Day 963 April 20, 1942

USSR. After a month of fighting since March 21, German forces under General Walther von Seydlitz-Kurzbach break out of the Demyansk pocket through the "Ramushevo corridor". Of 100,000 Germans trapped in the pocket, 3,335 have been killed and 10,000 wounded. The airlift to supply the troops since February 8 has cost 265 Luftwaffe aircraft (including 106 Junkers Ju52, 17 Heinkel He111 and 2 Junkers Ju86) and 387 airmen while Soviets have lost 408 aircraft, including 243 fighters. The successful supply mission and subsequent breakout convinces Hitler and Göring that holding large pockets can tie up large Soviet formations; they will try the same tactic at Stalingrad, later in the year.

At midday, 1.5 miles off the Norwegian coast near Namsos, British submarine HMS Trident sinks the German freighter SS Hödur.

Operation Calendar. US aircraft carrier USS Wasp's contingent of Grumman F4F Wildcat fighters provide air cover for the take off of 48 Spitfires flying to Malta. However, Luftwaffe is aware of the fighter shipment and bombs Ta'Qali airfield before the Spitfires can refuel (20 destroyed and 12 severely damaged on the ground). The remaining Spitfires are destroyed by further attacks within 48 hours.

Off the US East coast, U-654 sinks Swedish MV Agra (carrying 6666 tons of supplies, nitrate, trucks and drums of fuel to Allied troops in Egypt) and US freighter Steel Maker (carrying 7660 tons of lend-lease supplies to USSR via Iran), U-572 sinks British SS Empire Dryden (also carrying 7000 tons military stores to Egypt) and U-109 sinks British SS Harpagon (carrying 8017 tons of supplies, explosives, aircraft and tanks to British forces in Bombay, India). 75 miles North of the Turks and Caicos Island, U-154 sinks Canadian SS Vineland (in ballast).

Burma. Japanese make good progress as they push North to threaten the Burma Road to China. Burmese 1st Infantry Division and Chinese 38th Division withdraw North from Yenangyaung. Japanese 18th Division attack Chinese positions at Kyidaunggan on the road to Mandalay while Japanese 56th Division captures Loikaw on the road to Lashio.

Bataan. Japanese bring up the massive WWI-era Type 96 240mm siege howitzer to shell US artillery on Corregidor.