anytime when required. I will give wider berth to all passing traffic.
• I will keep two OOW‟s on each watch if possible keeping the rest hours in mind.
• In the vicinity of other ships, I will make securite announcement to let the other vessels know about the non-operational radars.
• I will inform the Charterer‟s incase any deviation is involved.

As per which regulation is a sextant onboard?

Sextant is onboard as per Flag State regulations. For example, the Merchant Shipping (Safety of ) Rules, 1997 require all Indian ships to carry a sextant onboard. Also, the Company SMS may require a celestial observation to be made to compare with the vessel‟s position every month. In such cases, a sextant is a must for making a celestial observation.

How will you cancel false distress alert? What actions will you take onboard so that it does not happen again?

A distress signal carries the utmost priority over all other communication. Hence, it is very important to cancel it once the emergency has been dealt with or in case the distress signal was inadvertently sent.

As per IMO Resolution A. 814(19), I will take the following actions:

• If false distress signal was sent via VHF DSC, switch off and switch on the transmitter. Set equipment on Ch. 16 and made broadcast to all stations.

ALL STATIONS, ALL STATIONS, ALL STATIONS
THIS IS “SHIPS NAME”
CALLSIGN:
MMSI No. POSITION:
CANCEL MY DISTRESS ALERT OF DATE: TIME: UTC

• If false distress signal was sent via MF, switch off and switch on the transmitter. Set equipment to R/T Frequency of 2182 KHz, and made broadcast to all stations. (similar broadcast as above)
• For HF, same procedure as above, but alert must be cancelled on ALL frequency bands on which it was transmitted.

• If false distress signal was sent by Sat-C, notify the appropriate RCC to cancel the alert by sending a distress priority message via the same CES through which the false distress alert was sent.
TO: RCC ………
FM: MASTER, SHIP NAME NAME OF VESSEL: CALLSIGN:
SAT-C I.D.: (9digit)
POSITION: LAT 00 „00‟N LONG 000‟00‟E
CANCEL MY INMARSAT-C DISTRESS ALERT OF DATE: TIME: UTC MASTER.

• If for any reason an EPIRB is activated accidentally, the ship should contact the nearest coast station or an appropriate coast earth station or RCC and cancel the distress alert.

Precautions to be taken to avoid false distress alert:

• I will ensure that all GMDSS certificated personnel are well instructed about use of GMDSS equipments and are competent to operate them.
• I will carry out necessary training on use of GMDSS equipment for sending distress alert and how to avoid false distress alerts.
• I will ensure that GMDSS equipment testing is only undertaken by person incharge.
• I will ensure that GMDSS equipment testing or drills are never allowed to cause false distress alerts.
• I will ensure that EPIRB is not tampered with or accidentally activated.
• I will ensure that no jet of water is directed at the EPIRB during accommodation washing.

What are functional requirements of GMDSS?

Functional requirements of GMDSS are given in SOLAS Chapter IV Regulation 4.

Every ship, while at sea, shall be capable:

of transmitting ship-to-shore distress alerts by at least two separate and independent means, each using a different radio communication service.
of receiving shore-to-ship distress alerts.
of transmitting and receiving ship-to-ship distress alerts.
of transmitting and receiving SAR coordinating communications.
of transmitting and receiving on-scene communications.
of transmitting signals for locating
of transmitting and receiving maritime safety information
of transmitting and receiving general radio communications to and from shore-based radio systems
of transmitting and receiving bridge-to-bridge communications.

How will you ensure that 2nd Officer is maintaining GMDSS?

• I will check the GMDSS Log as required by SOLAS IV/17.
• I will randomly carry out tests and checks of the equipments to ensure they are in correct working condition.
• I will monitor the actions of the 2nd officer, if required, while he is carrying out the GMDSS daily tests, weekly tests, etc.
• I will ask the 2nd Officer to give training to other officers and crew.
• I will check the PMS records and the files of nav. area warnings and met. warnings.

Describe the daily, weekly, monthly and annual tests / checks carried out on GMDSS equipments.

