The 1,179th Main Lecture to be given before the Society–and the first Main Lecture to be given in the new Lecture Theatre–“Ten Economic Lessons from Short-Haul Airline Operations,” was given by Mr. S. F. Wheatcroft, B.Sc.(Econ.), A.F.R.Ae.S., on 15th December 1960. Mr. P. G. Masefield, M.A.(Eng.), F.R.Ae.S., Hon.F.I.A.S., Immediate Past President, presided.

Before introducing the Lecturer, Mr. Masefield said ttiat this was an auspicious occasion because this was the first Main Society Lecture to be held in the Lecture Theatre. Although he was sure there was nobody better fitted than Steve Wheatcroft to give this first lecture and no more valuable subject than the economic lessons from short-haul airline operations, Mr. Wheatcroft unfortunately had let the side down by not requiring any of the modern pushbutton equipment which was a feature of the Lecture Theatre.

Steve Wheatcroft was known to everybody in air transport, not only in this country but all over the world, where he spent half his time when he was not advising B.E.A. on what not to do. Mr. Wheatcroft obtained his B.Sc. degree with first class honours in economics at the London School of Economics in 1942. After the war, during which he served as a pilot in the Fleet Air Arm, he returned to the London School of Economics, taking a Leverhulme Post Graduate Studentship and studying, in particular, the economics of air transport. He was appointed Economic Adviser to British European Airways in 1946 and subsequently joined the Commercial Department as Manager in charge of Research and Tariffs. In 1953 he left the Corporation to go to Manchester University as a Simon Research Fellow and wrote a book called “The Economics of European Air Transport”. Wheatcroft on “The Economics of European Air Transport” was still a standard and was rapidly becoming a classic work. Since 1954 he had acted as a Consultant and had been retained as Economic Adviser to British European Airways. In 1958 he was commissioned by the Canadian Government to make a study of the desirability and economic consequences of trans-continental competition and his report, “Air Competition in Canada,” was published in June 1958. In 1959 he was appointed Chairman of a Committee set up by the Government of India to investigate the cost structure of the Indian Airline Corporation. More recently he had been a member of the Tymms Committee to the West Indian Government to advise on civil air policy in the West Indies, and now, he was about to go to Nigeria to tell them how to do it.

The history of the Agena space vehicle starts in the years immediately following the Second World War, when the Rand Corporation under a contract with the U.S. Air Force examined the potential applications of satellites, recognising their technical feasibility as an additional bonus from an inter-continental ballistic missile development programme. The U.S. Air Force kept this concept alive throughout the development phase of the ICBM programme; the Lockheed Aircraft Corporation actually received its first contract, for detailed engineering studies, in 1955. The Agena space vehicle has grown from these beginnings and is now the vehicle selected for a large variety of U.S. space projects. Most of these are satellites, but they include a few space probes and moon explorers.

Skylark is an upper atmosphere rocket designed to carry a payload of 150 lb. to a height of 100 miles. The project was the outcome of discussions between the Royal Society and the Ministry of Supply which started in 1953 and were completed in 1955 when Treasury approval was given for a joint Royal Society-Ministry of Supply programme of upper atmosphere research using a vehicle to be designed by the Royal Aircraft Establishment. The programme was the responsibility of the Gassiot Committee of the Royal Society, matters of detail being agreed at a working party and endorsed by the Gassiot Rocket Sub-committee.

The Short SCI V.T.O.L. Research Aircraft, using four special Rolls-Royce RB.108 jet lift engines, which made its first flights in 1959 heralds a new method of taking-off and landing which may revolutionise the operational flexibility of aircraft of the future. The Short SC. 1 is the result of six years research and development by Short Brothers and Harland Ltd., who built and developed the aircraft, and Rolls-Royce Ltd. who designed and developed the special light weight turbojet engines which support the aircraft during the V.T.O.L. phase and which are shut down as soon as the aircraft has attained wing borne flight by the horizontal thrust from its separate propulsion engine. The SC. 1 is shown in hovering flight in Fig. 1.

An aspect of structural design which is becoming increasingly more important is the behaviour of a structure when it is subjected to random pressure loading. Random pressure fields can be encountered in several different ways, two of the principal sources of such fields being the noise emitted by a jet, and the fluctuating pressures in a turbulent boundary layer. Many jet-propelled aircraft have suffered secondary structure fatigue failures in those parts of their structures near to the jet stream, and it is not unlikely that certain failures of panelling in engine intakes have arisen because of vibrations set up by the turbulent pressure fluctuations in the boundary layers at the walls.

A summary is given of some of the more important experimental results relating to the noise radiated from a cold subsonic turbulent jet. These are then related to the predictions of Lighthill's general theory of aerodynamic noise.

My first illustration Fig. 1 shows how the World's very first powered flight was announced in this Country—and it had no more notice in any other—I cannot help feeling that the first manned space flight will cause a slightly greater fuss.

I suppose it really all began, so far as my urge to fly was concerned, in the summer of 1910. At that time I owned half a 166 ton schooner—the owner of the other half was my old friend Bill Eyre.

Incidentally, the engineer in charge of the auxiliary engine was Fred Sigrist. We were to remain in partnership through many varied experiences in aviation for the following 30 years.

We had left Le Havre and as we were becalmed in the Channel we put into Dover Harbour. There we heard that an American architect of Spanish descent, Johnny Moisant, was flying a Bleriot monoplane (Fig. 2) in a field nearby so we thought we would go and have a look.

While the subject of this paper is concerned with problems somewhat outside the scope of those which existed in the days of the late Roy Chadwick, nothing absorbed Chadwick's interest more than a seemingly intangible aircraft problem, and I am sure that had he been alive today he would have been deeply involved in the search for solutions to them.

