The first post-war Japanese helicopter designed for quantity production, the Yomiuri Y-1 developed as a project to commemorate the resumption of aviation by the Yomiuri Shimbun, and was produced with a prototype research subsidy from the Ministry of International Trade and Industry.
In 1953, Itogawa Eizo and Horikoshi Jiro, two of Japans most distinguised wartime aircraft designers, helped form the Japan Helicopter Association with a grant from MITI and the support of the Yomiuri Shimbun, a leading daily newspaper. Their design, the Yomiuri Y-1, was powered by the wartime Kamikaze-3 engine.
The project was abandoned when it failed to acquire U.S Patents for helicopter design. It took a lot of time to solve the anti-vibration measures, and it was not put into production.
Engine: Hitachi Jinphu III seven-cylinder radial, 150hp
Rotor diameter: 10.0m / 32 ft 10 in
Length: 12.2m / 40 ft 2 in
Height: 3.60m
Empty weight: 1,166 lb
Gross weight: 1,650 lb
Maximum speed: 156km/h / 96 mph
Cruising range: 200 mi
Seats: 2
All Aero 