Japan’s first indigenous combat aircraft produced since the end of World War II, the F-1 originated from a 1972 decision to develop a single-seat close air support fighter from the Mitsubishi T-2 supersonic trainer. The overall performance of the latter was such that virtually no aerodynamic modifica¬tions had to be made, the principal change from the T-2 to the F-1 being the fairing over the rear cockpit for a bombing computer, inertial navigation and radar warning systems, without changing the contours. Two T-2s were converted to a single-seat fighter variant and redesignated FST-2 Kai. The first flight of this prototype (59 5107) took place on 3 June 1975, a conversion of the third production T 2 trainer.
The two prototypes were modified T-2s with weapons systems equipment and test instrumentation in the rear cockpits. Powered by two 7,070 lb st / 3207kg with afterburning Ishikawajima-Harima TF40-IHI-801A (licence-built Rolls-Royce/Turbomeca Adour) turbofans, the F-1 was armed with a single 20mm JM61 multi-barrel cannon in the lower front fuselage and had provision for up to 2721kg of bombs or rockets on the fuselage centreline and four wing hardpoints. Normal armament comprised two ASM-1 air-to-surface missiles and two or four AIM-9 Sidewinder AAMs.
Its primary task in the Japanese Self Defense Force was anti-shipping with the 50km range ASM-1 anti-ship missile as its primary weapon. It is equipped with the J/AWG-12 radar which has two operating modes, air-to-air and air-to-surface, and is compatible with the ASM-1 missile. It has an air-to-air capability using the AIM-9 IR seeking missile, but because of its short range this capability is only limited.
The Air Self-Defence Force purchased 77 F-1s, and the first production example (70¬8201) of the Mitsubishi F 1 was flown on 16 June 1977. First deliveries of the initial 59 aircraft ordered began in 1977 to the 3rd Squadron of the JASDF’s 81st Air Wing were made on 26 September 1977, and in April 1978 the first F-1 entered JASDF (Japanese Self Defense Force) service. All were delivered by 1987.
70 were retrofitted during 1991-93 to enable them to remain in Air Self-Defence Force service until 1999-2000. The retrofit included installation of an advanced fire control system, provision of a stronger cockpit canopy and compatibility with the ASM-2 anti-shipping missile and XGCS homing bomb.
The F-1 was scheduled to be replaced by the F-2.
Mitsubishi F-1 Engines: two 32.49 kN (7,305 lb st) Ishikawajima-Harisma TF40-IHI-801 (license built Rolls-Royce/Turbomeca Adour Mk 801A) afterburning turbofans Wing span 7.88m (25 ft 10¼ in) Length 17.86m (58 ft 7 in) Height 4.39m (14 ft 5 in) Wing area, 228 sq ft (21,18 sq.m) Empty weight, 14,017 lb (6 358 kg) Max loaded weight, 30,146 lb (13 674 kg) Max speed, 1,056mph (Mach 1.6 / 1700 km/h) at 40,000 ft (12 190 m) Service ceiling 15240m (50,000 ft) Initial climb, 35,000 ft/ min (177,8 m/sec) Combat radius, 346 mls (556 km) Max range: 1100 km / 684 miles Armament: one JM61 Vulcan 20mm multi-barrel cannon with 750 rounds Hardpoints: 5 Bombload: 2721 kg (6,000 lb)
The T-2 was the first supersonic aircraft developed by the Japanese aircraft industry. It is a twin-engined two-seat jet trainer designed to meet the requirements of the JASDF. The first XT-2 prototype took to the air on 20 July 1971 and flew supersonically for the first time in level flight (Mach 1.03) during its 30th flight on 19 November 1971.
Armed with the 20mm Vulcan rotary cannon, production orders were placed for 92 T-2s: 28 T-2 advanced trainers, 62 T-2A combat trainers, and two as prototypes for the F-1 close-support fighter version. All of them retired from service by 1988.
Two T-2s were converted to a single-seat fighter variant and redesignated FS-T-2 Kai. The Mitsubishi FS-T2 Kai single seat close support fighter prototype (59 5107) was the first to fly on 3 June 1975, a conversion of the third production T 2 trainer. Designated F 1 in production form.
Mitsubishi T-2 29-5177 of JASDF ‘Blue Impulse’ team, Chitose, August 1982
A T-2 supersonic twin-turbofan advanced trainer modified to serve as a Control Configured Vehicle (CCV) testbed and distinguished by new horizontal canard and vertical control surfaces flew in August 1983. An extensive test programme undertaken by the JASDF/TRDI had achieved a total of 138 flights by March 1986, exploring all flight regimes including relaxed-stability and direct side force control.
Engines: 2 x Rolls Royce Turbomecca Adour turbofan, 22.8kN / 70 lb Wingspan: 7.9 m / 25 ft 11 in Length: 17.9 m / 58 ft 9 in Height: 4.5 m / 14 ft 9 in Wing area: 21.2 sq.m / 228.19 sq ft Max take-off weight: 9650 kg / 21275 lb Empty weight: 6200 kg / 13669 lb Max. speed: M1.6 Ceiling: 15250 m / 50050 ft Range w/max.fuel: 2870 km / 1783 miles Armament: 1 x 20mm cannon, 8-12 bombs, 2-4 missiles Crew: 2
To take the place of the Mitsubishi Ki-21 ‘Sally’ and the Nakajima Ki-49 ‘Helen’, the Air Office (Koku Hombu) issued specifications for a new bomber to the Mitsubishi concern in November 1940. The work was led by Chief Engineer Ozawa on an aircraft based on the beautiful Japanese lines and powered by the new generation of Ha-100 double-row 18- cylinder radial engines.
Three prototypes of the Ki-67-I were completed between December 1942 and March 1943, the first making its initial flight on 27 December 1942. The Ki-67-I proved to be fast (though not as fast as originally specified), and extremely manoeuvrable with loops and barrel-rolls being carried out with ease in an unloaded configuration.
