Research on hydrodynamic interaction indicates that if the speed of the ship near a bank is too high, the rudder may be less able to cope with the forces induced and control will be lost. The Nautical Institute highlights this in its latest Mars Report, in which an LPG carrier hit a barge being towed by a tugboat as a result of hydrodynamic forces.
Manoeuvring large ships at close quarters and on shallow water is one of the most difficult aspects of shiphandling because of the complex hydraulic interactions depending on the ships' speeds, on the water depth and on lateral restrictions like in canals. Training is conducted both on meeting and on overtaking ships in shallow waters. This video shows how overtaking in a canal can easily fail.
More information: http://www.portrevel.com/3781-shiphan...
