The Sixteenth British Commonwealth Lecture, The Story of Indian Air Transport, by Mr. J. R. D. Tata, Chairman of Air-India International, was given before a distinguished audience on 18th November 1960 at the Institution of Mechanical Engineers, Birdcage Walk, London, S.W.1.

The President of the Society, Dr. E. S. Moult, C.B.E., B.Sc., F.R.Ae.S., M.I.Mech.E., presided at the meeting. Before introducing the Lecturer the President explained that hitherto the election of Fellows had been initiated by the Council and announced once a year but, under the new By-Laws, Fellowship was to be regarded as a position which could be attained by any qualified member who had reached a position of eminence and responsibility in the profession of aeronautics. At the same time it had been decided that the announcement of such elections should be made not just once a year, but on occasions such as this.

The names of 22 members who had been elected to Fellowship since May 1960 were then read out by the Secretary. (These names were published in the December Journal–Ed.)

After congratulating the new Fellows, Dr. Moult said that the British Commonwealth series of lectures started at the end of the War in 1945, and had continued annually until the present day. Throughout the years they had had a series of outstanding lectures on subjects associated with aeronautics in the Commonwealth, given by most distinguished lecturers. The stature of this lecture was set for all time in 1954 when His Royal Highness The Duke of Edinburgh addressed them on “Aviation and the Development of Remote Areas”. Now they were to hear about the growth of aviation in one of the great members of the Commonwealth. Air Transport in India was now thirty years old1 and there was no one more suited to tell the story of that thirty years than their lecturer, Mr. J. R. D. Tata.

Mr. Tata had been actively associated with this development all his working life. Indeed, it was true to say he had had a major part in it. He learned to fly in 1929 and personally flew the first scheduled transport service in India in 1932. He had been associated with aviation throughout all these years and a few years ago was president of I.A.T.A., the International Air Transport Association; he was now Chairman of Air-India International. He had great pleasure in asking Mr. Tata to give the Sixteenth British Commonwealth Lecture, “The Story of Indian Air Transport.”

The design of structures for operation at increasingly higher temperatures and under exposure to severe heating requires more detailed and more exact analysis to determine the most severe conditions under which a given structure is operationally effective. To meet this need, the following analysis has been devised, with the determination of stresses and deflections in plates due to non-uniform heating as its purpose. The analysis results also in the determination of the maximum loads which may be imposed on the supporting members by the plate due to its thermal deformations.

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.

The lecture theatre has now been opened, and I have taken it on myself to be the first to give an address in this newly-opened Theatre. I think this occasion is opportune to tell you something of its history and, in so doing, to demonstrate some of its facilities.

For many years the Council of our Society has considered the possibility of the Society having a Lecture Theatre of its own. Many of our Past-Presidents and Councils have expressed the desire and have made explorations but, though the wish was there, we did not see the means. Recent increases in the activities of the Society, the creation of Sections and Groups, each with its own Lecture Programme, added a new emphasis. Moreover, the problem of the hiring of halls has become increasingly difficult when one remembers that the Programme in London alone now includes more than 60 lectures.

It is reasonable to date the prehistory of the Helicopter Association from the arrival in this country of Juan de la Cierva in 1925, at the invitation of lames Weir and his Associates.

The helicopter idea had intrigued designers from the earliest days of aeronautical experiment but, so far, often to their detriment and the derision of their contemporaries. Cierva had been first in translating the theory of auto-rotation into practical terms and had proved that both stability and control in flight could be achieved regardless of forward air speed. The freely rotating rotor system of the Cierva Autogiro and other early gyroplanes, such as those of Kay and Hafner, provided the missing link which all had been seeking and from this point development proceeded by logical rapid sequence to the flight of the first potentially safe and controllable helicopter in Germany in 1937.

This note derives an approximate, theoretical formula for the tension rivet loads transmitted by a shear-buckled skin to the supporting stringers. Allowance is made for the influence of the in-plane stiffness of the stringers and frames in reducing the magnitude of the shear buckles. The formula will be most reliable in the range 1·5 <τ/τcr< 3. When τ/τcr<1·5 the effect of initial irregularities is important, though the rivet loads are not high. When τ/τcr>3 the effect of change of buckle pattern, neglected in this simplified treatment, becomes important. The analysis could however be extended to deal with varying buckle pattern.

In presenting this paper I shall take but a brief look at a rather interesting subject, the impact of which, on our business in aviation, has doubtlessly touched each and everyone of us. I refer to the subject of Cabotage—an old term which like so many others in human affairs has taken on a new meaning in a world shrunken by our own specialised activity of aviation.

Cabotage in its original maritime usage referred to carriage between two places within a geographical unit by earthbound vehicles. The essence of this cabotage however, was its parochial as opposed to international application and this was based on the recognised right of a State to reserve such carriage to its own ships. This restrictive nature of cabotage in maritime law is an exception to the general rule of the freedom of the seas.