[Schöneboom]

Jeepers, I didn't know such extended encounters were possible in GWX! I've only had to tangle with convoy escorts who, if they lose contact with you, give up after about 1-1/2 hrs. Those DDs you're dodging must be independent hunter-killer groups, right?

In a sick way, I almost envy you. I would be amazed to be in a tight spot with my air & battery power running out! To add to Graf Paper's advice, I would add only:

1) If there is no thermal layer to protect you from the DD sonar, then you might need to jump to full speed as soon as your sonarman yells, "Wasserbomben!"
2) The explosions mask your noise for ~30 seconds, so soon after the last explosion, switch back to 1 knot & change course. Then stay silent until the next attack.
3) If you are under a thermal layer (can't hear the pings), then you stay at 1 knot until the explosions start.

Viel Gluck!