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    The Ki-43 was Nakajima's designation for the fighter design to replace the Ki-27 ("Type 97"/1937) fighter code-named Nate. The Ki-43, Type 1 (1940) Army Fighter, known to the Japanese as the Hayabusa, and code-named Oscar by the Allies. It was a slow, fragile and lightly armed, but an extraordinarily maneuverable, fast climbing plane of fame. Although it was very vulnerable in battle, most who flew it would agree it was a beautiful airplane to handle. Production started in 1941 and continued until 1944, with 5,751 aircraft produced.

    Its development was ordered by the Army shortly after the Nomonhan Incident, a 1939 battle, which resulted in the defeat of the Japanese Sixth Army. Nakajima Aircraft, of Ota, Gunma Ken, builders of the Ki-27, were to develop a two-gunned retractable geared light fighter of equal maneuverability to the Ki-27. (At the same time a development order along concept lines of a higher wing loading, faster and harder hitting attack fighter was issue to the same firm. This was to become the later Ki-44 Type 2 Army Fighter, the Shioki or Tojo.)

    Designer Hideo Itokawa, (who passed away in Feb 1999) undertook the difficult task of equaling the Ki-27's tight-turning and dogfighting qualities in a heavier 1,000 horsepower (745 kW) class fighter. He came up with a similar low winged all metal monoplane of very light construction with the Nakajima 12% in-house airfoil similar to the Nate's and, similarly armed (at first) with two 7.7 mm machine guns atop the cowl that the Army had so adamantly called for. (Nakajima staff and others were convinced that the trend in the world was toward four and six, even eight gun fighters, with 12.5mm machine gun and 20mm aerial cannon armament, but the Japanese Army Generals scoffed at the air superiority fighter concept and had a ground-based, political and ideological concept of warfare perhaps shaped by their Chinese adversaries. Anyway, they needed a new plane and wanted a lightweight, tight-turning dogfighter for an army support/counter insurgency role. (Oscars did find their way into French hands against the Viet Minh after the war and other counterinsurgency roles elsewhere then!) This despite frightful losses at Nomonhan where the 1st, 64th and 11th Sentai held onto aerial superiority by their fingernails in the Ki-27, winning literally a "Pyrrhic Victory" (as in funeral pyre, not Pyrrus of Epirus) against the heavily armed and armored Soviets and were slaughtered by Chennault's tactics in the early Curtiss P-40s over the North China plains and Mongolian grasslands. The new airplane went through a year-long development program entered production in early 1941 as the Ki-43 with a 950 hp (708 kW) Nakajima Ha-115 twin row radial engine turning a Sumitomo-Hamilton two-blade licensed propeller.

    Designer Itokawa turned to a sophisticated flight control technology in the form of "butterfly shaped (actually paddle shaped) air combat maneuvering flaps" that were deployed from Bowden levers atop the control stick (like the brake on a Nanchang) creating lift to overcome high load factors and augmenting the ailerons. At that time the more air-minded Japanese Navy had a world class fighter with its Type 0 (1940) Mitsubishi A6M Zero shipboard fighter, proven against the latest Soviet designs in the Hainan and South China region before the Navy pullout from China in late 1941. (They did come back, and soon, to Hainan and Shanghai, and Zeros had a very long range for regular sweeps deep into China proper, and a detachment was based in the Kunming area before long.) In 1940 though the Army in North China was barely holding on with its Ki-27 against the P-40 and the Polikarpov I-16 with their hard-hitting tactics and speed, and desperately needed the new plane.

    The Oscar was to change that, but not to the extent hoped. Superior marksmanship/airmanship was to make up for the lack of heavy guns. This clever hope failed to materialize. The plane's light wing loading and fundamentals limited its top speed, diving ability and punch. Light armament dogged the design to the end, and doomed its pilots as well, and not for a lack of trying...the design could simply not carry more guns, not on pylons, not anywhere, although it was tried desperately down the years (finally with an unsuccessful nose-stretch for twin cannon.) as time ran out for Japan. But the beautiful, if fragile, Oscar created its share of havoc and horror for Allied airman upon the outbreak of hostilities and down to the end of the war. Beside its simple pure beauty as an aeroplane, it had a number of strengths. For one it was stable, predictable and easy to fly, land, approach in and handle on the ground. It spun safely in any configuration and was used as a trainer extensively. For another it had a fantastic rate of climb and the tightest turning radius of the entire pack. Although it lacked the Zero's top speed and wing-cannon punch, it turned inside of it and climbed faster, with the same power in the respective airframes. Weak firepower and inadequate Army pilot training and tactics/philosophy were to blame for the Oscar's lack of success relative to the Zero. Still, Oscars shot down a frightful number of Allied planes and airmen right down to the end, (suffering high attrition themselves for the above reason and backwards fighter tactics) and were a mainstay (along with the Ki-84 Frank) of the Army's large "Special Attack" (Kamikaze) program. They were found in nearly every region of the Pacific and in very large numbers in China.

