Indicated airspeed estimation filter

Abstract

Indicated Airspeed (IAS) data play a critical role in aircraft flight control, both for pilot and Automatic Flight Control Systems. In unmanned aerial vehicles (UAVs) loss of IAS data could result in loss of aircraft control. This paper addresses the problem of IAS estimation after airdata sensor failure. A complementary filter with cutoff frequency dynamically adapted to flight condition is proposed. The complementary filter produces Airspeed estimation using aircraft attitudes, vertical speed and along heading acceleration. Filter output accuracy has been validated using about 100 hours of flight data at different speeds and altitudes. Comparison between actual flight data and the estimated IAS has shown a good match for all flight conditions, demonstrating the feasibility of using filter output data in case of airdata sensor failure.