[fargle]

The reason it's a useless terrible material for a sub is that until it survives the first dive, you don't know if it has a hidden flaw.

And after the first dive, even if it survives, you know that 100% that it does.

Weight is not nearly the problem it is for a sub as it is for spacecraft or aircraft. The problem wasn't safety protocols or XBox controllers or any of that. It was conflation of "big idea people"[1] with real engineers.

[1] see Jobs, Musk, etc.

[midoridensha]

As I said, I'm an armchair observer here, not a materials scientist.

However, there are a lot of things that are absolutely designed and built to be single-use, especially in fields like space, where rocket engines have been single-use until very recently.

As for weight, I think the reason that was important was because they didn't have a big enough ship that could operate a crane and haul the submersible out of the water. Really, the whole operation was a bad idea: this kind of exploration is expensive as hell, and the only way to cut costs (with current tech) is to do really dangerous stuff.