On 14 June 1944, Boeing B-29 Superfortresses struck for the first time at the Japanese home islands. Most early raids were made at high level (above c.30,000ft, 9150m), but although Japan’s air defence was deficient in both AA guns and aircraft with the speed and combat ceiling successfully to intercept the Superfortresses – of 414 B-29s lost, only 147 fell to Japanese interceptors or AA fire – it was felt that the results of such operations did not justify even the lowest loss rate.
Early in 1945, MajGen Curtis LeMay took over the Marianas-based 21st Bomber Command from BrigGen Haywood Hansell, adopting a policy of low-level incendiary raids at c.5–6,000ft (1500–1800m) by B-29s virtually unarmed for extra speed. By August, LeMay could claim that fire raids had completely shattered some 58 major cities and that by bombing alone Japan would soon be “beaten back into the dark ages”. Fire raids indeed caused far greater material and moral damage than the two atomic bombs: on 9–10 March, in a raid by 325 B-29s, 15.8 sq miles (41 sq km) of Tokyo were gutted and c.84,000 killed and more than 100,000 injured (compared to c.78,000 dead and 68,000 injured in the atomic blast at Hiroshima). In a fire raid on Toyama on 1–2 August, no less than 99.5 per cent of the city was devastated. And when Prince Konoye told the USSBS that the major factor in Japan’s decision to surrender was “fundamentally ... the prolonged bombing by the B-29s”, he was speaking of the fire raids. One Japanese statesman, however, referred to the atomic destruction as “the big kamikaze that saved Japan”; meaning that the terrible civilian casualties sustained in just these two strikes afforded a decisive argument to the peace faction.
With fuel stocks low, factories and repair facilities dislocated, and many aircraft lacking trained pilots or held in reserve for the final kamikaze onslaught, the Japanese air arms proved unable to deal effectively with the low-level raiders and thus increasingly resorted to suicidal aerial ramming interceptions. Isolated instances had occurred earlier in the war. On 4 July 1942, Lt Mitsuo Suitsu, enraged when his naval air squadron’s field at Lae, New Guinea, was badly damaged by US bombers, fulfilled a vow of vengeance by destroying a Martin B-26 Marauder in a head-on collision with his Zero. The first Army pilot credited with such self-sacrifice was Sgt Oda who, also flying from New Guinea and unable to maintain the altitude conventionally to engage a B-17 that was “snooping” a Japanese supply convoy, brought down the Fortress by ramming with his Nakajima Ki-43 “Oscar”.
Tai-atari (“body-crashing”) tactics were not invariably fatal: a few US bombers were destroyed by Soviet-style Taran attacks, their tail assemblies chewed away by fighters with armoured propellers. USAAF personnel reported the first cases of what they judged to be deliberate ramming during a raid on the steel works at Yawata, Kyushu, on 20 August 1944. Of four bombers lost over the target area, one fell to AA, one to aerial gunfire, and two to a single Kawasaki Ki-45 Toryu (Dragon Killer; “Nick”): the “Nick” rammed one B-29 and the debris of the two aircraft brought down another.
In February 1945, an IJA manual stated that against B-29s (and the expected B-32 Dominators, of which only a handful became operational) “we can demand nothing better than crash tactics, ensuring the destruction of an enemy aircraft at one fell swoop ... striking terror into his heart and rendering his powerfully armed planes valueless by the sacrifice of one of our fighters”. The manual noted that only partly trained pilots need be used and recommended as rammers the Nakajima Ki-44 Shoki (Demon; “Tojo”) and Kawasaki Ki-61 Hien (Swallow; “Tony”), on the dubious grounds that their designs gave the pilot a faint chance of baling out immediately before impact.
Earlier than this, in November 1944, the 2nd Air Army’s 47th Sentai formed the volunteer Shinten Sekutai squadron, dedicated to ramming attacks in “Tojos”. Their successes included the destruction of a B-29 over Sasebo on 21 November by Lt Mikihiko Sakamoto; another B-29 on 24 November (one of only two Superfortresses brought down in a 111-strong raid); and two B-29s (out of only six lost from a 172-strong force over Tokyo) on 25 February 1945. Fighters of the Kwantung Army also adopted ramming tactics, bringing down two B-29s over the Mukden aircraft works on 7 December 1944 and another on 21 December. On both occasions, Japanese aircraft also attempted air-to-air bombing, releasing time-fuzed phosphorus bombs above the US formations. At least one B-29 was destroyed by this method, which was also used in the defence of the homeland.
A less extreme measure than ramming was the formation at Matsuyama NAFB, Shikoku, in January 1945 of a fighter wing led by Capt Minoru Genda and including Saburo Sakai and other “aces”. Flying the Kawanishi N1K2-J Shiden (Violet Lightning: “George”) – probably Japan’s best interceptor; only c.350 were built – they achieved especially good results against Allied carrier strikes. On 16 February, WO Kinsuke Muto was credited with engaging single-handed 12 F6F Hellcats from USS Bennington over Atsugi, Tokyo, shooting down four and driving off the rest.