Maneuvering

When the ship is moored or held broadside to the current the area exposed to the current is approximately equal to length x draft (L x T). When the ship is manoeuvring in tide the water surrounding the ship is ... [Download and Read document]

Wind force depends on: windage, wind velocity (wind pressure), angle between apparent wind and heading. Wind pressure is proportional to wind velocity squared. Centre of wind pressure depends on distribution of windage alongside the ship. Wind force Wind force ... [Download and Read document]

All control devices could be divided in two main categories: active and passive. Active control devices: are devices actively fed by external energy. Passive control devices: are devices absorbing energy from ship speed and propeller race. Application: effectiveness of active ... [Download and Read document]

Some rules for interaction 1.    Maintain a sensible speed. Excessive speed magnifies interaction. 2.    If possible recognize and anticipate interaction. It is much preferable to avoid sheer than to try steer of it. 3.    Interaction effects are greater in shallow ... [Download and Read document]

Normally ships cannot sail faster than about 75% of the critical speed (except high speed craft) Effect of shallow water on manoeuvring Shallow water affects considerably manoeuvring characteristics of ships - Turning circles become larger in shallow water -Course keeping ... [Download and Read document]

Twin-screw ships have generally excellent manoeuvring qualities at zero and low speed, especially in the case of twin rudders and propellers well spread (fig. 6-1a). Additional turning moment improving manoeuvring qualities is created by: -Difference of propeller thrust directions (for ... [Download and Read document]

The ship-tug interaction is a function of many factors and depends mainly on: Type of tug co-operating with a ship, where the main difference results from the location of tug’s propulsion and towing point. The choice is between conventional single ... [Download and Read document]

Acceleration is the period from the moment when order of starting the engine is given to the moment when nominal speed of the ship is reached. Inertia stopping is a manoeuvre of stopping of the ship sailing at nominal speed ... [Download and Read document]