Gaff Masts - replace timber with aluminium

If 2/3 of the mast height is 40 feet, a 180 lbs crew will create a moment of 7200 ft/lbs (about 7200 Nm) at 1G acceleration. Even at a more moderate rolling, say .3 G it is quite considerable.

 

The error in that calculation is is the 1G acceleration, and even 0.3g. The way to do it would be to start with the current oscillation frequency and use that to calculate the acceleration, or better yet energy.

The current period is likely over 4s. I would guess more like 0.2g or 1440 ft.lb at a +/- 20 amplitude.
Tell a typical sailor you can take that much weight out of his rig and his first words will be "make it taller".

 

Having work aloft many times, I thing that 0.3G is conservative. The easiest way to calculate it would be to know the period and amplitude.

 

Agreed.
I think it just feels like like more, and any fool that says less gets the job of going up the mast.