<P> Attacks on airfields and transportation infrastructure in southern Japan continued until the end of the war . By this time the Fifth Air Force's bombers had flown 138 sorties against airfields in Kyushu and the Seventh Air Force had conducted a further 784 . Road and railway bridges were attacked by both fighters and bombers, and the city of Kagoshima was frequently bombed . Seventh Air Force B - 24 Liberators also bombed the railway terminals in the port of Nagasaki on 31 July and 1 August . While these raids were focused on tactical targets, the Okinawa - based aircraft made several strategic attacks against industrial facilities; these included an unsuccessful raid on a coal liquefaction plant at Ōmuta on 7 August . Bombers of the Fifth and Seventh Air Forces also made firebombing attacks against Tarumizu on 5 August, Kumamoto on 10 August and Kurume the next day . The FEAF staged its last attacks against Japan on 12 August; aircraft were dispatched on 14 August but recalled while en route to their targets . Overall, the two air forces flew 6,435 sorties against targets in Kyushu during July and August for the loss of 43 aircraft to Japanese anti-aircraft guns and fighters . </P> <P> Japan's air defenses were unable to stop the Allied air attacks . Owing to the short range of the country's land - based radar, and Allied attacks on IJN picket ships, the defenders typically had only about an hour to respond to incoming B - 29s once they had been detected . Japanese signals intelligence units could provide longer warning times of incoming raids by eavesdropping on the bombers' radio communications, but were unable to predict the target of the attack . As a result, fighter units did not have enough time to scramble and reach the bombers' cruising altitude before they arrived over their target, and most raids were intercepted by only small numbers of aircraft . Moreover, the American bombers were capable of flying faster at high altitude than many Japanese fighters . Even when the fighters managed to close within gun range, the well - built B - 29s were often able to sustain large amounts of damage . Due to the difficulty of intercepting and downing B - 29s, the Japanese fighter pilots increasingly perceived their efforts as being futile . From August 1944 Japanese aircraft occasionally conducted suicide ramming attacks on B - 29s, and several specialized kamikaze fighter units were established in October; by the end of the war, ramming tactics had destroyed nine B - 29s and damaged another 13 for the loss of 21 fighters . </P> <P> Air combat was most intense in late 1944 and early 1945 . Following the first B - 29 raids on Tokyo, the number of IJN aircraft assigned to air defense duties was greatly increased and all 12 - centimeter (4.7 in) guns were allocated to protect the capital . Fighters stationed to defend Japan's main industrial areas frequently intercepted American air raids between 24 November 1944 and 25 February 1945, and inflicted significant losses for a period . The number of fighters available declined from late January, however . Poor coordination between the IJAAF and IJN also continued to hamper Japan's defensive efforts throughout this period . The Americans suffered few losses from Japanese fighters during the night raids which were conducted from March 1945 until the end of the war . </P> <P> Resistance to the air raids decreased sharply from April 1945 . On 15 April the IJAAF and IJN air defense units were belatedly placed under a single command when the Air General Army was formed under the command of General Masakazu Kawabe, but by this time the fighter force's effectiveness had been greatly reduced due to high rates of casualties in training accidents and combat . Due to the poor standard of the remaining pilots and the deployment of P - 51 Mustangs to escort B - 29s, the Japanese leadership decided in April to withdraw their remaining fighters from combat . These aircraft were placed in reserve to counterattack the Allied invasion . As a result, few of the subsequent Allied raids were intercepted . The effectiveness of Japanese anti-aircraft batteries also decreased during 1945 as the collapse of the national economy led to severe shortages of ammunition . Moreover, as the anti-aircraft guns were mainly stationed near major industrial areas, many of the raids on small cities were almost unopposed . Imperial General Headquarters decided to resume attacks on Allied bombers from late June, but by this time there were too few fighters available for this change of tactics to have any effect . The number of fighters assigned to the Air General Army peaked at just over 500 during June and July, but most frontline units had relatively few serviceable aircraft . During the last weeks of the war Superfortresses were able to operate with near impunity owing to the weakness of the Japanese air defenses; LeMay later claimed that during this period "it was safer to fly a combat mission over Japan than it was to fly a B - 29 training mission back in the United States". </P>

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