Warplanes of Japan: Mitsubishi Ki-15

(IJNAF Photo)

Mitsubishi C5M Karigane, J-BAAL after joining IJNAF.

The Mitsubishi Ki-15 (雁金, Karigane, English: Wild Goose) Army Type 97 Command Reconnaissance aircraft (九七式司令部偵察機, Kyunana-shiki sireibuteisatsuki) was a Japanese reconnaissance aircraft and a light attack bomber of the Second Sino-Japanese War and Pacific War. It began as a fast civilian mail-plane. It was a single-engine, low-wing, cantilever monoplane with a fixed tailwheel undercarriage; it carried a crew of two. It served with both the Imperial Japanese Army and Navy (as the C5M). During the Second World War it was code-named "Babs" by the Allies.

The Ki-15 was designed by the Mitsubishi corporation to meet an Imperial Japanese Army Air Force requirement of 1935 for a two-seat, high-speed reconnaissance aircraft. The resulting aircraft was a low-wing cantilever monoplane with a fixed, spatted undercarriage, similar to other all-metal stressed-skin monoplanes developed elsewhere in 1930s, such as the Heinkel He 70 and the Northrop Alpha. Power was by a single Nakajima Ha-8 radial engine, giving 560kW (750 hp) at 4,000 m (13,120 ft). The first prototype flew in May 1936, with testing proving successful, the aircraft meeting all performance requirements, reaching a speed of 481 km/h (299 mph) and showing good handling characteristics.

Service testing was completed without difficulty and the type was ordered into production under the official designation Army Type 97 Command Reconnaissance Aircraft Model 1. In May 1937, a year after the first flight, delivery of the first of 437 production aircraft to the army began.

The Ki-15-I was almost immediately placed into operational service at the beginning of the war with China in 1937. The aircraft proved useful in the early period of the Second Sino-Japanese War and performed missions deep into Chinese strategic rear areas, as far as reaching Lanzhou, and in particular serving as pre-strike guide and post-strike observation during the years-long Battle of Chongqing-Chengdu. Its high speed gave it a distinct advantage until the Chinese Air Force acquired Soviet-made Polikarpov I-16 Type 17 fighters; a Ki-15 was shot down along with three bombers by I-16 Type 17 fighters of the 24th PS, 4th PG over Liangshan Airbase on 20 May 1940. It was used for level bombing, close support and photo reconnaissance before being eventually replaced by the Mitsubishi Ki-30.

Plans were already in hand to improve the Ki-15-I, and in September 1939 theKi-15-II was put into production with the 671 kW (900 hp) Mitsubishi Ha-26-1;the smaller diameter of this both reduced drag and overcame one of the majorshortcomings of the initial version: poor forward field of view past the large-diameter of the initial Nakajima Kotobuki engine. The improved version entered production in September 1939 as the Ki-15-II.

The Japanese Navy, impressed by the performance of this aircraft, ordered 20examples of the Ki-15-II under the designation “Navy Type 98 Reconnaissance Aircraft Model 1," or Mitsubishi designation C5M1, even before the Army.The Navy subsequently acquired 30 C5M2 aircraft which had an even more powerful708 kW (949 hp) Nakajima Sakae 12 engine. They were used for reconnaissance duties. In further development, the army also experimented with an even morepowerful engine with 783 kW (1,050 hp) Mitsubishi 102 radial in the Ki-15-IIIwhich did not enter production.

When production ended, approximately 500 examples of all versions of the Ki-15had been built, the majority in front-line service when the Pacific War began.By 1943, the Ki-15 had been relegated to second-line roles, but numbers wereexpended in kamikaze attacks in the closing stages of the Second World War.

Despite the relatively weak engine (by later standards) and fixedundercarriage, the Ki-15 was remarkably fast. During the initial flighttesting, the newspaper Asahi Shimbun obtained permission to purchase the secondprototype. The aircraft was given the designation Karigane ('wild goose'),flying on 19 March 1937, being named Kamikaze and registered as J-BAAI.

It was the first Japanese-built airplane to fly to Europe and caused asensation in 1937 by making the flight between Tokyo and London, for thecoronation of King George VI and Queen Elizabeth, between 6 April 1937 and 9April 1937 in a flight time of 51 hours, 17 minutes and 23 seconds, a world recordat the time.[6] Following the success of the Japan-England flight, a smallnumber of Ki-15s were sold to civil customers. One of the early productionaircraft was named "Asakaze" (J-BAAL) and was also used by the AsahiShimbun; others were used by various civilian operators as mail-planes.

Variants
Karigane I : Prototype version for civilian use.
Ki-15-I (Army Type 97 Command Reconnaissance Aircraft Model 1) : Initialproduction variant for the Japanese Army, with Nakajima Ha-8 (Army Type 94) 640hp at take-off, 900 hp at 11,810 ft (3,600 m).
Ki-15-II (Army Type 97 Command Reconnaissance Model 2) : Improved Armyproduction version with smaller but more powerful 14-cylinder MitsubishiHa-25-I (Army Type 99 Model 1) engine, with 850 hp at take-off and 900 hp (670kW) at 3,600 m (11,810 ft). This gave an increased maximum speed of 317 mph at14,205 ft (510 km/h at 4,300 m), roughly comparable with fighters like HawkerHurricane or the Nakajima Ki-43 Hayabusa. Rate of climb was even more improved:16,400 ft (5,000 m) in 6 min 49 seconds, and was achieved despite the increasein weight (empty, normal, max: 3,510 vs 3,084 lb, normal 4,826 vs 4,482 and max5,470 vs 5,071 lb). Maiden flight was in June 1938 and production started inSeptember 1939.
Ki-15-III : Proposed upgraded version; did not enter production. It had theMitsubishi Ha-102 engine (1,080 hp (810 kW) at take-off, 1,055 hp (787 kW) at2,800 metres (9,185 ft) and 950 hp (710 kW) at 5,800 m (19,030 ft)), with a topspeed of 329 mph (530 km/h), roughly the same as Mitsubishi Ki-46"Dinah". The latter was expected to be far better in other ways(endurance, two engines, etc.) so never went into production.
C5M1 (Navy Type 98 Reconnaissance Aircraft Model I) : Improved version ofKi-15-I for the Japanese Navy
C5M2 (Navy Type 98 Reconnaissance Aircraft Model 2) : Upgraded version of C5M1with more powerful engine for the Japanese Navy. (Wikipedia)

(IJAAF Photo)
The Mitsubishi Ki-15.

(SDASM Archives Photo)

Mitsubishi, Ki-15, Babs Command Recon Aircraft. First prototype Mitsubishi Karigane C/N 1501. "Kamikaze", owned by the Asahi Shimbun newspaper group.

(SDASM Archives Photo)

Mitsubishi Karigane J-BAAL Asakaze operated by the Asahi Shimbun newspaper.Mitsubishi Ki-15