Daily Test:

VHF Daily Self Test
MF/HF Daily Self Test
GMDSS battery on/off load test
Printers test (paper to also be checked and renewed if required)
Navtex Daily Self diagnostic test Weekly Test:
Ship to Shore Test Call by MF/HF (acknowledgment must be received)
Ship to Ship Test Call (if shore acknowledgment not received after repeated attempts)
Station to Station VHF DSC Test Monthly Test:
Sat-C Monthly PV Test & Diagnostic Test
EPRIB Monthly Test
SART Monthly Test
GMDSS Portable VHF Test
Navtex Monthly Test
GMDSS Battery Monthly Tests (done by ETO)
Visual checks for Antennae Annual Test:
GMDSS Battery capacity test (when the ship is not at sea) (SOLAS IV/13)
SART Annual test by shore technician
EPRIB Annual test by shore technician
Two way Portable VHF annual test by shore technician
Annual GMDSS Survey by shore maintenance company

What are the various GMDSS sea areas?

There are four GMDSS Sea areas as described in SOLAS Chapter IV:

Sea area A1: means an area within the radiotelephone coverage of at least one VHF coast station, in which continuous DSC alerting is available.
Sea area A2: means an area, excluding sea area A1, within the radiotelephone coverage of at least one MF coast station in which continuous DSC alerting is available.
Sea area A3: means an area, excluding sea areas A1 and 42, within the coverage of an lnmarsat geostationary satellite in which continuous alerting is available.
Sea area A4: means an area outside sea areas A1, A2 and A3.

What are the various entries that are done in the GMDSS Log book?

Following are the various entries done in GMDSS Log Book:

• Names of all officers that are GMDSS Certified
• Name of the Officer designated for distress communication
• Details of all distress alerts received by the vessel.
• Details of various communications related to Distress, Urgency or Safety.
• Details of all the follow-up communications, actions taken by the vessel, etc.
• Details of daily, weekly and monthly checks carried out.
• Breakdown or malfunctioning of the radio equipment
• Breakdown of communications with coast stations.
• Daily Noon position of the vessel.
• Entries at arrival / departure port when the GMDSS watches are ceased / resumed.
• Hard Copy of all print out from the various GMDSS equipments (can be filed separately)
• Particulars of equipments such as SART, EPIRB, portable VHF, batteries, etc.

Where to find out minimum GMDSS certified officers required for your ship?

SOLAS IV/16 states that every ship shall carry personnel qualified for distress and safety communication purposes to the satisfaction of the Administration. All of them must be holders of GMDSS license one of which shall be designated to have primary responsibility for radio communication during distress incidents.

The number of GMDSS certified officers required can be found in the Minimum Safe Manning document. For an Indian flag ship, two officers with Indian GMDSS license or a dedicated Radio officer is required.

Why do we use GMDSS in low power in port?

As per ISGOTT,

• The use of a tanker‟s radio equipment during cargo or ballast handling operations is potentially dangerous.
• During MF/HF transmissions, significant energy is radiated which can, at distances more than 500m, from the transmitting antennae, induce an electrical potential in unearthed „receivers‟ (derricks, rigging, mast stays etc) that is capable of producing an incendive spark.

• It is therefore recommended that transmissions are not be permitted during periods when there is likely to be a flammable gas in the region of the transmitting antennae. Main transmitting antennae should be earthed or isolated whilst the ship is alongside the berth. If required to be operated for servicing purpose, it must be discussed during ship shore safety meeting.
• Use of VHF is considered safe. However, it is recommended that the transmission power be set to low power (one watt or less) when used in port operations for similar reasons as above.

Apart from ISGOTT ship shore safety checklist, most Company SMS and terminals will also require you to have your MF/HF terminal earthed or isolated (switched off) and VHF and AIS on low power.

What are the PMS routines for GMDSS Batteries?

• Daily on-load off-load test of the batteries.
• Annual Capacity test of the battery when the ship is not at sea
• Checking electrolyte level and its specific gravity. (not for maintenance free batteries)
• Physical condition and storage of the batteries
• Checking of PPE for the battery room.

What types of batteries are used in GMDSS radios?

Lithium-ion rechargeable batteries are used in GMDSS radios which must always be kept charged. Lithium batteries (non-rechargeable) are kept sealed and used only in case of emergency. They have a shelf life of at least 2 years.

