Home Page Gallery Timeline 1939 Timeline 1940 Timeline 1941 Timeline 1942 Timeline 1943 Timeline 1944 Timeline 1945 Navy News Email Update Enter your Email address to stay Up-to-date with our great news letter.		The Battle of the Atlantic - Timeline - 1944   < back Jan: Doenitz sent out two U-boat groups with new schnorkel breathing device but both are attacked. May: Doenitz restricted schnorkel subs to immediate water around Britain to avoid radar.