Accession Number : AD0779502

Title :   Artificial Icing Tests UH-1H Helicopter. Part I.

Descriptive Note : Final rept. 17 Sep-29 Oct 73,


Personal Author(s) : Griffith,Warren E. , II ; Smith,Raymond B. ; Brewer,Larry K. ; Hanks,Marvin L. ; Reid,James S.

Report Date : JAN 1974

Pagination or Media Count : 65

Abstract : A limited evaluation of the capability of the UH-1H helicopter to fly in an artificial icing environment was conducted at Fort Wainwright, Alaska, from 17 September through 29 October 1973. Testing was performed by the United States Army Aviation Systems Test Activity and consisted of 13.7 productive flight hours. During this test, one enhancing characteristic, three deficiencies, and four shortcomings were noted. Heat from the engine exhaust prevents ice from accumulating on the tail rotor and on inboard sections of the synchronized elevator and vertical stabilizer, and is an enhancing characteristic. The deficiencies are asymmetrical shedding of ice from the main rotor system, obscured forward vision due to formation of ice on the windshield, and the inability to maintain autorotational rotor speed within operational limits with ice accumulation on the main rotor blades. Four shortcomings attributable to the UH-1H helicopter are obscured downward view due to formation of ice on the chin bubble, the scratching of the windshield by the wiper blade, large-amplitude oscillations of the FM whip antenna after accreting small amounts of ice, and inaccurate outside air temperature indications for flight in icing conditions. (Modified author abstract)

Descriptors :   *Helicopters, *Ice formation, Windshields, Airframes, Windows, Helicopter rotors, Flight control systems, Cold weather operations, Cold weather tests

Subject Categories : Helicopters

Distribution Statement : APPROVED FOR PUBLIC RELEASE