Hello BROJD,
There was no single ‘war winner’ weapon introduced by the Allies, so I would like to make a suggestion. May 1943 was a turning point in the Battle of the Atlantic because of collective improvements in tactics and equipment of the Allies, yet in the months leading up to that date the U-boats were effective. The story is told in a thorough and scholarly manner in ‘Black May’ by Michael Gannon (ISBN 0-06-017819-1). He quotes his references generously and explains each of the factors that lead to the scales tipping in a clear manner. You may find a good amount of inspiration, and the tools to do the job, in that one book.

Hope this helps,
Bruce

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