Or can anyone suggest one I could consult? I am making tabs to mount on either side of the transom for a Jordan Series drogue, similar to the ones on Morgan's Cloud pictured in the link below. The drogue manufacturer, Ace Sail makers, says for my displacement (~11T fully loaded) I need to plan on 14,000# total load and about 10,000# (70%) load on either bridle. They specifically state that "for a load of 14,000 lbs, a strap ¼ x 2.25 x 18 inches attached with six 3/8 bolts would provide a conservative design." I am planning to make a SS strap 1/4 x 2.25 x 20, attached with six 3/8 bolts and backed with a piece of G10 bonded inside the hull, and use 5/8" Crosby G-209A shackles which have a SWL of 10,000#. I am leaning towards making a slot for the shackle, so that it can be inserted and turned so the opening faces aft, and the rounded end of the shackle is forward (opposite to the one pictured on Morgan's Cloud). This will better enable the shackle to rotate laterally as the boat yaws and avoid excessive torque on the shackle pin. To mount the shackle in this manner I need an opening slightly bigger than .63" high and 1.5" long. My question would be, if I make a slot .75" high and 2" long, am I leaving enough material to maintain the structural integrity of the tab? Also, what is the minimum amount of material needed aft of the slot?

Thanks, Max

ACE website:

http://www.jordanseriesdrogue.com/D_5.htm

Morgan's Cloud design:

http://www.morganscloud.com/2009/06/01/jordan-series-drogue-launch-system/#comments