    But perhaps the greatest advantage the Oscar had over its contemporaries (and shared with the P-51 Mustang, Zero and Frank) was its RANGE. It was an extremely long-legged airplane and its pilot was under little stress about time as a result. With its large wing tanks and external stores it was an extremely long ranged fighter airplane, not unlike the P-51. It had a huge radius of action and the pilot never felt under constant pressure to figure out just where he was and to plot a hurried course home, with its attendant distraction. For example, an Oscar or Zero out of Taiwan could reach the Philippines, fly and fight for 30 minutes and return to base with reserve fuel. This was an important lesson of the Battle of Britain; all those Messerschmitt Bf 109s that never made it home for want of fuel, and Itokawa (and Mitsubishi's Horikoshi) took note. The location of the tanks in the wings and under the cockpit, without the dangerous forward fuselage tank, made the plane more survivable in combat or operational accidents; they didn't catch fire as easily as the Zero. On the negative side, there was a certain structural weakness in high G pullouts and a reluctance to recover from terminal velocity dives. They couldn't dive that fast anyway, so it wasn’t easy to pursue a diving P-40. And then allied aircraft got faster as we all now know. The qualities that made it a delightful plane to fly and climb in and a dog in a dive make it a fine flying model subject...it is among the planes that tend to go UP, not DOWN, given a knowledgeable flier of course.

    In aerial combat the Oscar was often mistaken for the Zero, and poor allied intelligence failed to spot the type in time to create training materials. The Ronald Reagan training film on Zero vs. the P-40, identification at a base in the CBI theater warned pilots to look for "the cigar shape fuselage" with the fin on top" as opposed to the stab atop the fuselage and deeper rudder of the P-40....and the Oscar! There were few if any Zeroes to be seen in South China at precisely that time. This despite the Oscar's having become a main propaganda piece for Japanese internal consumption. The overnight training of thousands of Japanese linguists at bases in the USA and the creation of a monumental signal intelligence program ended such darkness about Japan quickly, but the Oscar had snuck through unnoticed when the Allies were caught unprepared, victims of their peaceful intentions. Perhaps Allied pilots in China assumed it was a type of Zero or just called everything a Zero; the capabilities were similar except for the firepower. Both aircraft became obsolescent quickly at any rate.

    The fuel tanks weren't self sealing, but than neither were most of the others (Brewster Buffalo, early P-40 and P-51, etc.) in 1941. The first unit to change over from the Nate to the Oscar was the famed "Hayabusa" (Peregrine) 64th fighter wing famed for the red falcon under their Ki-27 cockpits, which had policed the North China skies since 1938 and made quite a name in the Japanese press for their exploits against the Chinese AF as well as Soviet and American Volunteers. Hence the new plane was named "Hayabusa" by the Army's publicity men and the press and they tried to regain their lost prestige (vis a vis the Navy's Zero) with the new ship. It was hardly a secret! Needing glory and recognition before the public, the Army played up the Oscar with a feature motion picture and a pop song from it: "The Kato Hayabusa Fighter Wing" about the 64th. It's on the Japanese language Karaoke menus, usually with a cool video, ask if you frequent one of those haunts. The transition was conducted under the leadership of the famed China ace, Major Tateo Kato, who led the 64th, a mixed force of Oscars and Nates then, in their victorious sweep into Southeast Asia, against mostly British Commonwealth forces in Buffaloes, Mohawks and Blenheims. Still the Japanese fliers were shocked by the tenacious resistance and resourcefulness of the Allied fliers who made the best of their outclassed machines and quickly found the weak spots of their enemy. A few Commonwealth aces were made in the Buffalo/Mohawk (P-36) vs. Oscar war, including the famed George Fisken (sp) of New Zealand, Buffalo ace.