He was without doubt a man of great talent, with an intuitive flair for design, and I join the many members of his staff who deem it a great privilege to have been associated with him for many years; and am honoured to have been asked to present this Memorial Lecture.

Few things have given me greater satisfaction than the invitation to give the Seventh Barnwell Memorial Lecture, and tell the story of the early history of the Bristol Engine Department.

The Bristol Aeroplane Company which was founded by that great merchant venturer and pioneer of transport, Sir George White, has just passed its 50th Anniversary. I always look upon the 20 odd years spent with the Bristol Company as among some of the happiest and most stimulating in my engineering career.

With increasing speeds of aircraft, problems arise over materials of construction, partly through kinetic heating effects which cause temperature rises and partly through rain erosion effects. Additionally, account has to be taken of a required life of 30,000 hours which is much longer than that over which most materials are normally evaluated.

For speeds of Mach 2.2, the maximum temperature attained will be of the order of 130°C, while for Mach 2.7 the corresponding temperature will be 200°C or higher. For the lower speed, it is probable that aluminium alloys will be satisfactory, although it must be emphasised that no information is yet available on the long-term behaviour of materials at the elevated temperatures likely to be experienced. Test programmes are in hand, but these will necessarily take considerable time for their completion. For speeds of Mach 2.7 or above, steel or titanium alloys will be required, but here again the necessary evaluation for long periods at high temperature has yet to be completed.

The invitation for this lecture requested “a review of missile structures from the viewpoint of an aircraft designer.” This is inevitable because most of the author’s experience has been associated with aircraft design. There are however many people actively concerned with missiles who have had considerable experience designing aircraft and would be better qualified to make a more realistic approach to the subject. The difficulty for an outsider making a review of missiles is justifying the “need to know” and then, having found out, or deduced interesting facts, he may be made aware that to publish them would contravene some security ruling.

I shall try to set the Air Traffic Control scene by describing how the responsibilities of States to provide Air Traffic Services are currently exercised in the United Kingdom, and by indicating some of the measures being taken to ensure that these services keep pace with the increasing demands of the air space users. Any opinions I may express are, of course, my own, and do not necessarily reflect the views of the Ministry of Aviation.

If man's desire to fly was not totally inspired by the flight of birds at least his early attempts at heavier-than-air flight were a direct imitation of birds. To the earliest known aviators two features seemed indispensable in any flying machine, wings that flapped, and wings covered with feathers. The former at least seems reasonable, but no attempt was made to discover the purpose of feathering a bird's wing and feathers were used simply to give the flying contraption the appearance of a bird. As we shall see later these factors probably delayed the advent of sustained flight—not necessarily powered—by many years.

Imagination has always, in the past, attributed the bird with greater powers than it really possessed. Many early flying machines were designed as chariots borne by as few as six doves—powerful indeed! Its powers to soar so high that it became lost to sight gave it the status of a semi-deity, from which came the mariner's faith in the albatross, perhaps.

When South Africa joined the Commonwealth Advisory Aeronautical Research Council in 1948 it was decided that the study of atmospheric turbulence was the first research project which could be undertaken. Equipment for the recording of aircraft accelerations was not then available commercially so an apparatus was assembled in the laboratory of the National Physical Research Laboratory, use being made of a commercial sensing head and an oscillograph galvanometer with photographic recording. The apparatus weighed about fifteen pounds so it was used on Douglas DC-3 (Dakota) aircraft which were flying for the S. A. Air Force on routes from Pretoria, to Durban, Cape Town and return. This apparatus recorded altitude and vertical acceleration of the aircraft. At a later date a lightweight commercial instrument was purchased and fitted into a Douglas DC-4 (Skymaster) aircraft flying on the routes of S. A. Airways. This instrument recorded altitude, air speed, and vertical acceleration.

Today we are Interested in the scope of the research programme rather than the actual details of the physics. Further I shall discuss space research rather than just upper atmosphere research, because we include astronomy and this will be discussed by others as well.

Now I have, in fact, a formidable task, because I find I have something like twenty-three experiments to deal with in twenty minutes. What I am going to do therefore is to list the experiments that are going on, to tell you whether they have been carried out successfully, or are awaiting completion, and thus to try to give you some idea of the scope of the work which has been undertaken.

“ God bless the Duke of Argyll!”

In the Lecture Hall at Hamilton Place, London, of the oldest aeronautical society in the world, that Duke of Argyll, who became its first President in 1866, looks silently down upon those members who, less than a century later, succeeded so noisily to fly faster than the sounds of their own triumphant cries of success.

A description is given of the distribution of vorticity in the surface of thin wings with large leading edge sweep. Although the delta wing is chosen as the basic plan form the deductions are general and applicable to other types of wing. The conclusions are illustrated with experimental evidence from a water tunnel.

The tailless aircraft configuration is relatively rare in the field of aircraft design and for many years was regarded as a “freak” design. It is intended to trace the development of tailless and flying wing aircraft and to outline the major problems in control and stability.

First it is necessary to arrive at an arbitrary definition of the term tailless aircraft. Later an attempt will be made to classify the different tailless types in detail, but for the moment it is sufficient to regard a tailless aircraft as “an aircraft having no auxiliary horizontal stabilising plane, deriving lift and controlling moment solely from the main plane.” This definition, as it stands, includes what are often termed flying wing aircraft.

A solid propellant rocket motor consists essentially of a propellant charge in a container fitted with an expansion nozzle and igniter. Since, before a rocket motor can be designed, it is necessary to have some knowledge of the properties of the propellant to be used, a description will first be given of the propellants which are currently available.