I just tested it!
I ran a single mission dated in 1944 in my Type IIA 1944.
The goal was to sink some carriers in a task force, fiercly protected by destroyers.
I managed to sink one carrier.
After that I was under attack by british destroyers for over 2 hours real time.
They managed to DC my hull integrity to 76%.
No-one died though, and no-one was injured.
After 2 hours they left to join their force, and i surfaced.
GREAT BOAT!
Type II is now my favorite!