At 3.55 AM 300 miles East of Cape Hatteras, North Carolina, U-123 (out of torpedoes and with only 29 rounds for the deck gun) closes on the surface to 400 meters and sinks US freighter SS Alcoa Guide with the deck gun plus 37mm and 20mm anti-aircraft guns (6 dead, 27 survivors in lifeboats picked up on April 19 by US destroyer USS Broome, 1 man on a raft picked up by British SS Hororata after 30 days). At 5.23 AM 100 miles West of Grenada in the Caribbean, U-66 sinks Panamanian tanker Heinrich von Riedemann carrying 127,041 barrels of crude oil (all 44 hands escape in 3 lifeboats).
RAF Bomber Command experiments with an ill-conceived daytime raid to achieve accurate bombing. 12 Avro Lancaster bombers (6 each, 44 & 97 Squadron) fly at low level without fighter support to attack the MAN diesel engine factory at Augsburg in Southern Germany (450 miles from the French coast). Diversionary RAF raids in Northern France fail to distract Luftwaffe fighters, which shoot down 4 Lancasters. Anti-aircraft fire downs 3 more Lancasters over Augsburg. 7 Lancasters release their bombs over the target, causing minimal damage. Squadron Leader Nettleton (44 Squadron) wins the Victoria Cross for leading the raid and nursing his badly damaged aircraft home.
German bombers sink Soviet troopship Svanetiya carrying troops from Sevastopol to Novorossiyks in the Caucasus (750 killed. 193 crew and passengers rescued).
Burma. Chinese General Sun Li Jen leads 1121 men of 113th Regiment (38th Division) South to relieve 7000 British and Indian troops trapped by Japanese 33rd Division around Yenangyaung. British General Slim send British 7th Armoured Brigade North across the Pin Chaung River (before the Japanese ring closes) to meet up with the Chinese who lack tanks and artillery. Further East, Japanese 56th Infantry Division heads 45 miles North from Mawchi to Bawlake, whence they can threaten the Burma Road (the important supply route from India, through Burma into China) between Mandalay and Lashio.
Panay, Philippines. Japanese troops and light tanks head North from Iloilo City and South from Capiz across the flat Iloilo Plain. They meet at Dumarao, 30 miles South of Capiz (now known as Roxas City), and control the Eastern half of the island.
Overnight, 173 RAF bombers (134 Wellingtons, 23 Stirlings, 11 Halifaxes, 5 Manchesters) attack Hamburg, Germany (starting 33 fires, 23 civilans killed, 66 injured). 7 Wellingtons and 1 Manchester are lost. Luftwaffe bombs Southampton, England, overnight.