Vessel Head to Wind with Headway Vessel making Headway through the water, and Heading directly into the Wind. W is now well forward of amidships, and in fact very close to P; the wind is exerting no turning moment, or sideways force, on the vessel.
Ahead Movement of the Propeller The effect of transverse thrust whilst making an ahead movement is arguably less worrying than that of an astern movement, perhaps because the result is less noticeable. (a) The helical discharge from the propeller creates a larger pressure on the
CATZOC on the ENC in simple terms refers to the Quality and Accuracy of survey data and the applicable error in chart datum that sometimes can greatly affect vessel’s UKC calculations. Zone of Confidence (ZOC) has 6 Categories named A1, A2, B, C, D
Speed Many casualties are proven to occur as a direct result of excessive speed. Its effect can be insidious and a Master may find that he cannot keep up with events, which are happening too quickly. Effective control of the ship is slowly but inexorably
Vessel Stopped If the tugs apply the same bollard pull of say 15 tonnes each, it is to a position 80m fore and aft of the pivot point. Thus two equal turning levers and moments of 80m x 15t (1200tm) are created resulting in even
Duties of the master in case of a collision In case of collision between two ships, it will be the duty of the master of each ship, without endangering his ship, crew and passengers, if any: • To render to the other ship, its master,
Crash Stop No type of main engine can be reversed immediately from full rpm ahead to full rpm astern because no engine can drive the propeller at full revolutions astern while the ship herself is moving ahead at considerable speed. The application of
The Officer of the Watch should bear in mind that the engines are at his disposal. He should not hesitate to use them in case of need. However, timely notice of engine movements should be given when possible. He should also keep prominently in mind
General Ice is an obstacle to any ship, even an icebreaker, and the inexperienced Navigation Officer is advised to develop a healthy respect for the latent power and strength of ice in all its forms. However, it is quite possible, and continues to be proven
AIR MASS When air remains over an area of the earth’s surface for several days, its physical properties are affected by those of the earth’s surface. If the surface is WARM & WET, the overlying air will become WARM & HUMID. Eg. Air over the