What are the requirments of GMDSS battery?

GMDSS battery requirements are given in SOLAS IV / 13.

• There shall be available at all times, while the ship is at sea, a supply of electrical energy sufficient to operate the radio installations and to charge any batteries used as part of a reserve source or sources of energy for the radio installations.
• The reserve source or sources of energy shall be independent of the propelling power of the ship and the ship’s electrical system.
• A reserve source of energy shall be provided on every ship, to supply radio installations, for the purpose of conducting distress and safety radiocommunications, in the event of failure of the ship’s main and emergency sources of electrical power.
• The reserve source or sources of energy shall be capable of simultaneously operating the VHF, MF/HF, Sat-C, GMDSS emergency lighting and any other radio communication equipment installed.

• The reserve souce of energy should be sufficient to supply power for

1 hour on ships provided with an emergency source of electrical power, if it supplies power to the radio installations.
6 hours on ships not provided with an emergency source of electrical power supplying to the radio installations.
• Where a reserve source of energy consists of a rechargeable accumulator battery or batteries, they shall be capable of being automatically recharged to minimum capacity requirements within 10 hours and the capacity of the battery or batteries shall be checked, at intervals not exceeding 12 months, when the ship is not at sea.

Types of GMDSS Batteries:

Nickel Cadmium (could be of the maintenance free type)
Lead Acid batteries (could be of the maintenance free type)

What kind of batteries are there for SART and EPIRB?

Both SART and EPIRB have lithium batteries.

Explain the details and requirements of SART.

• A search and rescue transponder (SART) is a self-contained, waterproof transponder intended for emergency use at sea for providing the location of the distressed craft.
• It operates on the 9GHz frequency band and generates a series of blips on the X-band radar it is interrogated by.
• It has to be activated manually and once activated, it responds to radar interrogation by transmitting a signal which generates 12 blips on the radar and turns into concentric circles as the range between the two reduces.
• The SART also has an audio-visual indication to indicate correct operation and to alert survivors to the fact that a radar has triggered the SART.
• It is battery operated with capacity sufficient for operating 96 hrs in stand-by condition and 8 hrs when being continuously interrogated.
• SART is made of fibre-reinforced plastic which can withstand and bear the prolonged exposure to sunlight and extreme weather conditions.
• It is capable of floating free of the survival craft and can be mounted easily.
• It is of the international orange colour
• The SART should operate correctly when interrogated at a distance of up to at least 5 NM by a radar with an antenna height of 15 m.

As per SOLAS Chapter III / Regulation 6, at least one SART shall be carried on each side of every passenger ship and of every cargo ship of 500 GT and upwards. For cargo ships of 300 GT and upwards but less than 500 GT, atleast one SART shall be carried. For ships having free fall lifeboats and carrying 2 SART‟s, one of it should be stowed in the free fall life boat and the other in the immediate vicinity of the bridge.

Is GMDSS walkie talkie intrinsically safe?

The GMDSS walkie talkies are not intrinsically safe and hence, must not be used in areas where flammable gases can be present. The same can also be confirmed by reading the Operator‟s Manual. A label must be posted near the charging stations stating that the portable radios are not to be used in hazardous areas.

What is EPRIB? How does it work?

Emergency Position Indicating Radio Beacon (EPIRB) is a device to alert search and rescue services (SAR) in case of an emergency out at sea. It transmits a signal on a specified band to locate a lifeboat, life raft, ship or people in distress. AN EPIRB is a SECONDARY means of DISTRESS alerting which is to say that it comes later in the hierarchy of alerting SAR authorities in case of distress.

Working of EPIRB:

• EPRIB operates on 406 MHz frequency which is the standard international frequency for signaling distress. The radio transmitter is synchronised with CORPAS-SARSAT polar orbiting satellite system and sometimes also with geostationary GOES weather satellites. The latter however gets location information only if EPIRB is fitted with integral GPS receiver.
• An EPIRB transmits signals to the satellite. The signal consists of an encrypted identification number (all in digital code) which holds information such as the ship‟s identification, the position, etc. For this, the EPIRB is registered and programmed.
• The Local User Terminal (LUT) (satellite receiving units or ground stations) calculates the position of the casualty and passes on the message to the MRCC
• The MRCC then takes up the responsibility for the SAR ops and oversees the execution of the rescue mission.

