Jan 1940 - The RAF introduces Identification Friend or Foe (IFF) signals to help identify Bomber, Coastal and Fighter Command aircraft on radar screens.
26 Jan 1941 - The Desert Air Force takes part in the Allied attack on Tobruk. Overwhelmed by the onslaught, the Italian Tenth Army is completely destroyed and the port falls within 48 hours.
26 Jan-30 Mar 1942 - The Japanese advance through the Far East. By the end of January, the RAF and other British and allied forces had withdrawn from Malaya and Singapore to Sumatra. Two weeks later, the enemy captured Palembang airfield in Sumatra destroying 39 Hurricanes in the process. By 18 February, the Allies had evacuated to Java. RAF aircraft in the area had been reduced to 18 serviceable Hurricane fighters, 12 Hudson, 6 Blenheim and four Vildebeest bombers. On 3 March, Allied forces began evacuating Java; those that remained capitulated the next day. In Burma, Japanese forces entered Rangoon on 8 March forcing the remaining RAF Hurricanes and Blenheims to move north. Finally on 27 March, the Japanese began a three-day assault forcing the Allies to evacuate to India. During these final days, Dakotas of No.31 Sqn and the USAAF airlifted 8,600 civilians to safety.
21 Jan 1943 - The Combined Chiefs of Staff issue the Casablanca Directive. Its principal aim was to weld RAF and USAAF strategic bomber forces into one mighty air arm able to crush the German industrial, military and economic system. It was also decided that to defer the cross-channel invasion until 1944.
21 Jan 1944 - The German Luftwaffe begin a series of heavy attacks on British targets, including London. Mosquito night-fighters equipped with radar account for 129 of the 329 aircraft shot down during the 5 month Little Blitz.
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Не все события приходятся на сегодняшнее число, но я позволил себе включить их посчитав их важными.