PORT SIDE BERTHING
When the ship is tied to the jetty from her port side, the ship is moved towards the berth at certain angle. The astern thrust thus generated is used to stop the ship’s motion and to turn the bow towards starboard, which will turn the ship’s astern to port side.
As soon as the ship is parallel to the berth, the ship can be carefully and slowly maneuvered to its drafted position by astern kick, which provides the transverse thrust. The actual operation will highly depend on the berth position and available space.
STARBOARD SIDE BERTHING
It is important to balance the forward speed of the ship against the astern power needed to stop the same. The greater the forward speed, the greater is the astern power required to stop the ship. This result into greater effect of the transverse thrust, which brings the ship’s bow close to the berth and throw the stern off.
Aim to approach the berth by keeping the ship parallel. The effect of transverse thrust will swing the bow towards the berth.
DO NOT DO FOLLOWING
Increase the Approach speed
Ship can hit the berth with her bow before stopping, or the large astern movement used to stop the ship and the resulting transverse thrust can cause the stern to hit the berth.
A head kick near the berth
If a sharp kick ahead is made close to the berth, the ship’s bow can strike the berth.
Ignore the lateral motion
When approaching port-side to the berth, the ship’s lateral motion is to the port. Insufficient awareness of lateral motion can cause a ship to land heavily against the berth.
Stop too far
If the ship is stopped with her bow at a distance from the berth, it will be difficult to position it close to the jetty. In such situation, move the ship laterally and swing the rudder to port for bringing the bow close to the jetty.
However, note that this will only cause her to move in a lateral direction, away from the berth as lateral motion is always at right angles to the direction of motion and away from the direction of turn. This will make the operation more complex and longer.
If berthing against a knuckle, it is important to land flat against the straight part of the quay, and not on the knuckle.
Read More: SAFE NAVIGATION TECHNIQUES