K-350 1-man has 48" long cylinder, 2-man has 72"--the 600 is 72" in the 1-man version just to float. Built like an anvil. The PC-8 is a 42" diameter hull, 3/8" A516Gr70 and rated at 800', so I'd say Captain Kittredge was being very conservative. So would he. Vance