How quickly could a U-boat be scuttled?

How long does it take to scuttle a U-boat?

Opening the hatches and admitting water lets the boat sink quickly, but no precise duration is given and preventing recovery is more difficult.

A submarine can be sunk quickly by opening its hatches and admitting water into its tanks. Salt water then damages the boat's equipment. The harder objective is to leave it beyond recovery, since submerging a vessel does not itself establish permanent destruction. No measured time for the procedure is supplied.