TABLE OF CONTENTS [1]The final proof of design of any control system is the demonstration of successful integration of the control system into the total vehicle of which it is a part. Such a demonstration of satisfactory and therefore safe design must include an assessment of the behaviour of the vehicle and its control system over the full range of normal and extreme environmental conditions to which it will be subject. Thus, in the case of an aircraft flight control system, this can only be achieved by testing the flight control system (FCS) when it is fully integrated into the aircraft and assessing it over the full operating envelope of the aircraft. Flight testing therefore represents the ultimate proof that the design of the FCS is fit for purpose, meets the design requirements and verifies that the design requirements themselves were valid.
Historically, the flight test process has been viewed as an independent check of the whole aircraft and its systems by the flight test team of pilots and engineers whose task was to assess the aircraft behaviour and identify any problems with the design. Any problems identified had to be understood and resolved by the designers and the modified aircraft reassessed by the flight test team. Up to the 1950s, the amount of flight data obtained from test flights was comparatively small and was made up of a combination of pilot's notes (on a kneepad), photographs of banks of gauges and data recorded on ultraviolet trace recorders...
