IIRC, things like this were being developed later in the war, but did not make it to the application phase. Remember that sonar, and radar were both still in their infancy, just like ASW was. Just like "smart bombs" made their debut in March of 1945, but they were too late to be of any benefit to the flagging Luftwaffe. And it took nearly 50 years of technical advancements in electronics to make them practical.
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A legislative act contrary to the Constitution is not law.
-John Marshall Chief Justice of the Supreme Court
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