Stability Analysis of the Slowed-Rotor Compound Helicopter Configuration

Abstract

The stability and control of rotors at high advance ratio are considered. Teetering, articulated, gimbaled, and rigid hub types are considered for a compound helicopter (rotor and fixed wing). Stability predictions obtained using an analytical rigid flapping blade analysis, a rigid blade CAMRAD I1 model, and an elastic blade CAMRAD I1 model are compared. For the flapping blade analysis, the teetering rotor is the most stable, showing no instabilities up to an advance ratio of 3 and a Lock number of 18. With an elastic blade model, the teetering rotor is unstable at an advance ratio of 1.5. Analysis of the trim controls and blade flapping shows that for small positive collective pitch, trim can be maintained without excessive control input or flapping angles.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 2004
Accession Number
ADA529853

Entities

People

  • Matthew W. Floros
  • Wayne R. Johnson

Organizations

  • National Aeronautics and Space Administration

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Aeronautical Laboratories
  • Aircrafts
  • Airframes
  • Airspeed
  • Autogyros
  • Autorotation
  • Boundaries
  • Elastic Properties
  • Equations
  • Helicopters
  • Propulsion Systems
  • Rotary Wing Aircraft
  • Short Takeoff Aircraft
  • Tilt Rotor Aircraft
  • Unmanned Aerial Vehicles
  • Vehicles
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Aerodynamics/Aeronautics.
  • Aerospace Engineering