Input Excitation Techniques for Aerodynamic Derivatives Estimation of Highly Augmented Fighter Aircraft

  • N. Shantha Kumar National Aerospace Laboratories, Bangalore
Keywords: SIMULINK based simulation, Fighter aircraft, Lateral directional aerodynamic derivatives


This paper presents the results of an investigation related to the estimation of lateral-directional aerodynamic derivatives of highly augmented and advanced fighter aircraft from the flight like response data. Different types of pilot inputs are used to generate aircraft response data in the engineer-in-loop flight simulator to determine which input excitation flight provide the most accurate estimates of aircraft stability and control derivatives. Also, MATILABI SIMULINK-based simulation platform is used to generate aircraft response with single-surface excitation to evaluate the usefulness of the method for stability and control derivatives estimation. The maximum likelihood estimation, based on output error utilisation technique is used to estimate the derivatives from the aircraft simulation response data. The results indicate that accuracy of the estimated derivatives improve with persistence excitation and single-surface excitation.

Author Biography

N. Shantha Kumar, National Aerospace Laboratories, Bangalore
Mr N Shantha Kumar obtained his MTech (Aerospace Engineering) from Indian Institute of Technology(IlT) Bombay, in 1987. Presently, he is working as Scientist at the Flight Mechanics and Control Division ofthe National Aerospace Laboratories (NAL), Bangalore. His areas of work include: modelling and parameteres timation of aerospace vehicles and sensor failure detection and management. He worked as Guest Scientistat the Institute of Flight Mechanics of German Amspace Research Establishment and Institute of FlightMechanics, Braunschweig, Germany, for six months during 1993. He is a member of the Aeronautical Society of India.


Maine, R.E. Parameter estimation of flight vehicles, Journal of Guidance, 1989, 12(5), 5 609-22.

Hamel, P.G. Aircraft parameter identification methods and their application: Survey and future 0.14 aspects. Parameter Identification. AGARD-LS- - 104, November 1979, Paper No. 1.

Klien, V. Estimation of aircraft aerodynami parameters from flight data. Prog. Aerosp. Sci., C 1989,26(3), 1-77.

Maine, R.E. & Murray, J.E. Application of parameter estimation to highly unstable aircraft. Journal of Guidance, 1989,12(3), 2 13-19.

K.W. & Maine, R.E. Practical aspects of extract stability and control derivatives from flight data. National Aeronautics and Space Administration, USA, 1976. NASA-TND-8209.

Plaetschke, E. & Schulz, G. Practical input signa design. Parameter Identification. AGARD-LS-104, November 1979, Paper No. 3.

Rekha,R. & k padmha, M. ALL S: A linearising link software-links flight simulation to control law design. National Aerospace Laboratories, India May 1990. NAL-PD-FC-9007.

Weiss, S.; Friehmelt, H.; Plaetschke, E. & Rohlf, D. X-3 1A system identification using single-surface excitation at high angles of attack. American Institute of Aeronautics & Astronautics, USA, 1995. Paper No. AIAA-95- 3436-CP.

Klien, V. Two biased estimation techniques in linear regression: Application to aircraft. National Aeronautics and Space Administration, USA, July 1988. NASA-TM-100649.

How to Cite
Kumar, N. (2013). Input Excitation Techniques for Aerodynamic Derivatives Estimation of Highly Augmented Fighter Aircraft. Defence Science Journal, 49(3), 187-196.
Aeronautical Systems