The Piasecki Heli-Stat project began in the mid 1970s with a view to combining the lift capability of a lighter-than-air vehicle with the precise manoeuvrability of the helicopter, and following support from the US Forestry Service and the US Navy, construction of a prototype Heli-Stat began at Lakehurst, New Jersey, in 1979. The hybrid aircraft uses an airship-based envelope, attached via a skeletal structure to the front fuselage portions of four Sikorsky SH-34J helicopters, each powered by a standard Wright radial engine driving the conventional main rotor system and mounted at the four corners of the aircraft. The tail rotors are replaced by large diameter propellers to provide propulsion and full controllability.
At the beginning of 1984 it was expected that the Heli-Stat would fly in 1985, following a redesign of the structure which had failed under load tests. The following data is provisional
Richard Burke, 29.07.2008
I spent 7 years on this project starting first at the MAIN engineering facility drafting this monster along with 15 other people on Island Avenue in Philadelphia and later moved to Lakehurast during the structural pluck tests. I was there up until the ground manuvering tests where being performed. If you have any questions I can answer them I was over every single part of the airframe / Sh34J's (Modified) and the aerostat (ZPG2 envelope). [The photo] was a roll out for a photo op dog and pony show note the lack of inverted v fins on the aerostat and the lack of pusher props on the helos also US Forrest Service was not painetd on the envelpope yet . I am actually in this photo aft center stern of ship next to the guy with the bike, Joe O'Halleren
It was truly a combination of four SH-34 helicopters and a ZP-3 patrol blimp. It had B-52 landing gear and P-51 reduction gear boxes driving H-3 tail rotors as pusher props.
Engines: 4 x Wright R-1820-84A, 1525shp
Overall width: 60.05m
Overall length: 74.07m
Empty weight: 24895kg
Gross weight: 50469kg
Maximum speed: 132km/h
Service ceiling: 3810m
Range with maximum payload: 80km