Strictly many materials such as ceramics, cement and even metals should be classed as polymers since the atoms within them are bound by strong chemical bonds into large groups usually of indefinite size. This article will deal only with the synthetic organic polymers and, in fact, will consider mainly the plastics, little attention being given to rubbers and fibres.

The industrial production of synthetic plastics has expanded greatly in the post-war years largely using petroleum as the starting material. The plastics produced do not have good mechanical properties compared, say, to metals and have other limitations such as poor resistance to heat and inflammability.

The establishment of an Industry Training Board for the civil air transport industry in March 1967 provided, for the first time, a single central point of focus for the trained manpower needs of the Industry. The early months of the Board's existence were preoccupied with the establishment of its own internal administration, with the search for accommodation, and with the recruitment and selection of staff. These internal matters were largely disposed of by April 1968, and since then the Board has started to fulfil its proper function.

In this lecture I intend to talk about two treaties adopted under the auspices of the General Assembly of the United Nations. To give them their full titles, they are the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space including the Moon and other Celestial Bodies and the Agreement on the Rescue of Astronauts, the Return of Astronauts and the Return of Objects Launched into Outer Space. For convenience, I shall call them the Treaty on Outer Space and the Agreement on Rescue and Return.

One of the most interesting aspects of the aeronautical endeavours of Henson and Stringfellow was their awareness of the impact of the aeroplane as part of an overall transport system. It is all too easy in the field of aeronautical engineering to become mesmerised by the engineering intricacies of what one is doing and so fail to see the vehicle as part of this overall system concept.

In many respects we have, I think, been able to avoid this inward thinking in the helicopter since its vertical flight capability has become intimately bound up with considerations of its operational duties.

The first drawing showing a recognisable Harrier-type configuration was produced in the Project Office at Hawker Aircraft Limited, Kingston, in October 1957 (Fig. 1).

During the next year the design of this P1127 project was refined by detailed study and the final BE53 engine configuration was settled between the Hawker Team led by the late Sir Sydney Camm, and the Team at Bristol Aero Engines Ltdf led by Dr. S. G. Hooker. Hawker worked on a private venture basis and Bristol proceeded, on manufacture as well as design, with 75% backing from the USA by the Mutual Weapons Development Programme Agency in Paris.

If maximum gas temperatures aire to rise appreciably above 1500°K, the value currently achieved in advanced aero-engines, alternatives to the present internal convective methods of air-cooling the first-stage turbine blades will have to be sought. One of the most promising developments lies in the use of porous blade materials, through which cooling air can be “effused” or “transpired”. In a recent paper Bayley and Turner have shown that by the combination of high heat transfer coefficients within the interstices of the porous material, and a reduction in heat transfer rate by injection into the boundary layer on the hot-gas side of the blade, effective cooling rates can be achieved.

The instrument described here is designed to measure mean flow directions and velocities in the three-dimensional boundary layer. Its particular advantage is the small amount of interference it introduces, while allowing measurements to be made close to the surface and providing an acceptably large traverse distance normal to it. In its present form it is restricted, however, to flat surfaces where space beneath the surface is not at a premium.

When a hovercraft travels at forward speed, the change in ambient pressure due to the airflow around the vehicle affects the forces experienced by the air cushion and hence, the static and dynamic stability of the vehicle. Such changes are likely to be especially important for a tracked hovercraft entering, or operating within, a tunnel. Knowledge of their magnitude is important in determining the smallest, and hence cheapest, acceptable tunnel.

It is a great honour, and of considerable personal pleasure to me, to be asked to give this lecture—pleasurable for a number of reasons.

First, this is a unique occasion: this is the first time that a serving officer of the RAF has been asked to give the Sir Henry Royce Memorial Lecture and it is most appropriate that this should coincide with the 50th Anniversary Year of the RAF.

Secondly, I have always taken a great interest in aeroengines, with which I have been closely associated throughout my service career as both pilot and engineer. My early apprentice training was done on the Rolls-Royce Condor engine.

Projections of future trends in any field must be somewhat subjective; this assessment of future research on rotorcraft is no exception. However, an effort has been made at objectivity by presenting results of past and current research efforts as a foundation from which the projections are made. These projected trends are solely the opinion of the author and do not represent the policy of any agency within Government or industry, nor are they committal in any sense. Although some illustrations are derived from specific systems under investigation, the general intent of the paper is to avoid discussion of systems and to present illustrations representative of basic problems in the field of rotorcraft for which research effort can be expected to yield significant advance in performance and design.