Eight years ago, Dr. S. G. Hooker and M. Michel Garnier gave the 17th Louis Blériot Lecture on the same subject under the title “Power for Supersonic Flight”. Between then and now the airlines and the manufacturers have jointly evolved the new practices of health monitoring and modular maintenance, and have also made significant advances in both the basic safety of the design and the safety-monitoring of the functioning engine. More important still, the operators and manufacturers have become fully conscious of, and determined to respond constructively to, the growing public pressure to reduce pollution and technological nuisances of all kinds. Within the same eight years a complete new generation of civil engines, the large high bypass ratio turbofan, has been conceived, developed and has begun to operate in airline service. It incorporates many of the new concepts mentioned above, as well as reflecting the general progress in technology that has taken place in that time.

The continued trend of increased weight and landing speeds of modern aircraft has strengthened the demand for improved materials for the manufacture of aircraft brakes.

The aircraft brake is similar to the car disc brake since both represent a medium for the conversion of kinetic energy to heat energy by means of friction. There are, however, unique problems which confront the aircraft brake designer since he is required to provide an acceptable mechanism involving components of minimum weight. The present paper discusses some general aspects of aircraft brakes and deals in more detail with some of the materials and material requirements for aircraft brakes; in particular it is hoped to show the manner in which advanced materials can provide some answers to the problems of the most recent development in design.

If air racing history is reviewed, it will be seen that the peak was reached when British light aircraft manufacturing was supreme. In 1927 alone, there were no fewer than 81 records set. The resurgence of interest following the Second World War declined until 1963 when only three records were set. Since then, air racing has progressed in one form or another to recent times when the Trans-Atlantic air race produced many new records. Unfortunately, this type of air race does little for the sporting aircraft enthusiast, and since the last Schneider Trophy Race, 40 years ago, there has not been a major international air race where aircraft have been pitted against each other to determine which flew the fastest.

The motion of liquid in the containers of a vehicle may have severe influence upon the stability of the vehicle. For this reason many authors have investigated the behaviour of liquid with a free surface due to various modes of excitation. In the earlier development of small vehicles, the frequencies of the elastic structures were relatively high compared to the propellant frequencies and the effect of their interaction could be neglected. With the increase of modern space vehicles this interaction of the propellant with the elastic structure is becoming a pronounced influence upon the design of the vehicle and its control system. This has some influence upon the stability and response behaviour of a large space vehicle, since the close grouping of propellant sloshing and structural frequencies around the control frequency of the vehicle creates continuous interaction during flight.

When a continuum is represented in lumped terms as a set of nodes which are regularly connected in a specified sense, the state of stress at each interior node may be inferred from the forces which act on it. These ideas require some extension for plates and shells, whose flexure and twisting is basically governed by the Love-Kirchhoff hypothesis. The latter requires that the mid-plane stresses be combined with bending and torsional stress couples acting on interfaces perpendicular to the mid-plane.

The inflation of a parachute encompasses problems of aerodynamics, dynamics, and elasticity. The most noticeable effects of the interaction of the events are the opening force and the filling time. Attempts to analyse the opening process and to predict the opening force date back to 1927. Since then a considerable number of methods have been published. Some of them are primarily analytical, others more empirical, and several deal with isolated problems. The earliest and most analytically oriented studies are by Scheube and O'Hara.