    In a short while, the 64th was recalled to Japan for training and ongoing re-equipment with a new version of the Hayabusa the Series/Mark2 of the Type 1 fighter with a slightly shorter wing and other refinements, to make the movie. In April 1942, Major Kato in his original Mark 1 machine with the bordered cobalt diagonal wing stripes and arrow on the fin, led his flight of 12 Oscars in an attack on a Blenheim of RAF 64 Squadron off the Burma coast. The gunner on the Blenheim picked them off one by one like ducks in a shooting gallery as they followed each other to their deaths in a doomed diving attack of the bomber with its blazing turret and determined gunner. The crippled plane was down on the waves dodging the attacks with fuel streaming from its riddled wings when Major Kato, the last attacker, was hit and dove into the sea.

    Only about 750 of the original Series/Mark 1 long winged aircraft were built. The Series 2 was most common, built by Tachikawa and Nakajima, with oval air intake atop the cowl and slightly shorter wing, cleaner canopy, and the final Series/Mark 3 (never 'Type'3, that's a Tony) with water meth filler in the canopy and rectangular intake. The Alpine Fighter Collection in the New Zealand Fighter Pilot's Museum had the world's only Oscar in flying condition. It was one of the last Series 1s built, number 750 or so. The aircraft left the Alpine Fighter Collection in late 1999. The aircraft was sold to an undisclosed buyer, and exported from New Zealand.

    After WWII, Oscars (Mk III machines wore French colors in the Saigon area as counter-insurgency aircraft used for a short while against the Viet Minh until replacement by Supermarine Spitfires. The French had difficulty landing them due to lack of proper familiarization and several were wrecked. This was said to have amused the Japanese immensely as they considered it a piece of cake to handle in the air or on the ground. In China, Central Government Forces (KMT) had several Oscars but used them little due to the availability of fresh P-51s and other superior aircraft from the USA and Britain. But the Communist forces, known before 1949 as the Chinese Democratic Alliance Forces, had liberated a wing of late model Hayabusas at Shenyang, Liaoning Province in their occupation of the Northeast in 1945-47. Their air force experience began at that time under the guidance of a captured Major Kobayashi who set up a training school for pilots and technicians that became the Red forces' first aeronautical institute. They also received some of the assets of Manpi, Manchukoku Air Industries, and Japanese-built Jungmann trainers, which Soviet forces left for them. When the Chinese Civil War ignited in 1947 Kobayashi's personnel and the new Red Chinese Air Unit, mostly Oscars and Franks, saw some action and were almost used in the big push to cross the Yangzi River that finally defeated the Nanjing Central Government of Generalissimo Jiang Zhongzheng on the mainland. On October 1st, 1949, Major Kobayashi himself, in an Oscar with the PLA star and bar 8-1 insignia, himself flew the aerobatic display over Tiananmen Square as Mao Zedong proclaimed the birth of the Peoples Republic of China. An ironic footnote to the 8 year war waged by the Japanese to rid China of both Bolshevism and Jiang's independent (of Japan that is), neoclassical Chinese nationalism. In another case of demobilized Japanese aiding leftist guerillas, Oscars were also used in the Malaysian insurgency under supervision of Japanese soldiers and airmen who basically continued their war by siding with rebels against the return of British rule. And the Royal Thai Air Force May have used them well into the 1950s.

Nakajima Ki-43 (Oscar)
Wing span: 35 ft 7 in (10.86 m)
Length: 29 ft 4 in (8.93 m)
Height: 10 ft 9 in (3.27 m)
Empty: 3,821 lb (1,733 kg)
Max Gross: 5,850 lb (2,635 kg)
Maximum Speed: 320 mph (514 km/h)
Service Ceiling: 36,800 ft (11,216 m)
Range: 1,864 miles (3,000 km)
1,100 hp Nakajima Ha-105, 14-cylinder, radial, air cooled engine.
One 12.7 mm machine gun. One 7.7 mm machine gun.
Two 551 lb (250 kg) bombs.

FAOW, 1979, 1997
Maru Mekaniku Ki-43
Translated and adapted by Nathan Sturman

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Created March 28, 2007. Updated December 8, 2015.