Although adopted for service as the Army Type 4 Heavy Bomber, such was the promise of the Ki-67-I that even the Imperial Japanese Navy was impressed, and made early representations to Mitsubishi. On 5 January 1943 Mitsubishi received an order to convert 100 Ki-49s as torpedo-bombers, with internal racks capable of handling the standard 450mm Navy Type 91 Model II aerial torpedo. These saw service with the 762nd Kokutai (air group) from the autumn of 1944 onwards. The Ki-67- I was issued in small numbers to the 7th, 14th, 16th, 61st, 62nd, 74th, 98th and 110th Hikosentais (air regiments) and saw limited action over China, Biak and Sansapor in north western New Guinea, and Sumatra in the summer of 1944.
Comparitively few Ki.67-1a were completed before being superceded by the Ki.677-1b, which continued in production to the end of the war.
Ki.67-1a
Three other manufacturers, Kawasaki, Nippon and Rikugun, were in the production team, but only completed just over 100 aircraft between them.
The type was recognized as such for the first time by the Allies in October 1944, code named ‘Peggy”, during the US 3rd Fleet’s attacks on Formosa and the Ryukyus where the Hiryu served in the 8th Hikoshidan (air division) based on Formosa under navy control. Thereafter Ki-67-Is were encountered over the Philippines, off Iwo Jima, in the strikes on the US 20th Air Force’s bases on Saipan and Tinian, and in the Okinawa campaign where it was used as a suicide aircraft.
For suicide missions the JAAF used modified Peggys known as the Ki-61-I KAI with armament removed and a solid nose packed with explosive. Only two of the more powerful Ki-67-II variant were made, production of army and navy Ki-67-Is amounting to 696.
Ki-67 Engines: 2 x Mitsubishi HA-104 18-cyl radial, 1425kW Max take-off weight: 13765 kg / 30347 lb Empty weight: 8649 kg / 19068 lb Wingspan: 22.5 m / 73 ft 10 in Length: 18.7 m / 61 ft 4 in Height: 7.7 m / 25 ft 3 in Wing area: 65.85 sq.m / 708.80 sq ft Max. speed: 537 km/h / 334 mph Cruise speed: 400 km/h / 249 mph Ceiling: 9470 m / 31050 ft Range w/max.fuel: 3800 km / 2361 miles Range w/max.payload: 2800 km / 1740 miles Armament: 1 x 20mm cannon, 4 x 12.7mm machine-guns, 500-800kg of bombs
Ki-67-Ib Engines: 2 x Mitsubishi Ha-104, 1900 hp Wing Span: 22.50m / 73 ft 9.75 in Length: 18.70m / 61 ft 4.25 in Height: 7.70m / 15 ft 9 in Wing Area: 65.85sq.m Empty Weight: 8650kg / 19,069 lb Max.Weight: 13765kg / 30,346 lb Max speed: 537 km/h / 334 mph at 19,980 ft Service ceiling: 9470m / 31,070 ft Range: 2800km / 2360 mi Armament: 1 x 20mm, 4 x mg12.7mm Bombload: 800kg / 1760 lb Crew: 6-8
To meet an Imperial Japanese Army specification of December 1937 for a two seat ground-attack aircraft, which it was suggested could be a development of the Ki-30 light bomber, Mitsubishi produced two prototypes under the designation Mitsubishi Ki-51.
The Ki 51 was a cantilever low wing monoplane, with a ‘trousered’ and spatted non retractable main landing gear and a fixed tail wheel. The powerplant for both prototype and production aircraft was a single 940 hp Mitsubishi Ha 26 II 14 cylinder air cooled radial engine, driving a three blade variable pitch metal propeller. The greenhouse canopy was shorter than that on the Ki 30, bringing the two man crew closer together, and a degree of armour protection was provided for the occupants and the engine. The Ki 51 differed from the Ki 30 in having no internal bomb bay, the normal 200-kg (440 lb) weapon load being carried externally. Overall construction was of metal except for the control surfaces, which were fabric covered.
Two prototypes, designated Ki 51, were completed in June and August 1939, followed immediately by a pre series batch of 11 more, all completed by the end of that year. They differed from the prototypes by incorporating a number of modifications, including the introduction of fixed leading-edge slots to improve slow-speed handling and armour plate beneath the engine and crew positions.
After a virtually problem free flight test programme, and only a few minor modifica¬tions, the Ki 51 entered production in January 1940 as the Army Type 99 Assault Aircraft. From then until March 1944 Mit¬subishi’s Nagoya factory manufactured a total of 1459. Four months later a second production line was established by Tachikawa, which had completed a further 913 by July 1945. Standard armament at first consisted of three 7.7 mm (0.303 in) Type 89 machine guns, one in each wing and one in a movable mounting in the rear cockpit. On later aircraft, the wing mounted pair were exchanged for Type 1 guns of 12.7 mm (0.5¬in) calibre, and the aircraft’s range was increased by installing a 68 litre (15 Imp gal) fuel tank in each wing leading edge. The Ki¬-51 served with at least eight Sentais (groups) and a dozen or more independent squadrons of the Japanese army air force, from 1940 until the end of the Second World War. It established a reputation for being reliable and capable of surviving considerable battle dam¬age, which made it popular with its crews. It was given the Pacific codename Sonia by the Allies. Adapted, inevitably, for the kamikaze role towards the end of the war, it was flown as a single seater, carrying a 250 kg (550 lb) bomb beneath the fuselage.
In addition to the standard production aircraft, there were attempts to develop dedicated reconnaissance versions, initially by the conversion of one Ki-51 service trials aircraft which had the rear cockpit redesigned to accommodate reconnaissance cameras. Test and evaluation of this aircraft, redesignated Ki-51a, brought a realization that the standard Ki-51 could be modified to have provisions for the installation of reconnaissance cameras, and this change was made on the production line.
