Hostname: page-component-76fb5796d-x4r87 Total loading time: 0 Render date: 2024-04-26T03:08:34.031Z Has data issue: false hasContentIssue false
  • English
  • Français

Parameter estimation using unsteady downwash model from real flight data of Hansa-3 aircraft

Published online by Cambridge University Press:  27 January 2016

R. Kumar  and
A. K. Ghosh
R. Kumar*
Affiliation:
Aerospace Engineering Department at IIT-Kanpur, Kanpur, India
A. K. Ghosh*
Affiliation:
Aerospace Engineering Department at IIT-Kanpur, Kanpur, India
*
rakpec@iitk.ac.in
akg@iitk.ac.in
Get access Rights & Permissions [Opens in a new window]

Abstract

The paper presents the estimation of longitudinal aerodynamic parameters from simulated as well as real flight data using an unsteady downwash model. The task of parameter estimation was accomplished using the Maximum Likelihood (ML) method in the frequency domain for the Hansa-3 aircraft. The presented work pertains to the aircraft having a semi-sweptback wing configuration, however, the work reported earlier considered a rectangular wing configuration. A simple vortex system was used to model downwash effects in the longitudinal equations of motion. First, it was established that the indicial lift function had a minor or negligible influence on aircraft motion and on the estimated aerodynamic parameters using simulated data for the configuration of Hansa-3 aircraft. Next, two parameter extraction algorithms were used for parameter estimation using simulated data (with unsteadiness only in downwash) and real flight data (Hansa-3 aircraft). The first algorithm included unsteadiness only in downwash while the second neglected all the unsteady effects. It was observed from the results obtained that if unsteady effects were omitted from the parameter estimation algorithm, the extracted parameters included the effects of unsteady aerodynamics. Therefore, application of the extraction algorithm in the two modes provides a convenient means of separating steady-state and acceleration derivatives.

Type
Research Article
Information
The Aeronautical Journal , Volume 115 , Issue 1171 , September 2011 , pp. 577 - 588
Copyright
Copyright © Royal Aeronautical Society 2011 

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. Roskam, J. Methods for estimating Stability and control Derivatives for Conventional Subsonic Airplanes, Roskam Aviation and Engineering Corporation, 1973.Google Scholar
2. Hamel, P.G. Aircraft Parameter Identification Methods and their Applications Survey and Future Aspects, AGARD, 15–104, November 1979, Paper 1.Google Scholar
3. Iliff, K.W. Parameter estimation for flight vehicle, J Guidance, Control and Dynamics, 1989, 12, (5), pp 609–622.Google Scholar
4. Klein, V. Estimation of aircraft aerodynamic parameter from flight data, Progress in Aerospace Sciences, 1989, 26, (1), pp 1–77.Google Scholar
5. Hamel, P.G. and Jategaonkar, R.V., The Evolution of Flight Vehicle System Identification, AGARD, DLR Germany, 8-10 May 1995.Google Scholar
6. Klein, V. and Morelli, E.A. Aircraft System Identification – Theory and Practice, AIAA Education Series, Reston, Virginia, USA, 2006.Google Scholar
7 Jategaonkar, R.V. Flight Vehicle System Identification – A Time Domain Methodology, AIAA Progress in Aeronautics and Astronautics, 216, AIAA, Reston, VA, USA, August 2006.Google Scholar
8. Queizo, M.J., Wells, W.R. and Keskar, D.A. Approximate Indicial Lift Function for Tapered, Swept Wings in Incompressible Flow, NASA, TP-1241, 1978.Google Scholar
9. Queizo, M.J., Wells, W.R. and Keskar, D.A. Inclusion of Unsteady Aerodynamics in Longitudinal Parameter Estimation from Flight Data, NASA, TP-1536, 1979.Google Scholar
10. Wells, W.R. and Queizo, M.J. Simplified Unsteady Aerodynamic Concepts with Application to Parameters Estimation, AIAA Paper 77-1124, August 1977.Google Scholar
11. Wells, W.R. and Queizo, M.J. Simplified unsteady aerodynamic concepts with application to parameters estimation, J Aircr, 16, February 1979.Google Scholar
12. Queizo, M.J., Wells, W.R. and Keskar, D.A. Influence of Unsteady Aerodynamics on Extracted Aircraft Parameters, AIAA Paper 78-1343, August 1978.Google Scholar
13. Ghosh, A.K. Parameter Estimation of an Augmented Airplane Including Unsteady Effects, M.Tech Thesis, IIT Kanpur, India, January 1989.Google Scholar
14. Keskar, D. Maximum Likelihood Identification of Aircraft Parameters with Unsteady Aerodynamic Modelling, 17th Aerospace Sciences Meeting, NY, USA, 15-17 January, 1979.Google Scholar
15. Wells, W.R., Banda, S.S. and Quam, D.L. A model for unsteady effects in Lateral Dynamics for use in Parameter Estimation, AIAA Paper 79-1638, 1979.Google Scholar
16. Wells, W.R. and Quam, D.L. Model for unsteadiness in lateral dynamics for use in parameter estimation, J Aircr, 1979, 17, (9).Google Scholar
17. Singh, J. Unsteady Aerodynamic Modelling for Parameter Estimation from Flight Data, PhD Thesis, IIT Kanpur, India, April 1993.Google Scholar