The Royal Aeronautical Society has a history of 100 years. I can look back over a membership of more than half that time, since I was made a Fellow in 1911.

My start in the aeronautical world began in 1910. I was appointed Engineer in charge of Design at Farn-borough by its chief, Mervyn O'Gorman. He was a far-sighted and inspiring man, under whom it was a pleasure to work. The War Office had lost faith in aeroplanes and our work was to be confined to lighter-than-air craft. Sam Hiscocks was the able chief draughtsman of a very small drawing office with whose help we managed to make three airships. The latest was called the Delta, and had a speed of 45 miles an hour. This may seem absurdly slow but it was faster than many aeroplanes flying at the time. The Delta was eventually taken over by the Naval Air Service and was used for submarine spotting during the First World War.

In this paper we are restricting our attention to those cases of circumferential inlet distortion where the distortion of the velocity profile is too large to be described as a small perturbation. Thus any theory describing the flow must use a mathematical model which is non-linear.

I Would like to describe an approach which is being made by the Air Registration Board to the Safety of complex systems such as those used in automatic landing, or in supersonic and other advanced aircraft, since I believe that these methods may have a further application in the assessment of aircraft reliability.

Airworthiness Requirements can be considered to be of two kinds. There are empirical requirements based on engineering interpretation of past experience, and there are those which stem from a selected level of safety and which involve consideration of probability of occurrences. This paper is concerned with the second kind since it is relevant to the consideration of reliability.

The utilisation of high speed digital computers for structural analysis is commonplace in the aircraft industry. However, despite this, no information appears to exist which indicates, nationally or internationally, the degree of utilisation in the various companies.

In an effort to give some indication a world survey was undertaken.

During recent years, with the introduction of more complex aircraft structures, new techniques of aircraft servicing have been needed. It is essential to find even the smallest defects at a very early stage, but costly strip-examination must be avoided so far as possible.

Non-destructive testing is now playing an important part in this field, but many aeronautical engineers are unaware of the capabilities and limitations of the main methods.

This paper sets out to explain the basic principles of radiography, ultrasonic testing and eddy current testing. Since sampling inspections using these methods are now a mandatory requirement on all civil aircraft the paper should be of interest to all readers.

This paper represents the personal views of the author and the objectives do not necessarily form any part of current official thinking.

Sooner or later, Europe is going to accept that it must indulge in space exploration and subsequent exploitation if it is not to lose its position as a principal technical community. While it may be conceivable that exploration may be undertaken by “small scale” activities, it is certain that exploitation will require a substantially greater capacity to deploy men and materials in space. This paper demonstrates the approach we would make to the problem of transportation of such payloads, which will be a basic part of such a venture, and the philosophy which leads to this approach.

Having been asked to recount a brief history of the origin and conception of the Aeronautical Technical School Movement, I wish to pay the highest tribute to the philosophy, example, logical methods and encouragement of those men from whom I had the good fortune to receive my own training and under whom I was privileged to serve. Their sterling qualities were co-ordinated and embodied in the establishment of the first Civil Aeronautical Technical School and have led to the achievements of countless of its pupils.

The basic principles of the School have remained unaltered but they have been adapted and amplified, with success, to meet the requirements of subject, numbers, nationality, language, character, creed and environment, for a variety of projects for Governments and Industry, involving the training of individuals and small classes up to many thousands of trainees—maximum results in the minimum of time being the objective.

Exact expressions for deflection, swept volume and the ratio of the balancing force to the total thrust due to pressure are given for the case of a flat circular plate subjected to a uniform normal pressure and held fixed both in displacement and slope on the periphery and at an inner radius.

It was with some trepidation that I accepted the Society's invitation to contribute a Chapter to this Centenary issue. As the Lord Chancellor in Iolanthe has it,

“But though the compliment implied
Inflates me with legitimate pride,
It nevertheless can't be denied
That it has its inconvenient side.“

Nearly all those mentioned in the following chronicle of British achievements have known me personally; many have been my colleagues. It would be unfortunate if what I have said, or have failed to say, about their work were to disturb hitherto harmonious relations.

Maskell has developed a theory for the blockage effects of bluff bodies in a closed wind tunnel and has shown that it gives good results for flat plates normal to a stream. For streamline bodies there are well established methods of calculating the corrections, but for long bodies with blunt bases it is not obvious what method should be used.

“When I use a word”, Humpty Dumpty said in a rather scornful tone, “it means what I choose it to mean—neither more nor less.” Lewis Carroll's words could hardly be more appropriate than to the expression “Cost Reduction” as used by the businessman. To some, cost reduction appears as a game played with imaginary money to earn “brownie points” to please a customer. To some in organised labour, the words are viewed in the same generic class as “sweat shop” and “scab”. To others, however, cost reduction seemingly implies a business discipline exercised in earnest and to be reflected in the company balance sheet. The question then, may well be asked, “What is cost reduction?“—“Is it possible to provide a meaningful management technique to motivate cost reduction activities and to measure the results?“

I have been asked to express a user's viewpoint of what is required to ensure the adequate Reliability of military aircraft before their introduction into service, and to outline briefly what the Operational Requirements staff of the Royal Air Force are now doing to assist in this.

The problem of unreliability arises, particularly for military aircraft, from the increasingly complex systems which are needed to meet our stringent performance requirements. The reliability of equipment has not kept pace, and this has led to difficult and costly maintenance problems. These difficulties are further emphasised by tactical requirements which demand minimum maintenance in the field. The nature of STOL/VTOL operational aircraft and the need to deploy them with minimum support facilities is a special case where reliability is of outstanding importance.