Three prototypes were completed at Tachikawa of the Ki 71 (codenamed Edna), an improved, retractable gear version with a 1500 hp / 1119kW Mitsubishi Ha-112-11 engine and two 20mm wing cannon, but no production orders for this type were placed.
Allocated the Allied codename ‘Sonia’, the Ki-51 was used initially in operations against China, and was deployed against the Allies until the end of the Pacific war. In more intensely contested areas the fairly slow Ki-51s were easy prey for Allied fighters, but in secondary theatres, where an ability to operate from rough and short fields was valuable, these aircraft gave essential close support in countless operations. In the closing stages of the war they were used in kamikaze attacks.
Ki-51 Engine: 940 hp / 705kW Mitsubishi Ha 26 II radial Prop: three blade variable pitch metal Wingspan: 12.1 m / 39 ft 8 in Length: 9.21 m / 30 ft 3 in Height: 2.73 m / 8 ft 11 in Wing area: 24.02 sq.m / 258.55 sq ft Max take-off weight: 2798-2920 kg / 6169 – 6438 lb Empty weight: 1873 kg / 4129 lb Max. speed: 424 km/h / 263 mph Ceiling: 8270 m / 27150 ft Range: 1060 km / 659 miles Crew: 2 Armament: 3 x 7.7mm machine-guns, 200-300kg of bombs
Tachikawa Ki-71 Engine: 1500 hp / 1119kW Mitsubishi Ha-112-11 Undercarriage: retractable Armament: two 20mm wing cannon
The Mitsubishi Ki-46 was designed to meet an Imperial Japanese Army requirement of 1937 for a higher performance reconnaissance aircraft to supersede the Ki-15. The specification called for an endurance of six hours at 250mph (400 km/h), between 13,500 and 20,000 ft (4,000 and 6,000m) and a maximum speed of 375mph (604km/h) at 13,500 ft (4,000m). The man responsible for the design was Tomio Kubo, who was assisted by the Aeronautical Research Institute of the University of Tokyo.
Work on the design started in December 1937, as a cantilever low-wing monoplane with retractable tailwheel landing gear, powered by two 900 hp / 671kW Mitsubishi Ha-26 radial engines. Kubo selected a small diameter fuselage with the main fuel tank located between pilot and observer, and thin section wings.
The two-seat Ki-46 prototype was flown (by Major Fujita) for the first time in late November 1939 from Kagamigahara in Gifu Prefecture, north of Nagoya. Early testing showed that maximum speed of the Ki-46 was some 10% below specification (540 km/h / 335 mph) at 4000 m / 13,000 ft), but as its speed and overall performance was better than in-service army and navy aircraft the type was ordered into production as the Army Type 100 Command Reconnaissance Plane Model 1 (Ki-46-l), later allocated the Allied codename ‘Dinah’.
The entire Model 1 production (34 were built between 1939 40) plus the prototype were delivered to the Shimshizu flying school and to a special experimental reconnaissance unit. The aircraft was known as the Shintei in Japanese service, but was soon better known to the allies under its simplified identification name, the Dinah.
The Ki-46-1 series was soon replaced by the Ki-46II, which utilised the more powerful Ha102 engines, fitted with two-speed supercharger and rated at 1,080 hp each. The increase in available horsepower meant that the performance of the II improved, maximum speed rose to 375 mph (604 kph) at 19,030 ft (5,800 m). The transition to the new series was not without its problems, vapour locks were experienced and it was only after extensive research that the cause was found. Relocation of the fuel lines around the engines and a change from 87 to 92-octane fuel seemed to cure it. Poor aileron and rudder response, overheating of the oil and an unreliable oxygen system that to crew anoxia, were all problems which had to be overcome. Another problem involved the undercarriage, due to the aircraft’s high rate of sink it was quite a common occurrence for the undercarriage to collapse on landing. Although stronger auxiliary rear struts were fitted this problem was to persist throughout the Ki-46’s operational life.
The first Model 2 appeared in March 1941, the airframe was identical with the Model 1 and production soon gathered momentum. The Type 100 was delivered from July 1941 onwards to the 18th, 50th, 51st, 70th, 74th, 76th and 81st Independent Chutais (squadrons) based in China and Manchuria. Chinese air opposition was poor and the escape capability of Ki 46 such that the sole defensive armament, a single 7.7 mrn (0.303 in) Type 89 machine gun on a flexible mounting operated by the observer, was seldom used in action.
During October 1941 Ki 46s based in French Indo China reconnoitred the Japanese army’s planned landing zones for the December invasion of Malaya. From December 1941 onwards, Ki 46s were deployed in small detachments in every army zone of operations, enjoying considerable success and remaining virtually unmolested for the first year of fighting. Such was the esteem in which the type was held that the Luftwaffe attempted to arrange licence production, and the army’s greatest rival, the navy, managed to acquire a few for its own use.
As the losses suffered by the Ki-46II units increased the Koku Hombu, in May 1942, they instructed Mitsubishi to upgrade the Ki-46-II. This was achieved with the installation of two Mitsubishi Ha 112-II engines, rated at 1,500hp each, this boosted the top speed to 404 mph (650 km/h) and increased the range to 2,485 miles and endurance by an hour. The new design was designated the Ki-46-III and with it came a whole new shape. Gone was the stepped canopy of the II series and in came a completely aerodynamic nose, with the canopy glazing extending right to the front of the aircraft in a smooth slope. The reason for the re-designed front was a simple, not just one born of aerodynamic necessity. The new engines required more fuel and the thin wing adopted in the original design allowed no room for fuel cells, it was therefore decided to fit an additional tank in front of the pilot. This tank held 52 Imp Gal (220 litres), provision was also made for the fitment of a ventral drop tank, holding 101.2 Imp Gal (460 litres). The undercarriage was beefed up and the provision for a single flexible machine gun in the rear cockpit was dispensed with.
