The Battle of the Bismarck Sea occurred March 2-4, 1943, when planes from the U.S. Fifth Air Force and the Royal Australian Air Force (RAAF) attacked a convoy of Japanese ships carrying troops and supplies to Lae, New Guinea. The bombing campaign ended with the destruction of four Japanese destroyers, eight Japanese troop transport ships, 102 Japanese fighter planes, and some 3,000 enemy soldiers.
To shore up their defenses in the Southwest Pacific, the Japanese Imperial General Headquarters made plans to send a convoy of ships from Rabaul, New Britain to Lae in New Guinea. The convoy would deliver troops, supplies, and aircraft fuel to New Guinea. The convoy also presented a threat to Australia, putting it at risk for a future Japanese invasion.
Allies monitoring Japanese radio messages intercepted and decrypted information about the convoy, and they began to plan an attack. The plan of attack called for long-range heavy bombers from the U.S. Army Air Force (USAAF), followed by anti-shipping aircraft from the RAAF and the USAAF once the enemy was within range. These planes would attack at medium, low, and sometimes very low (mast height) elevation.
Reconnaissance planes began sweeping the South Pacific, and on March 1, they spotted a concentration of enemy ships near Rabaul. Bad weather hampered reconnaissance but on the morning of March 2nd, the weather cleared, and aircrews spotted the convoy.
The attack started with a wave of B-17s dropping 1,000 lb. bombs. Crews reported successful hits with ships burning and explosions. Japanese destroyers plucked survivors out of the water. Ships that were not disabled continued churning towards New Guinea, and on the morning of March 3rd, the convoy was in striking range of the entire Allied forces.
A formation of Allied planes assembled over Cape Ward Hunt and attacked the convoy in three waves. The first wave involved Flying Fortresses that attacked from medium altitude, followed quickly by RAAF Beaufighters that dived to mast level, bombing and strafing the ships with machine gunfire. The third wave of bombers concentrated on sinking the ships. On March 4th, the US Navy sent patrol torpedo boats and aircraft to mop-up the operation. They engaged a Japanese sub trying to pick up survivors in the water.
The attacks sunk all eight Japanese troop transport ships, and four of the eight destroyers. Of the 6,900 Japanese troops headed to Lae, only 1,200 made it. Destroyers and submarines rescued another 2,700 and returned them to Rabaul. In a controversial move, Allies patrolled the waters for several days, strafing survivors in lifeboats. This was later justified as necessary to prevent the enemy from coming ashore.
The Battle of the Bismarck Sea was a devastating loss for Japan. Allied losses numbered four aircraft and 13 airmen. General Douglas MacArthur called it “the decisive aerial engagement of the war in the Southwest Pacific.” To learn more about the Battle of the Bismarck Sea, search Fold3 today!