"Effect of Drift Force and unstable moment"
SAMMON - the IDEAL tool to identify manoeuvring capabilities of a ship - SAMMON - learning the EFFECTIVE way
How to get information for wind & current limits to be potentially encountered by thrusters – or current? - this will be described in this movie:
- Measure Drift speed, due to beam wind with no propulsion;
- Measure drift speed using full thrusters
- Estimate wind & current limits to be potentially encountered by thrusters – or current...
- Finally there is a simple formula as Rule of Thumb: the transverse drift speed is about 7-8% of wind speed!
Another very good explanatory video by Knud Benedict. Absolutely worth seeing.
Yaw Stability is an important element of Ships Manoeuvrability - both for course keeping and turning ability. This first video in a series explains the Basic Principles of stability in steady state equilibrium conditions and the forces / moments involved
Following a surf riding and broaching incident and subsequent collision by an experienced vessel operator, QinetiQ have been undertaking extensive investigations into the risk mitigation and safety management of pilotage operations. This presentation looks to discuss the risks presented during pilotage services, and provide a critical review of vessel design and service delivery approaches to understand the potential risk mitigations and management of pilot boat safety.
This video complements the earlier demonstration of wind effect on straight track and shows now wind effect on turning circles. It can be seen that during a turn under strong wind the ship reduces turning when it comes close to equilibrium on straight track - if the Wind-to-ship speed ratio is big enough then the ship even goes straight instead of turning. This is shown for three samples for Head, Stern wind and Beam wind. The turning can be increased if the ratio of Wind speed-to-ship...