Effect of Advanced Component Technology on Helicopter Transmissions

Abstract

Experimental tests were performed on the NASA/Bell Helicopter Textron (BHT) 500-hp advanced technology transmission (ATT) at the NASA Lewis Research Center.The ATT was a retrofit of the OH-58C helicopter 236-kW (317-hp) main rotor transmission, upgraded to 373 kW (500 hp), with a design goal of retaining long life with a minimum increase in cost, weight, and size. Vibration, strain, efficiency, deflection, and temperature experiments were performed and the results were compared to previous experiments on the OH-58A, OH-58C, and UH-60A transmissions. The high-contact-ratio gears and the cantilever-mounted, flexible ring gear of the ATT reduced vibration compared to that of the OH-58C. The ATT flexible ring gear improved planetary load sharing compared to that of the rigid ring gear of the UH-60A transmission. The ATT mechanical efficiency was lower than that of the OH-58A transmission, probably due to the high-contact-ratio planetary gears. Keywords: Transmission; Gears; Bearings; Transmission testing; Efficiency; Vibration; Strain; Deflections; Helicopters; High-contact-ratio gears.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1989
Accession Number
ADA219265

Entities

People

  • David G. Lewicki
  • Dennis P. Townsend

Organizations

  • National Aeronautics and Space Administration

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Accelerometers
  • Aircrafts
  • Army Aviation
  • Ball Bearings
  • Bearings
  • Detectors
  • Engines
  • Gas Turbines
  • Helicopters
  • Long Life
  • Measurement
  • Mechanical Engineering
  • Planetary Gears
  • Roller Bearings
  • Spiral Bevel Gears
  • Strain Gages
  • Test Stands

Fields of Study

  • Physics

Readers

  • Aerospace Engineering
  • Tribology (the study of the boundary interaction between sliding surfaces, lubrication, wear and friction).