"Effect of Drift Force and unstable moment"
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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
New guidance for PBAs with trapdoors. Released 4.11.2020 at NZMPA Conference in Dunedin, NZ. Distinct difference to suggestions in many other countries, is that we challenge operators who have the ladder suspended from the accommodation ladder (gangway) and not secured to the ship. SOLAS states that pilot ladder shall be secured to the ship, and securing strongpoints, shackles and ropes shall be as strong as the sideropes.
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...
This video provides the detailed explanation of the phenomenon showed in Part 1 of this topic and a solution for this problem at the end. This phenomenon was recently disocovered by Dr. Steve Shaojie Tang and published in his book by Faiteve inc in 2018. The book info can be found at Faiteve inc https://www.faiteve.com/ The testimony of the captain on duty in the public hearing of Golden Ray capsizing at https://livestream.com/uscginvestigations/events/9252896/videos/211109207 in the time...
When the world locked down, Australia’s marine pilots continued bringing ships safely into the nation’s ports to deliver the goods we depend on. Around 6,000 ships visit the ports of NSW each year and meeting them at sea to help them navigate into our ports and harbours are Port Authority’s marine pilots and cutter vessel crews. ••• Port Authority of New South Wales manages the navigation, security and operational safety needs of commercial shipping in Sydney Harbour, Port Botany,...