As supply of the III series increased, some II’s were converted into three seat radio navigation trainers, designated the Ki46-II Kai, they operated with the Shimoshizu Rikugun Hikogakuko (Shimoshizu Army Flying School).
609 Ki-46-III were built, a small number being converted later as Ki-46-III KAI fighter interceptors and Ki-46IIIb ground-attack aircraft.
The Ki-46-II and the Ki46-IIKai (Kai=KAIZO “Modified”) trainer were the main production version of the Ki-46 design, with 1,093 being built.
In June 1943, the Rikugun Kokugijutsu Kenkyujo, or Army Aerotechnical Research Institute, began to study the adaptation of the Ki-46-III reconnaissance aircraft for the high-altitude interceptor fighter role. Development was actively pursued from May 1944 as the Ki-46-III KAI, or Army Type 100 Air Defence Fighter, and the Army Air Arsenal at Tachikawa instituted a conversion programme.
The nose was redesigned a new stepped cockpit canopy, and to accommodate two 20-mm Ho-5 cannon and the top centre fuselage fuel tank was removed to provide space for a Ho-203 37-mm cannon firing forward and upward at an angle of 30 deg. The two Mitsubishi Ha-112-lI engines rated at 1,500 hp for take-off were retained, and the first Ki-46-IIl KAI two-seat interceptor was completed by Tachikawa Dai-lchi Rikugun Kokushok and flown in October 1944, deliveries to operational units commencing during November. Operational results were disappointing owing to the poor climb rate of this type, but the conversion programme was continued at Tachikawa until March 1945, a substantial number being delivered. One unit was the 16th Dokuritsu, Hikotai, which operated in the latter months of the war.
With more powerful 1500-hp Mitsubishi Ha 112 11 engines and increased range, thanks to enlarged internal tankage and the introduction of a 460 litre (101 Imp gal) ventral drop tank, Model 3 showed a 26 km/h (16 mph) improvement in top speed over Model 2 and achieved a maximum range of 4000 km (2500 miles). External appearance was greatly changed by the new canopy over the pilot’s cockpit, without the conventional step between the nose and top of fuselage which had characterized the earlier versions. Performance was so good that defensive armament was dispensed with. Production at Mitsubishi’s Nagoya factory was hindered by earthquake damage in December 1944, and a further 100 of the type were built at Toyama.
Late production Ki-46-III’s coming from both plants were fitted with individual exhaust stacks providing some thrust augmentation, which increased their speed and range slightly.
Operational trainer modifications of the Model 2 serving with the specialist Shimshizu flying school had a third, stepped up cockpit fitted immediately behind the pilot’s seat.
Ki.46-IIIA
A few Ki 46 IIIb assault aircraft, devel¬oped from the intercepter, were built, and four Ki 46 IV high altitude prototypes during 1943 & 44, pow¬ered by 1,100 hp / 1119kW (at 33,465 ft / 10,200 m) Mitsubishi Ha 112 Ru supercharged engines, were tested from February 1944 onwards. Difficulties with the superchargers prevented production of the proposed reconnaissance and fighter versions. Total production of the Ki 46 in all variants was 1742 of which 902 were the III series, all built by Mitsubishi. All were initially manufactured by Mitsubishi at their Nagoya plant, but when this was damaged by an earthquake in December 1944, as well as being pounded by the B-29’s of the US Air Force, production was transferred to their new plant at Toyama. Only about one hundred aircraft came out of this plant by wars end.
Production: 34 Ki-46 prototypes and Ki-46-I production aircraft (1939-40) 1,093 Ki-46-II production aircraft (1940-44) 2 Ki-46-III prototypes (1942) 609 Ki-46-III production aircraft, inc fighter conversions (1942-45) 4 Ki-46-IV prototypes (1943-44)
Ki 46 I Engines: 2 x 900 hp Army Type 99 Model 1 Mitsubishi Ha-26-1 radials Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length: 36ft 1 1/16 in (11.0m) Empty weight: 7,449 lb (3,379 kg) Loaded weight: 10,631 lb (4,822 kg) Max speed: 335.5 mph at 13,350 ft Range: 1,305 Miles (2,100 km) Armament: One 7.7 mm Type 89 rear-firing machine-gun
Ki 46 II Engines: 2 x 1,050 hp Army Type 1 Mitsubishi Ha102 Wingspan: 48 ft 2.75 in (14.7m) Length: 36ft 1 1/16 in (11.0m) Height: 12 ft 8.75 in (3.88m) Empty weight: 7,194 lb (3263 kg) Loaded weight: 11,133 lb (5,050 kg) Maximum speed: 604 km/h (375 mph) at 19,000 ft Max speed: 375 mph at 19,030 ft Service ceiling: 35,170 ft Range: 1,537 Miles (2,474 km) Crew: 2 Armament: One 7.7 mm Type 89 rear-firing machine-gun
Ki 46 II Kai Engines: 2 x 1,050 hp Army Type 1 Mitsubishi Ha102 radials Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length: 36ft 1 1/16 in (11.0m) Armament: One 7.7 mm Type 89 rear-firing machine-gun
Ki-46-III Engines: 2 x Army Type 4 Mitsubishi Ha-112-II radials, 1125kW / 1,500 hp Max take-off weight: 5722-6500 kg / 12615 – 14330 lb Empty weight: 8,446 lb (3,831 kg) Loaded weight: 12,619 lb (5,722 kg) Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length: 36ft 1 1/16 in (11.0m) Wing area: 32.0 sq.m / 344.44 sq ft Max. speed: 630 km/h / 391 mph at 19,685 ft Ceiling: 10500 m / 34450 ft Range w/max.fuel: 4000 km / 2486 miles Crew: 2
Ki-46IIIa Engines: 2 x Army Type 4 Mitsubishi Ha-112-II radials, 1125kW / 1,500 hp Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length: 36ft 1 1/16 in (11.0m) Empty weight: 8,446 lb (3,831 kg) Loaded weight: 12,619 lb (5,722 kg) Max speed: 391 mph at 19,685 ft Range: 2,485 Miles (4,000 km)
