[riversflow]

What?

> Alvin enables in-situ data collection and observation by two scientists to depths reaching 6,500 meters, during dives lasting up to ten hours.

Maybe you misskimmed:

> Alvin is a proven and reliable platform capable of diving for up to 30 days in a row before requiring a single scheduled maintenance day

[SV_BubbleTime]

I did skim! :) Don’t do that.