@PaulGAllen: Pressure at bottom is 16,285 Pounds per square inch at that depth. Design pressure was 16,500 ...Yikes/Amazing!

Amazing that it is working. The engineering must be interesting.

Edit: Apparently the DC weighs a tenth as much as the Trieste (the original bathyscaphe), including all the instruments. Less than a lifetime. . .

> @PaulGAllen: Pressure at bottom is 16,285 Pounds per square inch at that depth. Design pressure was 16,500 ...Yikes/Amazing! Amazing that it is working. The engineering must be interesting.

I'd love to see a dissection of the submersible once they bring it back up. It'd be interesting to see if there were any seal or structural failures.

Just read that too. That's not much of a safety factor! Still, it's quite a feat and I hope it continues smoothly.

It's quite likely that the 16,500PSI rating is accounting for the safety factor.

16,500 PSI was just what it was tested at, and it could apparently withstand significantly greater pressure than that. From the Deep Sea Challenge website:

"The hull, complete with its hatch and viewport, was tested twice in a pressure chamber at Pennsylvania State University to an equivalent full-ocean-depth pressure of 16,500 pounds per square inch (1,138 bars). It passed both tests. Twenty-two strain gauges attached to the sphere gave data that indicated the sphere could withstand up to 140 percent of the test pressure without buckling."

You're probably right– at least, I hope you're right. Looks like everything went as expected though, so congratulations to everyone who worked on it. Still waiting to see what they collect...

Essentially no safety margin. I wonder what's normally considered reasonable.