Ki-46IIIb Engines: 2 x Army Type 4 Mitsubishi Ha-112-II radials, 1125kW / 1,500 hp Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length: 36ft 1 1/16 in (11.0m) Empty weight: 8,446 lb (3,831 kg) Loaded weight: 12,619 lb (5,722 kg) Max speed: 391 mph at 19,685 ft Range: 2,485 Miles (4,000 km)
Ki-46IIIc Engines: 2 x Army Type 4 Mitsubishi Ha-112-II radials, 1125kW / 1,500 hp Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length: 36ft 1 1/16 in (11.0m) Empty weight: 8,446 lb (3,831 kg) Loaded weight: 12,619 lb (5,722 kg) Max speed: 391 mph at 19,685 ft Range: 2,485 Miles (4,000 km)
Ki-46-III KAI Engines: 2 x Army Type 4 Mitsubishi Ha-112-II radials, 1125kW / 1,500 hp Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length, 37 ft 8¼ in (11,48 m) Wing area, 344.44 sq ft (32,00 sq.m) Max speed, 391 mph (630 km/h) at 19,685 ft (6 000 m) Range, 1,243 mls (2 000 km) plus one hour combat Time to 26,250 ft (8 000 m), 19 min. Empty weight, 8,446 lb (3 831 kg) Loaded weight. 13,730 lb (6 228 kg) Armament: One 37 mm Ho-203 cannon, two 20 mm Ho-5 cannons
Ki-46-IV Engines: 2 x 1,500 hp Mitsubishi Ha-112-II Ru radials Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length: 36ft 1 1/16 in (11.0m)
Ki-46-IVa Engines: 2 x 1,500 hp Mitsubishi Ha-112-II Ru radials Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length: 36ft 1 1/16 in (11.0m) Empty weight: 8,840 lb (4,010 kg) Loaded weight: 13,007 lb (5,900 kg) Max speed: 391 mph at 19,685 ft Range: 2,485 Miles (4,000 km)
Ki-46-IVb Wingspan: 48 ft 2.75 in (14.7m) Height: 12 ft 8.75 in (3.88m) Length: 36ft 1 1/16 in (11.0m)
In May 1936 the Imperial Japanese Army issued its specification for a light bomber required to supersede the Mitsubishi Ki-2 and Kawasaki Ki-3 then in service. The Mitsubishi Ki-30 prototype that resulted was of cantilever mid-wing monoplane configuration with fixed tailwheel landing gear, the main units faired and spatted, and powered by a 850 hp / 615kW Mitsubishi Ha-6 radial engine. The engine drove a three bladed variable pitch metal propeller. The Ki 30’s two man crew were housed beneath a long raised glazed canopy. Armament comprised a wing mounted forward-firing 7.7 mm (0.303 in) Type 89 machine gun with a similar weapon on a flexible mounting in the rear cockpit operated by the observer. The normal bombload of 300 kg (660 lb) was carried internally in the bomb bay. The Ki 30 was characterized by its fixed undercarriage with single cantilever strut main units fitted with open sided wheel spats.
The first prototype made its initial flight at the army’s Kagamigahara experimental airfield on February 28, 1937. The army specification had called for a maximum speed of 400 km/h (248 mph) and this was easily exceeded. All other requirements were met except that the weight was slightly more than the specified maximum of 3300 kg (7275 lb). The second prototype had a more powerful Nakajima Ha-5 KAI radial engine. This aircraft showed some slight improvement in performance but, in any case, exceeded the army’s original specification, so there was no hesitation in ordering 16 service trials aircraft. These were delivered in January 1938 and, two months later, the Ki-30 was ordered into production.
Production at Mitsubishi’s Nagoya plant started at the beginning of 1938, utilizing an alternative engine, the 960hp Nakajima Ha 5 Kai. Mitsubishi built 636 aircraft up to April 1940, supplemented by 68 completed at the Tachikawa army arsenal workshops between 1939 1941.
In service with six Sentais (groups) and several independent Chutais (squadrons) as the Army Type 97 Light Bomber, first used operationally in China during 1938.
A number were.supplied to Thailand who used them against the French in Indo China during early 1941. When war was declared on Britain and the United States, Ki 30 units operated in the Philippines, but were from then on gradually transferred to training schools from where a number flew kamikaze missions in the summer of 1945. The Allied codename ‘Ann’ was allocated to the Ki-30, but few were seen operationally after the opening phases of the war.
A total of 704 had been built when production ended in 1941, 68 manufactured by the First Army Air Arsenal at Tachikawa.
Ki-30 Engine: 1 x Mitsubisi Ha-6, 710kW Max take-off weight: 3322 kg / 7324 lb Empty weight: 2230 kg / 4916 lb Wingspan: 14.55 m / 47 ft 9 in Length: 10.34 m / 33 ft 11 in Height: 3.65 m / 11 ft 12 in Wing area: 30.58 sq.m / 329.16 sq ft Max. speed: 432 km/h / 268 mph Cruise speed: 380 km/h / 236 mph Ceiling: 8570 m / 28100 ft Range: 1700 km / 1056 miles Crew: 2 Armament: 2 x 7.7mm machine-guns, 300-450kg of bombs
The Mitsubishi F1M development started in 1934, and first flown in June 1936. The F1M1 embodied all the efforts of its designers to achieve an exceptionally clean aerodynamic shape, including low-drag float mountings, single interplane struts and all-metal construction, only the control surfaces being fabric-covered. The early aircraft displayed poor water handling and a lack of in-flight directional stability but after fairly extensive alterations the production F1M2 emerged as a thoroughly efficient aircraft, acceptable in all respects. Initial production by Mitsubishi, begun in 1938, amounted to 524 aircraft before it was transferred to the 21st Naval Air Arsenal (Dai-Nijuichi Kaigun Kokusho) at Sasebo, where a further 590 were built.
