Towing Criteria

In the towing criteria 46 CFR173.095 the residual righting energy should be calculated from 0 to MAX RA, FLOOD or 40 degree or it should be calculated from equilibrium to those limits?

2 ft.degree residual righting energy from equilibrium to flood/max/40 seems too liberal to fail.

can someone help me understand what the original intention was for this rule?

thank you

 

You must calculate the intersection between the curve of the righting arms of the ship and the curve of the heeling arms. The intersection marks the point of equilibrium. Equilibrium must be reached before the downflooding angle; and
The residual righting energy must be at least 2 foot-degrees (.61 meter-degrees) up to the smallest of the following angles:

• The angle of maximum righting arm.
• The downflooding angle.
• 40 degrees.

Although the figure talks about the case of water on deck, the concept of residual righting energy, how it is measured, is the same for your case.