A THEORETICAL INVESTIGATION OF THE EFFECT OF CROSS-CONTROL DERIVATIVES ON THE STABILITY CHARACTERISTICS OF AIRPLANES DESIGNED FOR FLIGHT AT HIGH MACH NUMBERS

Abstract

Linearized equations of motion were used to determine the lateral stability characteristics of a high-speed airplane with aerodynamic controls at Mach 6 and at an altitude of 125,000 feet. The period and damping of the oscillatory mode, the damping of the a periodic modes, and the ratio of the roll angle to the sideslip angle were analyzed to determine the effects of the cross control derivatives. Results show that an increase in the roll-damper gain causes a relatively large increase in the damping with a moderate increase in the frequency of the Dutch roll mode as a result of the cross-control effectiveness. This could cause critical ratios of the roll angle to the sideslip angle if a negative effective dihedral exists. In addition, when damper gains are relatively large, the cross-control derivatives could overcome divergence that results from a negative effective dihedral and a small directional derivative.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1962
Accession Number
AD0273568

Entities

People

  • Lawrence W. Brown

Organizations

  • National Aeronautics and Space Administration

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Air Force
  • Air Force Facilities
  • Aircrafts
  • Airplanes
  • Altitude
  • Automatic
  • Directional
  • Dynamic Pressure
  • Equations
  • Equations Of Motion
  • Flight
  • Frequency
  • High Altitude
  • Mach Number
  • Molecular Dynamics
  • Research Aircraft
  • Resonant Frequency

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Control Systems Engineering.