I don't know the details of this sinking, but generally speaking it is hard to hear
when a u-boats pressure hull breaks because it tends to happen when the sound
is obscured by depth charges or the bubbles left by depth charges.
Aside from that, there is no "screen" for sounds in ww2 destroyers, just
headphones. Destroyers make a lot of noise and have a lot of "blind" spots. it would
be easy to miss any sound.
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