The F1M2 equipped all but one of the K-Maru (6,900-ton) and S-Maru (7,200/8,300-ton) classes of converted merchant seaplane tenders, as well as numerous battleships and cruisers of the Imperial Japanese Navy.
Codenamed ‘Pete’ by the Allies, F1M2s were present at the Battle of Midway, two aircraft being launched from the battleship Kirishima (but being lost when the Japanese scuttled the crippled ship at the end of the Battle of the Solomons). The battleships Musashi and Yamato each carried several ‘Petes’ to spot for their 460mm main gun armament at the time of the Marianas battles, but none was used in earnest. The Musashi succumbed to American bombs and torpedoes in the Sibuyan Sea; the Yamato followed her to the bottom on 7 April 1945. ‘Pete’ seaplanes were widely used throughout the Pacific war, accompanying every seaborne landing by Japanese forces, providing gunnery spotting during preliminary bombardment by supporting warships and subsequently serving as covering fighters (and even dive-bombers) once the assault forces were ashore. It was also flown on convoy escort duties with the many supply convoys sailed by the Japanese during the mid-war period.
In the last stages of the war, the type was committed to the unequal task of defending the Japanese homeland from the devastating American raids, serving alongside ‘Rex’ and ‘Rufe’ seaplane fighters with the Otsu Kokutai in 1945.
F1M2 Crew: 2 Engine: 1 x Mitsubishi Tsuisei-13, 655kW Max take-off weight: 2550 kg / 5622 lb Empty weight: 1928 kg / 4251 lb Wingspan: 11 m / 36 ft 1 in Length: 9.5 m / 31 ft 2 in Height: 4 m / 13 ft 1 in Wing area: 29.54 sq.m / 317.97 sq ft Max. speed: 365 km/h / 227 mph Ceiling: 9440 m / 30950 ft Range: 730 km / 454 miles Armament: 3 x 7.7mm machine-guns, 120kg of bombs
The Mitsubishi Ki-21 (Army Type 97 Heavy Bomber) was produced by engineers Nakata and Ozawa in response to an operational specification issued by the Air Headquarters (Daihonei) of the JAAF on 15 February 1936. The original specification, issued in February 1936, had required an aircraft with an endurance of over five hours at an average cruising speed of 300 km/h (186 mph), able to climb to 3000 m (9840 ft) in eight minutes and reach a maximum 400 km/h (248 mph) at that height. Normal crew was to be four, with provision for two more gunners on missions where extensive air opposition was anticipated. Maximum bombload for short range missions was to be 1000 kg (2200 lb). Early production aircraft in fact met or exceeded all these criteria.
In its definitive form the Ki 21 was a midwing monoplane of all metal semi-monocoque construction, and the smoothly contoured fuselage was oval in section. It had a single fin and rudder, and the main under-carriage legs retracted forward into the two engine nacelles.
The first of eight prototypes and service trial aircraft flew on December 18, 1936. It had a square glassed in nose, dorsal gun turret and a ventral step for a lower defensive gun. Later prototypes adopted a long dorsal greenhouse accommodating the gunner’s position, a well contoured hemispherical glassed in nose and a smooth lower fuselage line which eliminated the ventral step. To improve directional stability the fin and rud¬der were redesigned and increased in area. The first prototype had two Mitsubishi Ha 6 825 hp radial engines, while the remaining prototypes and early production machines had 850 hp Nakajima Ha 5 Kais.
Before going into production the Ki 21 had survived a competition with its rival the Nakajima Ki 19. As a consolation a contract was awarded by the Koku Hombu (the army air headquarters) not only to Mitsubishi (432 Model Is built) but also to Nakajima (351 Model Is).
A year late in entering service, some of its technology, compared with that of contemporary foreign aircraft, was not as advanced as the designers Nakata and Ozawa had hoped. The gap left by the delay in delivery of Ki 21s had to be filled by importing Fiat B.R.20 bombers. The first production model being the Mitsubishi Ki-21-Ia (Army Type 97 Model 1A). Because of production bottlenecks it was not until the end of 1939 that Ki-21-la bombers equipped the first JAAF unit, the 60th Hikosentai (air regiment) based in China, the next unit to be equipped was the 61st Sentai.
Early lessons learned over China demonstrated lack of firepower and protection, and the Ki-21-Ib and Ki-21-Ic subvariants had extra armour, additional 7.7mm Type 89 machine-guns, more fuel and larger bomb-bays. The engines were 634kW Nakajima Ha-5 KAI radials.
By the time of the outbreak of war in December 1941, the majority of the Mitsubishi Ki-21-Ia, Ki-21-Ib and Ki-21-Ic bombers had been relegated to second-line duties, or to service as operational bomber trainers. Most army front line bomber units were equipped with the Model 2 version of Ki 21, powered by two 1450 hp / 1119kW Mitsubishi Ha 101 14 cylinder radials driving constant speed three bladed metal propellers, unlike the Ha 5 Kai radials of the earlier version which had variable pitch propellers. The larger and more powerful Ha 101s required larger nacelles, and these completely enclosed the retracted landing wheels in the earlier machines, the wheels were left partly exposed.
