Having experienced the unpleasantness and expense of my catamaran mast going from vertical to fully inverted in a matter of seconds, I deemed it prudent to investigate masthead floats.
My first attempt was mounting two auto-inflate PFD's in a protective bag attached to the masthead. Also included was a swimming pool foam noodle stuffed inside the masthead. Total buoyancy was about 55 pounds. Unfortunately, twice at rest, in extended dry weather, a PFD inflated, leaving itself dangling high out of reach.
Simultaneously, good friend Russell Brown of PT Watercraft in Port Townsend, was experimenting with mast floats for his Gougeon-32 cat INCOGNITO. To replace his 7 pound "dirigible," Russ built an exquisite "Blimpie" that weighed in at 4.5 pounds, had an internal radar reflector, and rotated.
Blimpie saved Russell's bacon when INCOGNITO capsized in the rugged 2016 Round-the-County Race, and Russ was able to right his boat alone, without damage. https://www.youtube.com/watch?v=912H94--Xas Russell has gone on to complete two singlehanded R2AK races and return on INCOGNITO, and holds the R2AK singlehanded record time.
Across PT town, Brandon at Turn Point Design had built himself an all carbon, sleek and fast, 26' cat FELIX for the R2AK. At FELIX's masthead was a flat and streamlined UFO float, totally different in shape, and even lighter than INCOGNITO's Blimpie.
Recently, when Russell told me Brandon was building a new, lighter mast and mast float for FELIX, a deal was consumated with Brandon for his now surplus mast float, and I have mounted it on WILDFLOWER's masthead, complete with a Windex and burgee bracket. The UFO float is a single layer of 6 oz. carbon cloth and foam, weighs 3.5 pounds, and provides 60 pounds of buoyancy.
Congrats, BobJ, you have won the Macapuno!