Designed circa 1958 as a high-speed short-haul aircraft, the Jacobs 104 was originally flown as a pure helicopter, as shown in the photograph above. Subsequently, a pusher propeller was fitted at the extreme tail.
It will take off as a helicopter; but in cruising flight it will be possible to transfer power to the pusher propeller, with the rotor auto-rotating and the majority of the lift coming from the fixed wings.
A feature of the Model 104 is the use of a Jacobs-designed engine "package", consisting of the engine and complete transmission system. It is claimed to be 20 per cent lighter than conventional helicopter power plants, enabling one extra passenger to be carried. Also, by using moulded fibreglass and Plexiglass panels to cover the forward fuselage, high strength is combined with light weight, and the surface requires no painted or doped finish.
Engine: 350 h.p. Jacobs R-755EH
Rotor diameter: 36 ft.
Rotors: 3-blade main; 3-blade tail; 3-blade propeller.
Overall length: 26 ft. 4 in.
Loaded weight: 3,475 lb.
Max. speed: 175 m.p.h.
Typical range: 300 miles at 157 m.p.h.