Historical File: Sept, 1940 Battle of the Atlantic

Early in the September German "wolf-packs" attack two convoys: In convoy SC2, five of the 53 ships are sunk. Against convoy HX72 11 out of 40 are sunk - with "U-100" sinking seven in one night! The U-Boats do most of their attacks on the surface at night when they are almost invisible. The escort ships discover a key problem: they urgently need better radar so they can detect U-Boats on the surface, and force them to dive and lose their speed advantage. Once a U-Boat goes underwater the escorts can locate them with their ASDIC and attack with depth charges.