Many others have told of the thrills of seeing the early flying machines leave the ground for the first time. I also was fortunate enough to see many pioneer flights at Colindale where I used to go during the school holidays; these flights absorbed my interest, and I suppose started me off with the thirst for aviation, which persisted throughout my later life. There is no doubt that the first twenty years of flying were the exciting ones, although we should probably be told that modern aeronautics has its own thrills—but different ones.

Engineering structures are usually designed to minimise weight or some other cost criterion, subject to specified loading and functional conditions being met. The techniques of decision theory may be applied if the cost can be described mathematically in terms of the design variables. In particular, dynamic programming may be applicable to designs for which the parameter values can be derived sequentially. Dynamic programming is here introduced to obtain minimum weight layouts for two types of cantilever structure and comparisons are made with known Michell solutions. The results suggest that other near optimum configurations could be systematically derived under conditions less restrictive than those assumed by the Michell theory.

It is, I think, perhaps a remarkable thing that, unlike many inventions which require a general move forward over a wide field of achievement, at least one kind of flying, gliding and soaring, might have been achieved at any time in the past few thousand years. When, at the end of the last century, practical attempts were made it became apparent that effective control of heavier-than-air flying machines was a necessary requirement for its further progress. This was the problem that the Wright Brothers solved and made possible the development of aeroplanes.

My Boyhood in the 1880's covered a period when there was not much general interest in the possibility of mechanical flight. It was looked upon as a rather fanciful idea best left to Jules Verne. There was, however, plenty of evidence that the obstacles to achieving it were not fundamental but mainly quantitative. Cayley, Stringfellow and Henson had produced results which need not have discouraged other seekers of progress. Hargreaves was producing elastic-driven models and one could buy Chinese elastic-driven toy helicopters which flew well for under 1s.

As was said of Richard Trevithick, “Practical men are too apt to leave facts unrecorded”, and this is particularly true of those involved in the development of Britain's aircraft engine industry.

The names of a few people come to mind immediately, but there are others whose contribution has played a crucial yet barely-recognised part in directing the overall trend. In addition there are many others who have filled lesser but vital roles as members of the teams led by the better-known pioneers.

Source-material on which to base an account of the work of Society members is scanty, since the great majority of published papers have preserved that strict anonymity which is indicative of British “team spirit”.

There can be little doubt that the rate of progress in the development of aviation which was achieved in the years between 1915 and 1918 has never been exceeded in any period since that time.

The few “flying machines” with which the Royal Flying Corps went to war in 1914 were of many types, of primitive design and unreliable, having little relevance to war with the possible exception of reconnaissance duties. In 1914 there was no aircraft industry worthy of the name. The potential value of aircraft was only beginning to be fully realised by the middle of 1915.