The first formal airplane (The Seishiki-1 Experimental Aeroplane) was a military aircraft prototyped by the Imperial Japanese Army. Although it is called "formal", it means "planned as a formal machine" and had not actually been adopted.
In May 1915 (Taisho 4), the Provisional Military Balloon Research Association
(PMBRA) began designing an aircraft that adopted a tractor engine layout that brought together the latest technologies at the time, unlike the pusher-type airframes that had been developed so far. The design committee consists of five members, including Engineer Shuhei Iwamoto, Captain Yoshihide Sakurai, Captain Matsui, Lieutenant Hide Sawada, and Lieutenant Kenjiro Nagasawa. In November of the same year, the production of one prototype was started at the Tokorozawa factory of the PMBRA, and it was completed on April 30, 1916 (Taisho 5). The first flight was made at Tokorozawa Army Airfield on May 6, the same year, but after takeoff, the engine stopped due to a drop in fuel tank pressure, causing a crash landing. Lieutenant Sawada, who was piloting, was slightly injured.
After that, the fuel tank and engine were refurbished to repair the aircraft, and the test was started again in December 1916, but the performance expected to be comparable to the new aircraft in each European country was far below expectations and stability. Defects were also revealed, and it was only used as an experimental machine. On July 24, 1917 (Taisho 6), this aircraft was struck by the army Maurice Farman type-1914 reconnaissance aircraft on the ground and was wrecked and dismantled.
The aircraft was a biplane with a wooden frame, plywood and upholstered cloth, and the design was based on the design data of German LVG D.9. It featured radiators on both sides of the fuselage. The main wing could be folded in consideration of rail transportation. After the wreck, repairs include the addition of an auxiliary fuel tank inside the upper wing, the addition of inter wing struts, and the removal of skids from fixed undercarriage.
Overall length : 9. 35 m, Span : 15. 10 m, Overall height : 3. 00 m, Wing area : 40.5 m2
Gross weight : 1,100 kg
Engine : Mercedes-Daimler water-cooled in-line 6-cylinder gasoline (up to 110 hp) x 1
Maximum speed : 108 km / h, Endurance : 7 hours
Armament : Swivel light machine gun x 1, Some bombs, Crew : 2