INVESTIGATION OF HYDRAULIC POWER TRANSMISSION SYSTEMS FOR V/STOL AIRCRAFT

Abstract

A comparison is presented between the efficiency and weight of the UH-1 helicopter gear transmission and speed reducer systems to a hydraulic power transmitting system for the UH-1. The hydraulic transmission system is composed of a 'turbine speed' hydraulic pump and a hydraulic motor. The hydraulic transmission system utilizes recently developed non-Newtonian, viscoelastic fluids which greatly reduce fluid friction losses, increase hydraulic component volumetric efficiency, and allows a substantial reduction in connecting fluid line sizes without the usual high fluid friction losses which normally result from use of small lines. The results of the comparison show the hydraulic transmission system efficiency closely matches the gear system efficiency, and the hydraulic transmission system is lighter than the gear system. A limited aircraft effectiveness study shows that the flexibility of design which is possible with a hydraulic transmission can result in an increase in useful engine horsepower, reduced infrared signature, improved foreign object damage protection and a reduction in engine/airframe vibration. The hydraulic transmission system is based upon hydraulic components which were chosen from an industry and government agency wide search for the best hydraulic components. Design data and calculated and test performance are shown for the hydraulic components. Test data is shown for the fluid flow friction reducing hydraulic fluid. Vulnerability, maintenance, logistics and operational considerations for a hydraulic transmission are presented.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1967
Accession Number
AD0661311

Entities

People

  • Horace R. Crawford
  • Jerome L. Overfield

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Aircraft Equipment
  • Aircrafts
  • Airframes
  • Contracts
  • Cooling
  • Flow Rate
  • Fluid Flow
  • Friction
  • Heat Transfer
  • Heat Transfer Coefficients
  • Helicopters
  • High Pressure
  • Jet Engines
  • North America
  • Oil Coolers
  • Short Takeoff Aircraft
  • Tail Rotors

Fields of Study

  • Engineering

Readers

  • Computer Networking
  • Petroleum Engineering