Post mortem: I ran out of oxygen while trying to get to the surface, though I certainly would have been demolished had I suceeded in getting there, as I was surrounded. I thought it was interesting that I received the "instant death" screen, indicating "Not enough crew".
I took a look with the external camera just before all of my crew died at the same time. One of the escorts had moved off. The remaining five were three Tribal class Destroyers and two C-Class Destroyers.
Ouch.