Production models in service in 1941 were the Ki-21-IIa (Army Type 97 Heavy Bomber Model 2A), and the Ki-21-IIb which had a pedal-operated dorsal turret with one 12.7mm Type 1 heavy machine gun. Three sentais remained in Japan, Korea and in Manchuria when the Japanese high command went to war in South East Asia. For operations over the Philippines the JAAF’s 5th Air Group, based in Formosa, mustered the 14th and 62nd Hikosentais; these went into action early on the morning of 8 December 1941 striking at Aparri, Tuguegarao, Vigan and other targets in Luzon. Mitsubishi Ki-21s of the 3rd Air Group, based in French Indo-China, were earmarked for bombing strikes against Siam (Thailand) and Malaya: units were the 12th, 60th and 98th Hikosentais. These smashed RAF and RAAF facilities at Alor Star, Sungei Patani and Butterworth, being escorted by Nakajima Ki-27 and Ki-43 fighters. Only over Rangoon over December 1941 and January 1942 did the Ki-21s, codenamed ‘Sally’, suffer heavy casualties.
At its peak the Ki 21 was supplied to 11 first line Sentais and played a considerable part in the Pacific air war. Towards the end of its career lack of Ki 49 and Ki 67 replacements forced the retention of the Ki¬-21 in the first line when it was obsolete and suffering heavy losses. It took part in a number of outstanding actions, perhaps the most notable of which was the suicide mission by nine Model 2s of the 3rd Dokuritsu Hikotai (independent air wing). These were to land on the US occupied airfield at Yontan on Okinawa in the summer of 1945 to launch commando style attacks on airfield installations and aircraft. Only one aircraft survived to deliver its troops, but considerable damage was inflicted before they were wiped out.
The original Ki 21 defensive armament of single flexibly mounted 7.7 mm (0.303 in) Type 89 machine guns mounted in nose, dorsal and ventral positions proved barely adequate even for operations against the poorly equipped Chinese air force, and the Ki 21 Ib had an additional gun in a remotely operated tail stinger position plus another which could be fired from lateral positions on either side of the fuselage. The Ki 21 Ic and IIa had two beam guns while the Ki 21 IIb (688 of which were built between 1942 1944) had a remotely controlled tail stinger position for a 7.7 mm (0.303 in) machine gun, and the dorsal greenhouse replaced by a large conical turret mounting a single 12.7 mm (0.54in) Type 1 machine gun. This latter change greatly altered the appearance of the Ki 21 IIb and for a period it was thought by the Allies to be a new bomber type and given a different codename, Gwen, which was soon dropped when the new version was properly identified.
The bombload of all Ki 21 versions remained the same: a normal load of 750 kg (1653 lb) and a maximum of 1000 kg (2205 lb). The maximum range was 2700 km (1680 miles).
Some Ki 21 Ia bombers were modified during 1940 and put into service as MC 21 freight transports. Formally they passed into civil use as they were operated by the Dai Nihon Koku KK (Greater Japan Airlines) on routes between Japan, China and Manchuria, but all these flights were in fact military contract work, carrying army supplies (or personnel). Although all armament and other equipment appropriate to the bombing role had been removed, the aircraft were externally identical to the bombers, until a number were modified by the fitting of a ‘solid’ nose.
The Ki.21 was coded ‘Jane’ after Gen. MacArthur’s wife but when this came to his attention at the General’s request the code was changed to ‘Sally’,
Code named Sally, a modified model with a smooth dorsal line and a gun turret in place of the ‘greenhouse’ led spotters to believe a new type was entering service. The name ‘Gwen’ was assigned, but soon dropped in favour of ‘Sally 3’ when it was identified as a model variation.
Production of the Ki 21 ceased in September 1944, with the 2064th aircraft.
Ki-21 (Army Type 97 Heavy Bomber) prototype Engines: 2 x Mitsubishi Ha 6 825 hp radial or 850 hp Nakajima Ha 5 Kais. Propellers: variable ¬pitch Span: 22.5m (73ft l0in) Length: 16m (52ft 6in) Height: 4.35 m / 14 ft 3 in Wing area: 69.6 sq.m / 749.17 sq ft
Ki-21-Ia (Army Type 97 Model 1A) Engines: 2 x 850 hp Nakajima Ha 5 Kais. Propellers: variable ¬pitch Span: 22.5m (73ft l0in) Length: 16m (52ft 6in) Height: 4.35 m / 14 ft 3 in Wing area: 69.6 sq.m / 749.17 sq ft Gross weight: 7916 kg (17452 lb) Empty weight: 4691 kg / 10342 lb Maximum speed: 432 km/h (268 mph) at 4000 m (13,125 ft) Ceiling: 8600 m / 28200 ft Range w/max.fuel: 2700 km / 1678 miles Range w/max.payload: 1500 km / 932 miles Crew: 5 Armament: 3 x 7.7mm (0.303 in) Type 89 machine-guns Bombload: 750 kg (1653 lb) – 1000 kg (2205 lb)
Ki-21-Ib Engines: 2 x 634kW Nakajima Ha-5 KAI radials. Propellers: variable ¬pitch Span: 22.5m (73ft l0in) Length: 16m (52ft 6in) Height: 4.35 m / 14 ft 3 in Wing area: 69.6 sq.m / 749.17 sq ft Maximum range: 2700 km (1680 miles) Armament: 4 x 7.7mm (0.303 in) Type 89 machine-guns Bombload: 750 kg (1653 lb) – 1000 kg (2205 lb)
Ki-21-Ic Engines: 2 x 634kW Nakajima Ha-5 KAI radials. Propellers: variable ¬pitch Span: 22.5m (73ft l0in) Length: 16m (52ft 6in) Height: 4.35 m / 14 ft 3 in Wing area: 69.6 sq.m / 749.17 sq ft Maximum range: 2700 km (1680 miles) Armament: 4 x 7.7mm (0.303 in) Type 89 machine-guns Bombload: 750 kg (1653 lb) – 1000 kg (2205 lb)