What are the various types of EPIRB? What is the range of INMARSAT E EPIRB?

COSPAS-SARSAT– EPIRBS under the COSPAS-SARSAT system work on the 406 MHz and 121.5 MHz band and are applicable for all sea areas.
INMARSAT E–This EPIRB worked on the 1.6 GHz band and recognized by the Inmarsat geostationary satellite system. These were applicable for sea areas A1, A2 and A3. These are obsolete and no longer in use.
VHF CH 70 – These EPIRB work on the 156.525 MHz band (VHF) and is applicable for sea area A1 only.

Inmarsat E EPIRB is obsolete and no longer in use. The EPIRB when used could work only in sea areas A1, A2 and A3 which has the coverage of Inmarsat satellite.

You get a call saying that your EPIRB is transmitting distress alert. After verifying, you find that your EPIRB is in OFF position, but it is transmitting. What are you going to do?

• I will remove the battery and insert it again.
• I will put EPIRB on test mode as per manufacturer‟s instruction and confirm its working.
• I will contact the Company and inform them of the situation.
• I will contact the manufacturer and inform them of the defect and call for a service technician at the next port.
• I will cancel if any distress message has been sent by contacting the nearest coast station or an appropriate coast earth station or RCC.

What is an EPIRB SBM test?

As per SOLAS IV/15, satellite EPIRB‟s shall be annually tested for all aspects of operational efficiency, including coding and registration. This test is to be carried out annually within 3 months before the expiry of Passenger ship safety certificate. For cargo ships, the test is to be carried out within 3 months of expiry of Cargo Ship Safety Radio certificate or 3 months before or after the anniversary date of such a certificate. The test may be conducted on board the ship or at an approved testing station.
Satellite EPRIB‟s shall be subject to maintenance at interval not exceeding five years, to be performed at an approved shore-based maintenance facility. This is the SBM test which cannot be done onboard and the EPIRB has to be taken to the approved shore testing station.
Shore based maintenance is a SOLAS requirement. As approved by the Administration, ships engaged in sea area A1 and A2 need any one of the following three and ships engaged in sea area A3 and A4 need at least two methods:

Duplication of equipment
Shore-based maintenance
At-sea electronic maintenance capability.
Most of the ships have the first two. The owner or manager enters into a contract with certified radio company for shore based maintenance of the GMDSS equipments A certificate is provided by such a Company and must be kept onboard to prove the compliance with SOLAS regulation. The certificate is valid for a year and must be renewed before expiry.

How will you test the EPIRB?
EPIRBs can be tested through its self-test function, which is an integral part of the device. The procedure is given on the body and in the Operator‟s manual. It consists of a test button which has to be pressed. Some small lights will start blinking which indicates the equipment is working correctly. Other checks include checking expiry dates of HRU and EPRIB Battery, mounting and physical condition and markings on the EPIRB.

Which flag will you hoist if you are manoeuvring with difficulty?

Flag D – Keep clear of me. I am manoeuvring with difficulty.

You are steering from emergency steering platform due to steering failure. Which flag will you hoist?

Flag D – Keep clear of me. I am manoeuvring with difficulty.

How many flags are there in International Code of signal?

Alphabet Flags – 26 Substitutes – 3 Answering Pennant – 1 Numeral Pennants – 10

Total Flags = 40

What is the use of answering pendent?

• It is used as a decimal point when used with numeral pennants.
• Answering pennant when hoisted at the dip (halfway) the receiving vessel indicates she has seen the hoist.
• Answering pennant when hoisted close up (top of mast), the receiving vessel indicates she understands the hoist
• The answering pennant is to be lowered to the dip as soon as the hoist is hauled down at the transmitting station and hoisted close up again as soon as the next hoist is understood.
• Transmitting station is to hoist the answering pennant singly after the last hoist of the signal to indicate that the signal is completed.

