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otnmbrd

wrote in
oups.com:

Looks to me like the captain was trying to bring the ship around head-
to-wind and the thing has so much windage, she is very reluctant to
turn that way. And his bow thruster is out of the water half the time!

At the speeds he appears to be making, keeping the head to wind is not
always that easy, especially with the type of windage these ships have in
this type condition. For the most part the thruster would be useless for
reason you give plus, much above 3k efficiency drops off considerably.

I've been saying for years that the ABS was stupid to allow naval
architects to include active anti-rolling in their stability
calculations. When a ship has to slow down for weather, that's when
the anti-roll fins are least effective and when the ship needs the
most stability. Not to mention if the power plant goes dark.

Not sure of the requirements for GM regarding stabilizers. As you say,
for active fin systems their effectiveness greatly reduces with reduction
in speed (this may have improved over the years) and is a prime reason to
use both active and passive systems (flume tanks) for maximum effect.
BG Course.... in conditions like these....if the rolling dosen't getcha
the pitching will.

otn