Ki 21-II Engines: 2 x 1450 hp / 1119kW Mitsubishi Ha 101 14 cylinder radials Props: constant speed three bladed metal Span: 22.5m (73ft l0in) Length: 16m (52ft 6in) Height: 4.35 m / 14 ft 3 in Wing area: 69.6 sq.m / 749.17 sq ft Maximum range: 2700 km (1680 miles) Armament: 4 x 7.7mm (0.303 in) Type 89 machine-guns Bombload: 750 kg (1653 lb) – 1000 kg (2205 lb)
Ki-21-IIa (Army Type 97 Heavy Bomber Model 2A), Engines: 2 x 1450 hp / 1119kW Mitsubishi Ha 101 14 cylinder radials Props: constant speed three bladed metal Span: 22.5m (73ft l0in) Length: 16m (52ft 6in) Height: 4.35 m / 14 ft 3 in Wing area: 69.6 sq.m / 749.17 sq ft Maximum range: 2700 km (1680 miles) Armament: 4 x 7.7mm (0.303 in) Type 89 machine-guns Bombload: 750 kg (1653 lb) – 1000 kg (2205 lb)
Ki-21-IIb Engines: 2 x 1450 hp / 1119kW Mitsubishi Ha 101 14 cylinder radials Props: constant speed three bladed metal Span: 22.5m (73ft l0in) Length: 16m (52ft 6in) Height: 4.35 m / 14 ft 3 in Wing area: 69.6 sq.m / 749.17 sq ft Empty weight: 13,382 lb Gross weight: 9710 kg (21407 lb) Maximum speed: 486 km/h (302 mph) at 4720 m (15,485 ft). Maximum range: 2700 km (1680 miles) Armament: 4 x 7.7mm (0.303 in) Type 89 machine-guns, 1 x 12.7mm Type 1 heavy machine gun. Bombload: 750 kg (1653 lb) – 1000 kg (2205 lb) Crew: 7
In July 1935 the Imperial Japanese Army drew up its specification for a new two-seat reconnaissance aircraft, and Mitsubishi responded with a can¬tilever low-wing monoplane, the Mit¬subishi Ki-15.
The Ki 15, or Army Type 97 Command Reconnaissance Aircraft, owed its inception to Lieutenant¬ Colonel Yuzo Fujita of the army air force, who collaborated closely in its design with the Mitsubishi engineers Kono, Kubo and Mizumo. It was among the first strategic reconnaissance aircraft to be adopted by any air force. Two prototypes, one military and one civil, were completed, the former making the type’s first flight in May 1936.
Shortly afterwards, the Asahi Shimbun newspaper group purchased the second prototype, which as the Karigane I (wild goose) made a historic flight from Tachikawa to Croydon, a distance of 15 356 km. (9542 miles) in April 1937 in a flying time of approximately 51¼ hours.
Service testing was completed without difficulty and the type was ordered into production under the official designation Army Type 97 Command Reconnaissance Plane Model 1. In May 1937, a year after the first flight, delivery of production aircraft to the army began.
The military Ki 15 was a clean, low wing monoplane, with a 640 hp Nakajima Ha 8 nine cylinder radial engine and a ‘trousered’ and spatted main undercarriage. The pilot and radio operator/observer (who also doubled up as the gunner) sat in tandem cockpits under a long greenhouse canopy. A single 7.7 mm (0.303 in) Type 89 machine gun formed the only defensive armament.
C5M
The army’s Ki-15-I had been received in time to make a significant impact at the beginning of the war with China. The Ki 15 I became operational during the second Sino Japanese war, and was joined in service in late 1939 and early 1940 by the Ki 15 II.
Plans had already been made to upgrade performance of the KI-15-I, this being achieved by installing the 671-kW (900-hp), smaller-diameter Mitsubishi Ha-26-I engine, its in¬corporation providing an opportunity to overcome what had been the major shortcoming of the type, a poor forward field of view past the large-diameter Nakajima engine. The improved version entered production for the army in September 1939 as the Ki¬-15-II, but before that the Japanese navy, impressed by the performance of this aircraft, ordered 20 examples of the Ki-15-II under the official designation Navy Type 98 Reconnaissance Plane Model 1, Mitsubishi designation C5M1 in 1938 (with 780 hp Mitsubishi Suisei 12 radials). The navy acquired two years later 30 C5M2 aircraft that were generally similar except for installation of the more powerful 708-kW (950-hp) Nakajima Sakae (Prosperity) 12 engine. These aircraft serving with two Sentais (air corps) of the naval air force.
The Ki 15 III, with the 1050 hp Ha 102 version, although capable of 530 km/h (329 mph), was itself surpassed by the more modern Mitsubishi Ki 46.
When production ended almost 500 of all versions had been built, the majority being in first-line service when the Pacific war started. Given the Allied codename ‘Babs’, the type was relegated to second-line roles in early 1943, but many survived to be used in kamikaze attacks at the war’s end.
Mitsubishi built 439 in successive models between 1936 40.
Ki-15 Engine: Naka¬jima Ha 8, 640 hp. Armament: one 7.7-mm (0.303-in) machine-gun Crew: 2
Ki-l5-I Powerplant: one 477-kW (640-hp) Nakajima Ha-S radial piston engine Maximum speed 480 km/h (298 mph) at 4000 m (13,125 ft) Cruising speed 320 km/h (199 mph) at 5000 m(16,405 ft) Service ceiling 11400 m (37,400 ft) Range 2400 km (1,491 miles) Empty weight 1400 kg (3,086 lb) Maximum take-off 2300 kg (5,071 lb) Wingspan 12.00 m (39 ft 4.4 in) Length 8.70 m (28 ft 6.5 in) Height 3.35 m (11 ft 0in) Wing area 20.36sq.m (219.16 sq ft) Armament: one 7.7-mm (0.303-in) machine-gun Crew: 2
Ki 15 II Engine: Mitsubishi Ha 102, 850 hp. Armament: one 7.7-mm (0.303-in) machine-gun Crew: 2
Ki 15 III Engine: Mitsubishi Ha 102, 1050 hp Max speed: 530 km/h (329 mph) Armament: one 7.7-mm (0.303-in) machine-gun Crew: 2
All Aero 