What are polar orbiting satellites and geostationary satellites?

Polar orbiting satellites are those satellites orbiting on a polar orbit i.e. the satellite passes above or nearly above both poles of the Earth on each revolution. They are used to provide imagery and atmospheric temperature and moisture data over the entire Earth. It is also used for earth-mapping, earth-observation and as weather satellites or for communication.

Geostationary satellites are in a geosynchronous orbit 22,000 miles above the equator and spin at the same rate of the Earth (hence, stationary with respect to Earth) and constantly focus on the same area. They provide visible and infrared images of Earth’s

surface and atmosphere for weather observation, oceanography, and atmospheric tracking. These satellites are also used as communication satellites and for weather- based applications.

2nd Mate calls you at 2 am and tells you of a quick flashing light right ahead. There is no buoy on the chart and he is confused. He is on the phone, what will be your actions?

• I will rush to the Bridge immediately and check the light characteristics visually.
• Quick flashing white light would indicate a North Cardinal mark.
• I will take the Con and alter course and pass North of the light.
• I will check on the radar to see if any target is painted.
• I will check if the chart is updated or any new al warning is received.
• I will send a Hydrographic Note to UKHO incase any corrections need to be made to the chart.

Your vessel is going to Barcelona from Rotterdam. Tell me about the location for the two places and how will you prepare your passage?

Rotterdam is a city in Netherlands and Barcelona is a city in Spain. For a passage from Rotterdam to Barcelona, we have to come south navigating in the North Sea and English Channel and then out in the North Atlantic Ocean, Then, we have to move easterly crossing the Gibraltar strait and proceed in the Mediterranean Sea towards Barcelona which is on the NE coast of Spain.

Special Consideration in Passage planning:

• Rough weather in North Sea / English Channel / Bay of Biscay / North Atlantic Ocean
• Heavy traffic in the English Channel and Gibraltar straits
• Reporting in the English Channel, Gibraltar straits, arrival and departure ports.
• Change-over of fuel (LSMGO to VLSFO and vice-versa)
• Special areas for Annex I and Annex V (Mediterranean Sea and North Sea)

What is the difference between Swing circle and drag circle?

Swinging circle is the circle in which the vessel is expected to swing when at anchor. The radius for drawing a swinging circle is calculated by adding the ship‟s length and the length of the cable from the hawse pipe to the anchor. The centre of the circle will be the point where the anchor is let go.

(Number of Shackles x 27.5 m + Length of the Ship in meters)

„Drag circle‟ is a circle drawn with a radius that is found by substituting the ship‟s length by the length between the bow and bridge in the above formula. Any bearings taken to check on the position of the ship should, if the anchor is holding, give a fix within the drag circle. If a fix falls outside the drag circle, then the anchor is dragging.

• I will ask him to continue keeping a sharp look out and proceed to the Bridge.
• I will check if any light is visible or if any target is painted on the radar.
• I will ask the lookout man and the 2nd Mate to continue a sharp lookout and keep the light in sight once observed and monitor the movement.
• If everything is under control, I will leave the bridge informing the 2nd mate to call me without hesitation if any doubt exists.

2nd Mate calls you at 1 am and tells that one white light is at 2 points on port bow. He has monitored it for an hour and there is no change. State your actions.

• I will come to the Bridge and check what light can be seen.
• I will check the radar settings and see if any target is painted.
• I will monitor the white light and take visual bearings.
• I will take the Con and alter the vessel‟s heading and monitor to see if there is any change in bearing. If not, it could be a star or a planet.
• If everything is under control, I will leave the bridge informing the 2nd mate to call me again without hesitation if any doubt exists.

What do you know of the requirements for ALDIS lamp?

IMO has adopted the performance standards for Day light signalling lamp. Following are some of the requirements:

By day, visibility of the signal must be atleast 2 NM and luminous intensity of 60000 cd.
It should be designed in such a way that the illuminant can be easily replaced also in the dark.
They should not be solely dependent upon the ship’s main or emergency sources of electrical energy.
They should be provided with a portable battery with a complete weight of not more than 7.5 kg and capable for atleast 2 hour operation.
Atleast three spare bulbs must be provided.