When the DC-3 aircraft came along, the Japanese immediately recognized its potential, especially since they had such great success with the DC-2. Great Northern Airways and the Far East Fur Trading Company (another Japanese military front company) purchased at least 21 DC-3s from Douglas between 1937 and 1939. The first intended for KLM as PH-ARA, but canceled, arrived in Japan on December 6, 1937.
These transports were operated by Dai Nippon Koku and impressed into Imperial service during the war. The surviving transports were scrapped at the end of the war.
On February 24, 1938, a Japanese manufacturer, Mitsui (a subsidiary of Nakajima Hikoki), purchased the production rights and technical data to the DC-3 airplane for $90,000. Unknown to the United States at the time, the sale was directed behind the scenes by the Imperial Japanese Navy (who was planning on using the type in the invasion of the East Indies). They saw the potential in the DC-3 to serve as a military transport. Mitsui and Showa Hikoki, another manufacturer, made many engineering revisions to take advantage of standard Japanese parts and raw materials. Japan also purchased and imported some machinery from the U.S. to speed up production. The first Japanese-produced DC-3 appeared in September 1939. By May 1941, the fifth DC-3 left the Showa factory, this one using the last Douglas-built fuselage. By July 1941, the factory was producing one DC-3 transport aircraft per month, far short of the one DC-3 plane per day demanded by the Imperial Japanese Navy. Finally by 1942, the production quota was reached.
This is a captured Showa-built “Tabby” L2D3, Navy Type “0” Transport Model 11 seen in US markings after capture in the South West Pacific area. Note the fuel dump valves visible at the wing trailing edge present on the pre-war Showa-built DC-3s. (National Archives.)
This close-up view of a Japanese L2D3 shows the additional side windows aft of the cockpit plus the windows added in the forward access door. Removal of the bulkhead behind the pilots gave better rearward visibility. Photograph courtesy National Archives.
Although ostensibly purchased for civilian use, the Japanese DC-3s were given a Navy designation L2D2 (L-transport, 2-second Navy type, D2-second Douglas design). L2D1 became the designation for imported DC-3s. The Japanese built eight separate sub types in two basic configurations, straight airline type, and cargo planes.
Japan modified the transport design for easier production. In addition, they replaced the Pratt & Whitney 1,000 hp engines they imported with 1,000 hp Mitsubishi Kinsei 43 radial engines.
After two years of manufacture, Nakajima had built 71 C-47 transport aircraft (designated L2D2 Navy Type 0 Transport Model 11) and switched to manufacturing combat aircraft. Meanwhile, Showa built 416 DC-3 type aircraft, including 75 cargo versions with the “barn door” and reinforced floor (designated L2D2-1). The first Japanese military version with wide cargo doors, remarkably similar to the U.S. C-47, appeared about the same time as the C-47. There are strong suspicions that it was a copy, and not the product of an independent design. The Japanese manufactured 75 cargo versions of the DC-3.
Japan’s civilian DC-3 was similar to the U.S. version, but the military version was noticeably different. The main production version of the Japanese DC-3 appeared in four variants; the L2D3 was a personnel transport powered by 1,300-hp Kinsei 51 radials, the L2D3G, also a personnel transport but with Kinsei 53 radials, the L2D3-1 and L2D3-1a were cargo transports powered by Kinsei 51s and 53s respectively. Some obvious differences were the three extra windows behind the cockpit, larger engine cowlings on the 1000-hp Kinsei-43 engines, and larger spinners on the propellers. They moved the cockpit bulkhead back 40 inches so all four men were in one compartment. The military version included a 13mm machine gun turret in the navigator’s dome and a 7.7mm machine gun in the rear window on each side of the fuselage. This aircraft was designated L2D4 Navy Type 0 Model 32.
After the war, inspection and flight testing of these later versions showed that because of Japan’s use of plywood on fairings, tail cone, surface controls, and doors, it out-performed the U.S. version. The 30 part wood, part metal versions were sent to the scrap pile.
Because of shortages of strategic materials, Japan redesigned less critical components in the DC-3s and replaced the metal versions with wood. These parts included rudder, stabilizer, ailerons, fin, elevator, and entrance door. As many as 30 transports with these wooden parts entered service apparently with satisfactory results. The success of this modification and the growing need for metal forced Japan to design an all-wooden version of the DC-3, which they designated the L3D5. The Showa facility was to have produced this new version in quantity but the government shifted the priority of the factory to building bomber and suicide aircraft.
It is not certain how many wooden Gooney Birds were built, but the occupation troops found at least one all-wooden C-47. Japan had available aviation grade birch, spruce and other woods. However, they had begun to suffer setbacks in the logging and transportation of this material. They had long been a producer of high-grade plywood and veneers and this form of material substitution for metal should not have surprised the Allies. The Japanese were superior artisans at shaping wood, and had mastered the complex shape of the C-47. Another strategic problem that would have delayed plans to produce the wooden version was the increasing shortage of adhesives for the bonding process. The war in Indo-China, where Japan obtained much of her raw material, was going poorly for the Japanese. The government had already given glue-making materials higher priorities and engineers had been forced to experiment with substitutes like animal bone, skin, blood, milk, soybeans and corn.
The all-wood Gooney Bird was a static test fuselage but preparations were underway to mount two 1,560-hp Kinsei-62 engines on the airframe. Expert opinion is that it required the larger engines to lift the heavier structural weight. It never flew, and went to the scrap pile with most of Japan’s DC-3s. It is believed, however, that a few Japanese versions went to the Chinese Air Force.
Japan built a total of 487 C-47 transports from 1939 to 1945. In 1955, the first Douglas-built DC-3 went into service with Japan Airways, the civilian airline. It was an ex-American Airlines machine. It was soon followed by more DC-3s and ex-C-47s.
The panel on “Tess” (National Archives)
The Allies code-named the L2D3s “Tabby” and its sister ship, the L2D2, the Japanese version of the DC-2 “Tess”
.©Copyright Henry M. Holden 1996, 2013
For the complete story on the Douglas DC-3 see “Legacy of the DC-3”