GHS FAQ

Question QA002 :
Can a geometry model be rotated through different angles of yaw and saved in a geometry file (similar to the "shift" command)?
Can Cross Curves of Stability be calculated for pitch?
Can the wind heeling moment be applied in different directions ?

Answer :
There is no command to rotate the ship geometry similar to the "shift" command. However, you can define the axis for heeling to be at any angle. See the AXIS command in the main program.
When the axis is rotated to 90 degrees, "heel" becomes fore-and-aft inclination. Therefore, you can calculate Cross Curves of Stability for any heeling axis. This is equivalent to rotating the model.
The HMMT command sets the heeling moment which is applied about the heeling axis. However, the WIND command uses only the lateral projection for the wind plane. Therefore, you cannot use HMMT WIND with the axis rotated.
For example, to get cross curves heeling about an axis which is rotated 30 degrees:
AXIS = 30
HMMT = 1000
CC 5, 6, ... 10

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