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On 1 July 1986, the PA-97 crashed immediately after liftoff on a test flight, killing one of the pilots. A gust of wind from the rear of the aircraft induced some movement across the ramp. The undercarriage responded badly to this, the bogies shimmying uncontrollably. Vibration in the framework then
202:
The helicopters used were aged examples of a long-established design. Their tail rotors were removed, their fuselages shortened and they were attached to a crude tubular aluminum framework beneath the helium-filled envelope. Four freely-castering twin-wheel bogies beneath the framework provided the
152:
The
Helistat concept was to augment the helicopters' dynamic lift with the static lift of an air buoyancy envelope. This would give greater maximum lift capability for heavy-lift work. At low weights (i.e. traveling to site without a payload) it would also free up the helicopters' rotor thrust for
218:. The vibration was sufficient to cause a structural failure as the starboard rear helicopter broke off its mounting, its rotors cutting into the gasbag. The unbalanced lift then made the vibrations worse and the remaining three helicopters broke free.
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as helicopter power increased), it is impractical to use a single helicopter rotor, so multiple rotors are arranged around the center of buoyancy of the envelope.
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J helicopters. The combination of a large blimp with powered lift made the 343 foot (104.57 m) long helistat the largest dynamic lift aircraft in the world.
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envelope. The sole prototype was lost during a test flight, killing a test pilot and injuring another four in the course of a single incident.
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moments are produced by the differential cyclic tilting of the rotors (i.e. one side forward, the other back). In forward flight, the
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to demonstrate a heavy vertical airlifter for harvesting timber from inaccessible terrain. The single demonstrator used a retired
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in New Jersey, making use of the long-established hangars for handling large airships. First flight was on 26 April 1986.
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undercarriage. Criticism has been expressed of the structural qualities and stress analysis of this framework.
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National
Transport Safety Board Brief on Accident to Piasecki Helistat 97-34J registered N1897Z
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To maintain coincidence of the dynamic and static lifts (otherwise the envelope would
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at the tail of the blimp also add their pitch and yaw control moments.
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forward thrust, requiring less dynamic lift and lower fuel burn.
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The PA-97 was built under a 1980 U.S. Navy contract for the
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was an
American experimental heavy-lift aircraft, built by
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Cancelled military aircraft projects of the United States
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Experimental helicopter/airship by
Piasecki Aircraft
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Aircraft of comparable role, configuration, and era
245:. If you have a source, you can help Knowledge by
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396:. Piasecki Aircraft Corporation. Archived from
143:Artist's conception of the Heli-Stat in service
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214:coupled with a helicopter phenomenon known as
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241:article is missing some (or all) of its
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208:Naval Air Engineering Station Lakehurst
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943:1981 Bristow Helicopters Wessex crash
930:Chicago Helicopter Airways Flight 698
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279:343 ft 0 in (104.57 m)
123:helicopters to a framework beneath a
536:"From Aerologger to 'Balloondoggle'"
505:"Airship Crashes At Base In Jersey"
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285:76 ft 0 in (23.17 m)
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79:Destroyed in crash on 1 July 1986
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480:Jane's Aviation Review: 1986-1987
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297:111,917 lb (50,765 kg)
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206:Test flights were made from the
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1184:1980s United States helicopters
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1164:Airships of the United States
948:1993 Llyn Padarn Wessex crash
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1189:Aircraft first flown in 1986
483:. Jane's. 1987. p. 63.
163:Differential changes to the
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1045:Piasecki/Vertol helicopters
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1034:Piasecki Helicopter/Vertol
938:1975 Kjalarnes S-55B crash
422:"NTSB Synopsis NYC86FHD01"
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369:List of airship accidents
50:Experimental heavy-lifter
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32:
273:8 seats, including pilot
923:Accidents and incidents
258:General characteristics
148:Helistat design concept
113:Piasecki PA-97 Helistat
544:Forest History Society
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135:Design and development
605:Military designations
540:Peeling Back the Bark
142:
994:Sikorsky S-70 family
990:Sikorsky S-61 family
992: •
458:"Helistat Disaster"
330:AeroLift CycloCrane
324:Related development
1123:VZ-8/PA-59 Airgeep
1087:H-25/HUP Retriever
195:envelope and four
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119:by fastening four
1169:Piasecki aircraft
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1101:Piasecki Aircraft
1077:H-16 Transporter
1067:PV-15 Transporter
1038:Piasecki Aircraft
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62:Piasecki Aircraft
16:(Redirected from
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1057:PV-3/HRP Rescuer
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966:In fiction: S-55
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467:on May 21, 2008.
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460:. Archived from
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394:"PA-97 Helistat"
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511:. July 2, 1986.
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520:External links
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243:specifications
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222:Specifications
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189:Forest Service
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71:26 April 1986
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18:Piasecki PA-97
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1072:PV-17 Rescuer
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877:Primary names
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759:Modifications
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686:Model numbers
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490:0-7106-0446-7
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400:on 2012-04-14
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363:Related lists
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305:Wright R-1820
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197:Sikorsky H-34
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104:Sikorsky H-34
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100:N class blimp
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68:First flight
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58:Manufacturer
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799:Heavy Lifter
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462:the original
431:December 13,
429:. Retrieved
425:
402:. Retrieved
398:the original
362:
361:
345:
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335:ZPG-2W blimp
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177:ruddervators
162:
155:
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112:
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85:Number built
824:Nite-Writer
594:S-58 family
357:Cargolifter
313:Performance
301:Powerplant:
247:adding them
169:cyclic tilt
1174:Quadrotors
1153:Categories
988:See also:
714:production
542:blog, the
531:Photograph
404:2010-09-24
375:References
127:-inflated
978:Operators
914:Whirlwind
884:Chickasaw
739:Whirlwind
552:(YouTube)
283:Diameter:
271:Capacity:
904:Seahorse
899:Seaguard
835:Piasecki
794:Defender
784:Airliner
777:OHA-S-55
723:Westland
587:Sikorsky
319:See also
239:aircraft
117:Piasecki
76:Retired
889:Choctaw
789:Bearcat
768:Orlando
712:License
465:(video)
289:Volume:
277:Length:
1138:PA-890
959:Topics
933:(1960)
909:Wessex
894:Seabat
734:Wessex
656:CH-126
596:&
487:
125:helium
1128:PA-97
1118:PA-39
1108:PA-2B
864:Elite
746:WS-55
639:HSS-1
340:EosXi
265:Crew:
237:This
158:pitch
129:blimp
121:H-34J
47:Role
1133:X-49
1092:VZ-2
1082:H-21
1052:PV-2
971:S-58
726:(UK)
703:S-62
698:S-58
693:S-55
649:HU2S
629:HO4S
622:H-52
617:H-34
612:H-19
598:S-62
590:S-55
485:ISBN
433:2023
426:NTSB
303:4 ×
111:The
855:VAT
644:HUS
634:HRS
173:Yaw
1155::
538:.
507:.
441:^
424:.
413:^
383:^
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435:.
407:.
267:1
249:.
20:)
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