U-Boat Commanders Heard Destroyer Sonar Pings — Then Knew They Were Tracked From 20 Miles
One Letter a DayMarch nineteen forty-three. The North Atlantic is a graveyard. In the first twenty days of this month alone, ninety-seven Allied merchant ships have gone to the bottom. Over half a million tons of steel, fuel, and food meant for Britain. The U-boats are winning. Admiral Karl Dönitz commands over fou