Piasecki PA-97
The Piasecki Heli -Stat also: Piasecki PA -97 was a mid-1980s by the Piasecki Aircraft Company performed experimental arrangement for transporting heavy loads through the air. An airship was here combined as a lifting body with four helicopter rotors to be used as a load airship can.
The Heli -Stat airship consisted of the part of a U.S. Navy airship ZPG -2W type, which should provide the buoyancy and four helicopter rotors that came from Sikorsky S -58 helicopters and provide the dynamic lift should. The control is substantially the same as in a conventional helicopter. The four rotor units were connected to each other and are controlled by the helicopter pilot. The pilots in the other machines monitored while only their device.
The client was the U.S. Navy, which wanted to provide evidence for the U.S. Forest Service that it is possible to design aircraft with the logging even in difficult terrain inexpensive and ecologically. It was planned to 200 tons developments for the transport of loads.
Development began in 1979 in Lakehurst. 1984 had the carrier framework of the four rotors to be redesigned since it had failed in a stress test. The first flight of the provided with the machine identifier N1897Z took place on 26 April 1986.
On 1 July 1986, the plane crashed and was completely destroyed. Here, one of the pilots came around, three others were seriously, one slightly injured.
In the flight tests, a drop in performance in helicopter 3 was detected. Thereafter, the experiments were terminated, and the machine should be placed on the armature pole. Shortly before the mooring recorded a lateral wind gust the aircraft. The pilot could not compensate him with the available tax organs the movements on the ground and tried to start. The temporary suspension, which had no brakes or dampers, fell in vibration and rocking on what was passed on to the entire structure. Subsequently breaking the helicopter on the design.
The performance drop in helicopter 3 was attributed to a missing part in the connection of the throttle system in flight accident report. Other factors were added:
- Vibrations in the chassis
- Vibrations of the rotor system
- No brakes on the chassis
- No control possibility of the chassis
Specifications of the prototype
Similar projects
- On 8 July 2008 Boeing jointly with the Canadian company SkyHook announced a heli -Stat very similar device for a payload of up to 40 tonnes under the name JHL -40 ( Jess Heavy Lifter ) want to develop. 2010, the project was stopped due to lack of funding. It would be a government support in the order of 100 million U.S. dollars have been necessary, the cost to develop the first prototype was estimated at $ 220 million.
- Even in the Soviet airship history there after World War II concepts of using airships in forestry.