I consider it a great honour, and most appropriate that the first function to be performed by a Chairman of the Flight Simulation Group, the youngest group of the Royal Aeronautical Society, is to present this paper to the Section which represents the interests of the younger members of the Society. I bring the best wishes of the Group to the Graduates and Students Section and I hope that this paper will stimulate an interest in the subject of flight simulation. The established members of the simulator fraternity who are present this evening will at least forgive me, and some, I hope, may agree with me, when I suggest that simulation is one of those areas of aeronautical engineering where a young and fresh approach to the problems encountered is likely to pay dividends.

By way of introduction, I suggest you consider for a moment of four aircraft as dissimilar as a small general aviation aircraft, a large transport such as the Airbus, a glider and finally a fighter aircraft such as the Tornado. As regards handling in the air of these widely differing flying machines, their most significant common quality is perhaps that they can all be flown by a human pilot.

In the definition of the desirable handling qualities of these aircraft, one might—in complete innocence—expect to find a description of such desirable qualities in terms of the behaviour, capabilities and limitations of the human pilot, which one would, of course, expect to be independent of class or category of aircraft.

This Second European Pioneers Day Lecture has two main themes: to pay tribute to the memory of Professor Dietrich Küchemann and second, to comment on how computers and wind tunnels should be used to assist aircraft design. These are not separate themes; as I will show, they are closely interrelated. You may be surprised that I feel that a lecture on the second theme is needed. However, in the past ten years, there has been a dramatic advance in theoretical methods on aerodynamics and in particular, for transonic flow calculations. This has created new opportunities but if we are not alert, there are also dangers in the new situation. My aim in this lecture is to draw attention to the opportunities and the dangers. I want to express my belief that computers will never completely replace the wind tunnel; we must learn to use them in partnership; only in this way can we hope to compensate for the limitations of any theory or the deficiencies of any experiment and finally, we must never forget that both are only tools; they are not a substitute for the human brain. Ideas, concepts, inventive genius, intuition, experience, the ability to interpret and draw logical conclusions will always be needed: in short, without scientists such as Professor Küchemann, the computers and the wind tunnels will be of little value.

The present energy situation has caused engineers to look more closely at methods of energy recovery which have previously received only limited attention due to the availability of cheap and plentiful fossil fuels. One of these methods is the use of an airscrew, or windmill, to convert wind energy into mechanical energy. There are a number of disadvantages in the utilisation of wind energy: the power available is relatively low for the size of plant involved and the supply is intermittent, but on the other hand the energy is free and available in most areas.

The economic feasibility of using windmills on a scale large enough to supply the national grid system is debatable, but there is certainly a demand for small units suitable for the individual domestic consumer.