With all the problems of delamination, UV damage, need for high strength and low weight, etc., I was wondering why no mfr. seems to ever fabricate hulls in aluminum? Crossbars are already Al, so no dissimilar metal problems there.

It's pretty amazing that the voluminous Prindle-16 hulls are only 90 lbs. each, and I was wondering if that volume/weight ratio could be matched with aluminum?

Right off the bat I'm thinking you couldn't execute the same complex shapes and compound curves in Al that you can in GRP... OTOH, some cat hull shapes are pretty simplistic.