[PSUBS-MAILIST] pressure hull sizing

[DBACKIDS@aol.com]

I am currently in the process of designing (no hopes yet of building, only design) a small two-man sub called the Manta, taking its name from the design similarity to the manta ray. My question is: would a seven foot diameter sphere be large enough to seat two people with a control system comfortably? (I'm quite sure five feet would be too small, but I don't envision spheres very well–they're such an awkward shape, lol)

David C