Deepest I've Ever Gone...Think It's A Subsim Record

[UKönig]

Originally Posted by ridley

I hope that was not a live test.

The books I've read said "simulated depth test", but I'm not 100% certain of how. In the days before computer modelling, tests to destruction meant literally that. For example, in the mid to late 1950s, the British were losing "comet" jet airliners to an unknown cause. They put one of the air frames into a giant tank of water and started filling 'er up. Finally the hull failed and that's when they discovered that the square window frames were putting too much stress on the structure, from the constant pressure changes, and from that point on, (as you can see this today) all aircraft that operate at altitudes over 10,000 feet have rounded window frames.
I assume something similar was done to test surrendered​ or captured U-boats