Specialized Missions Take Their Toll

The XXI Bomber Command devoted the rest of its sorties and tonnage to specialized missions performed by the 313th and 315th Bombardment Wings. On June 26, 1945, the 315th began a campaign against Japanese oil facilities. Over the next few weeks, it destroyed or heavily damaged Japan’s ten largest petroleum and synthetic oil plants, including much storage capacity. Although the B–29s bombed at night so that they could carry more bombs and fewer guns, they achieved a reasonable degree of precision with the help of improved radar (APQ–7). By early August, the 315th bombers had eliminated most of the enemy’s refining capability. Despite this success, some questioned the rationale for the attacks because the Allied naval blockade had already severely restricted the delivery of crude oil supplies to the refineries. 

For its part, the 313th Bombardment Wing on Tinian assumed another specialized mission—the aerial mining of Japanese waters to supplement the submarine blockade. Dubbed Operation Starvation, the mining was not an orthodox strategic air mission. LeMay supported Starvation, nevertheless, to demonstrate the versatility of air power. The 313th began systematic mining in late March 1945. Each B–29 carried 12,000 pounds of half-ton and one-ton mines. By mid-August, the bombardment wing had dropped more than 12,000 mines, most in the Shimonoseki Strait between Honshu and Kyushu, through which 80 percent of Japanese merchant shipping passed. The B–29s also mined Nakaumi Lagoon and the waters around Sakai, Yonago, Hamada, Wonsan, and other enemy ports. In less than five months, the 313th Bombardment Wing conducted 1,528 mine-laying sorties, losing only nine airplanes to enemy action. After April, the enormously successful B–29 campaign accounted for more Japanese merchant marine losses than did U.S. submarines. Superfortress-laid mines sank half of the tonnage the Japanese merchant marine lost during the war. The enemy lost 9 percent of her ships to the Twentieth Air Force. 

By August, the Twentieth Air Force had conducted 380 combat missions against Japan. Superfortresses released 147,000 tons of bombs, 91 percent of all bombs dropped on Japan’s home islands. B–29 attacks destroyed half of the enemy’s aircraft plant capacity and probably cost the Japanese 7,000 combat planes in lost production. In the process, the Twentieth lost 512 B–29s and 576 aircrew members. By August, more than 2,000 crew members were missing in action, but in the last month of the war, when the Twentieth Air Force had over 1,000 B–29s in the Pacific, only four Superfortresses were lost. 

The Twentieth Air Force did not have a monopoly on the bombing of Japan. After the Allies drove enemy forces from the Aleutian Islands of Alaska, the Eleventh Air Force established bases there. Using B–24 Liberators, the Eleventh bombed Japanese installations in the Kurile Islands northeast of Hokkaido as early as November 1943. After the fall of Okinawa to U.S. forces in April 1945, the Far East Air Forces (comprising the Fifth, Seventh, and Thirteenth Air Forces) established bases in the Ryukyu Islands, southwest of the home islands, from which to bomb Kyushu in preparation for the invasion of Japan. Okinawa was near enough to Japan for the Far East Air Forces to use B–24s and other warplanes smaller than the B–29.