Ship Maneuverability and Evolution Capacity

Maneuverability of a ship can be defined as the percentage of efficiency that allows the vessel to maintain a course or vary its bow, with the purpose of achieving a certain position with respect to its environment.

Defining Government Capacity

It is the property that the ship must have so that it can change course in the shortest possible time and space.

Maneuvers for Recovery Capacity

The Kempf Maneuver

The Kempf maneuver consists of the following actions:

• When the yaw rate reaches a constant value, the rudder is placed at 20° to the opposite side.
• When the yaw rate reaches a value identical to the previous one in the direction of the turn, the rudder is changed to the opposite side again.

Among the most important factors in this maneuver are:

• Time between successive movements of the rudder.
• The overshoot angle, which measures how much the ship's direction exceeds 20°.
• Keeping the ship on a stable course; the rudder is placed at 20° to one side.

Evolution Capacity

The parameters of a variable nature related to the vessel are:

• The displacement
• The draft
• The seat (trim)
• Speed

Parameters of a variable nature related to the environment in which the ship is located are:

• The existence of currents
• Tides
• Wind
• Ice
• Sea and restricted waters

The Williamson Turn

1. Note the position of the ship.
2. Put the wheel hard over to the side of the casualty.
3. After the ship has altered course by about 60 degrees, put the wheel hard over to the other side.
4. When the vessel is 20 degrees short of the reciprocal course, ease the wheel.

The Anderson Turn

1. Stop the engines.
2. Put the rudder over toward the person.
3. When clear of the person, go all ahead full, still using full rudder.
4. After deviating from the original course by about 240 degrees (about two-thirds of a complete circle), back the engines 2/3 or full.
5. Stop the engines when the target point is 15 degrees off the bow. Ease the rudder and back the engines as required.