Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-26T03:12:56.405Z Has data issue: false hasContentIssue false
  • English
  • Français

An investigation of large amplitude wing-rock

Published online by Cambridge University Press:  04 July 2016

C. Evans
C. Evans*
Affiliation:
Department of Aeronautical EngineeringUniversity of Bristol
Get access Rights & Permissions [Opens in a new window]

Summary

The large amplitude wing-rock of a ground attack aircraft was investigated by the use of a small perturbation, linear stability analysis and a non-linear simulation of the aircraft dynamics. The linear stability analysis compared the results from a complete 6 degrees-of-freedom (DOF) coupled equation set with the results obtained using a 3-DOF dynamic stability axis set. The results showed an oscillatory instability that was caused by frequency coalescence of the primary pitch and yaw modes.

The simulation produced a rolling motion similar in nature to wing-rocks experienced in flight. The large amplitude oscillation was generated by the non-linear variations of the aerodynamic loads rather than by the instability predicted by the linearised dynamics. Specifically, the appearance of nonzero lateral moments at zero sideslip as well as shock-induced jumps in the rolling moment against sideslip curves were major contributors to the motion. These features of the static aerodynamic data are thus considered better warnings of the possibility of large amplitude wing-rock than is the negatively damped Dutch roll oscillation predicted by the linearised analysis.

Type
Research Article
Information
The Aeronautical Journal , Volume 88 , Issue 873 , March 1984 , pp. 51 - 57
Copyright
Copyright © Royal Aeronautical Society 1984 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Ross, A. J. and Foster, G. W. An Investigation of the Dutch Roll and Wing Rock Oscillations of a Gnat Trainer Aircraft: Flight Tests and Linear Analysis. RAE TR 78032, 1978.Google Scholar
2. Johnston, D. E. Ashkenas, I. L. and Hogge, J. R. Investigation of Flying Qualities of Military Aircraft at High Angles of Attack. AFFDL-TR-74-61, 1974.Google Scholar
3. Hwang, Chintsun and Pi, W. S. Some Observations on the Mechanism of Aircraft Wing Rock. Journal of Aircraft, 1979, 16, 6.Google Scholar
4. Kohiyar, F. A. and Davis, N. J. Analysis of the Wind Tunnel Tests for the Investigation of High Incidence Characteristics of the Harrier GR. Mk 3. BAe-KAD-R-Har-2543, British Aerospace Kingston, 1979.Google Scholar
5. Bore, C. L. Post/Stall Aerodynamics of the Harrier GR1. Paper 19, Fluid Dynamics of Aircraft Stalling, AGARD-CP-102, April 1972.Google Scholar
6. Kalviste, J. Aircraft Stability Characteristics at High Angles of Attack. Dynamic Stability Parameters, AGARD-CP-235, Athens, 1978.Google Scholar
7. Kohiyar, F. A. A Method fpr Predicting Departures at High Incidence from Static Aerodynamic Derivative Data. BAe-KADR-GEN-2582, British Aerospace Kingston, 1981.Google Scholar
8. Hopkin, H. R. A Scheme of Notation and Nomenclature for Aircraft Dynamics and Associated Aerodynamics. RAE TR 66200, Part 5-Appendices, 1966.Google Scholar
9. ANON, E02DAF, Least-squares Surface Fit of Bicubic Splines. NAG FORTRAN Library, 1475/0, Mk 6, May 1977.Google Scholar