If you know target course and speed and you're close enough it is "doable". It all comes down to an estimation of "lead angle" for a zero torp gyro angle firing attempt and getting close as possible. Close range eliminates the effects of inaccuracies in target course and speed estimations. It is a calculated risk situation based on the time the escorts will effectively react on the sub's precence and the fact that a "safer" approach would probably lead to a "low odds" attack or even none at all.
Then you die
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