Flight test experience of a non-linear dynamic inversion control law on the VAAC Harrier

Abstract

This paper describes the development and flight test of a Non-linear Dynamic Inversion (NDI) control law on the VAAC Harrier. The aim of the flight trial presented here was to examine the behaviour of a simple control law designed using the method, in order to prove the concept. A basic pitch rate control law was designed and tested, with the aim of proving a simple first step. Overall, the flight test results exceeded expectations and no major problems were encountered. Now that the basic concept has been demonstrated in-flight, it should be a straightforwar d matter to build on previous work and extend this type of control law to the lateraldirectional axes. Additionally, the simple NDI control law provides a good basic control structure around which a variety of response types or advanced manoeuvre modes can be implemented.