Patents in WW2: US 2724817, FM Sonar

I thought I’d post about many of the interesting inventions from WW2, and the patent process leaves us with a wonderful historical record. Because it’s late and Christmas, I’ll keep it short, but here is the patent for FM Sonar, which was a game changer for the Allies because it made it much easier for them to track U-Boat positions. It also reduced the strategic advantage of U-boats altogether. The inventor, Hisserich, had previously been working in Hollywood studios as a sound engineer(