US aircraft carrier USS Wasp returns to Glasgow, Scotland, following the delivery of Spitfires to Malta (Operation Calendar). USS Wasp quickly loads another 47 Spitfires for a repeat run to Malta (Operation Bowery).
In Famagusta Bay, Cyprus, British schooner Terpsithea hits a mine laid on April 13 by U-562. At 7.45 PM, tug Alliance goes to assist but also hits a mine and sinks (3 killed, 7 survivors).
At 4.12 AM in the Caribbean 50 miles West of Grenada, U-66 sinks Panamanian tanker MV Harry G. Seidel (2 dead, 48 survivors). 350 miles North of Puerto Rico, US tanker SS Mobiloil and U-108 engage in a running battle between 9 AM and 4.45 PM. U-108 finally sinks SS Mobiloil with the 6th torpedo (all 53 hands picked up 86 hours later by patrol craft USS PC-490 and landed on May 4 at San Juan, Puerto Rico).
Philippines. To celebrate Emperor Hirohito's birthday, Japanese launch a massive artillery and air bombardment of US positions on Corregidor Island. Further South on Mindanao Island, Japanese and US forces face each other across the island. Japanese land near Cotabato in the Southwest corner of Mindanao to eliminate the remaining US-Filipino garrison.
New Guinea. In order to gain air superiority over the Coral Sea and directly threaten the Australian mainland, Japanese plan to capture Port Moresby in Papua (in the Southeast of the island, currently administered by the Australians for the British). The Allies are aware of the invasion from deciphered Japanese messages. To contest the invasion, Admiral Chester Nimitz, commander of Allied forces in the Pacific, orders Task Force 17 (carrier USS Yorktown, escorted by 3 cruisers and 4 destroyers, commanded by Rear Admiral Fletcher) and Task Force 11 (carrier USS Lexington with 2 cruisers and 5 destroyers commanded by Rear Admiral Aubrey Fitch) into the Coral Sea.
Burma. As British and Chinese resistance collapses, Japanese swarm North. 18th Infantry Division captures Kyaukse, 20 miles South of Mandalay. Further West, 33rd Infantry Division crosses to the West bank of the Irrawaddy River to pursue the British retreat towards India. Japanese have been planning for 3 weeks to take Lashio (the busy terminal of the Burma Road) by parachute drop. Japanese paratroops of 1st and 2nd Raiding Regiments fly over Lashio in the morning but cannot make the drop due to bad weather. However, the town is taken later at noon by ground forces of 56th Infantry Division.
Overnight, 88 RAF bombers (73 Wellingtons, 9 Hampdens, 6 Stirlings) attack the Gnome & Rhone aero-engine factory near Paris (1 industrial building destroyed and 3 more damaged, no civilian casualties, 3 Wellingtons lost). Baedeker Blitz; Luftwaffe bombs Norwich on the East coast again.