Re: [PSUBS-MAILIST] Hatch design

[VBra676539@aol.com]

Herman,

The dome hatch on Captain Kittredge's K-250 design is rated for an operating depth of 250 feet. It is plexiglas, which has much healthier characteristics under pressure than lexan, and cost, the last I heard, about $800 US. They can be ordered from a fabricator in Maryland, recommended by the designer.

One of the early K-250s was tested in a tank to destruction. Captain Kittredge had calculated that the dome would be the first thing to go, and it was. At 800-plus feet!!! Still, to be conservative, he has limited the designed operating depth to 250 feet. If you want to go deeper, you will need to redesign with thicker material (the K250 is made from one inch material) or go Kittredge's K-350 design route, which gives you an all steel conning tower with four viewports in the cylinder and one in the hatch. The K-350 tests to 500 feet unmanned to verify strength and operability. I am not sure what is called for to test the K-250.

The dome builder could probably fabricate whatever you wanted, and if you had someone on tap to redesign the retaining ring structure you could probably go deeper with a heavy duty version on the K-250. 

Diving to 100 meters off Malta sounds very good indeed, although you might think the same of my backyard on the Treasure Coast of Florida, or the Keys, 2 hours away. Or how about a psub rodeo in Hawaii? We've got a connection out there. I wonder what the airlines would say about our excess luggage? I can see it now. "Say, young feller, how much does that big box weigh?" Psubber replies (sheepishly): "....er....2 tons, sir. Is that over the carry on limit?"

Best Regards,
Vance Bradley