Either you have 70% hull integrity, which means you only lost 30, or you have 70% hull damage, and you have only 30 left.
IIRC, The game shows Hull integrity remaining.
In either case, that means you wont be able to dive as deep, or your boat will be crushed. because of your weakened hull.
You can only repair hull integrity if you end patrol at your home port. Refit just means you get ammo and fuel.
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A popular Government without popular information nor the means of acquiring it, is but a Prologue to a Farce or a Tragedy or perhaps both. Knowledge will forever govern ignorance, and a people who mean to be their own Governors must arm themselves with the power knowledge gives
- James Madison
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