Vance, My issue is not that they survived but it is my feeling that there are stability and maneuvering issues. This is an opinion that I don’t have the time to work out the calculations to support. Would think that if it was a successful hull form that there would be many more built due to the economy and innate strength of this shape. The ride on the surface would have to be particularly obnoxious due to pitching and heaving. R/Jay From: owner-personal_submersibles@psubs.org [mailto:owner-personal_submersibles@psubs.org] On Behalf Of vbra676539@aol.com The FIRST saucer pressure hull was lost at sea, along with an expensive set of strain gauges. Sat 10 meters off the seabed at a thousand meters for over seven years before finally leaking down and settling into the grave. Vance Vance, From a historical point, how many saucer-shaped submersibles were operational successful (and this is not to be negative on Frank’s extensive effort…I am praying that it is successful after all of his hard work)? There is Cousteau’s saucer (the 2nd saucer was last at sea) and the unsuccessful Boston effort the I am personally aware of. Past history is not real supportive of saucer-shaped submersibles. R/Jay From: owner-personal_submersibles@psubs.org [mailto:owner-personal_submersibles@psubs.org] On Behalf Of vbra676539@aol.com Frank, When you were looking for hull bits, did you find a fabricator who could and would do non-standard elliptic heads? I'm fiddlig with the old Diving Saucer shape, which was 1.5 meters by 2 meters, give or take an inch, and was 3/4" thick. I like the space and payload available with that shape. A 2:1 head gives you, what, four feet in height? I don't remember the thickness of your hull. What does the shell weigh and what depth are you figuring for test and operating? Vance |