In considering the necessity for requirements to establish the airworthiness of helicopters it is essential to take into account the capabilities of the vehicle itself, the environment in which the vehicle is likely to be used and the abilities of the people most likely to be involved with the vehicle.

As envisaged by the inventors the helicopter is a vehicle which is capable of both vertical and translational flight. Unfortunately if the helicopter enters a cloud whilst engaged in vertical flight all visual reference is lost and the pilot is unable to correct any disturbance due to gustiness in the surrounding air. Conversely, if descending in vertical flight a situation can arise where the rotor develops a vortex ring and without forward speed the descent rate cannot be reduced until the helicopter hits the ground. It is therefore apparent that in flying the helicopter the pilot has to know its limitations and must be trained to handle the aircraft properly. Again in the course of flying the helicopter there is a probability that something will fail and if that probability is too high then such failures must be taken into account in assessing the airworthiness.

It is my privilege this evening to pay tribute to one of the truly great men of British Aviation—Mr. C. C. Walker—in the centenary year of his birth.

C. C. Walker was born in Highgate on 25th August 1877, and in his boyhood there was only a limited degree of general interest in the possibility of powered flight. Most people regarded it as a Jules Verne idea—what we should today call ‘Science Fiction’.

However, his interest was clearly aroused and he had an early appreciation that the problems were soluble. In his own Reminiscences of Fifty Years of Aviation published in the Society’s Centenary Journal, he recalls a ride in Maxim’s steam-driven multiplane in 1894 and it is on record that at the age of sixteen he lectured to a boys’ club on the subject of flying. What a pity that the text has not survived.

In reviewing industrial education, concentration has been given to the higher educational programmes; also to courses in manufacturing technology and production management which include topics normally within the responsibility of the Director of Manufacture, as outlined in Fig. 1.

There is a wide range of programmes offered in the above topics at both undergraduate and postgraduate level.

For the undergraduate stream there are seventeen universities and polytechnics which offer first degree courses under a variety of titles such as: Production Engineering, Industrial Engineering, Manufacturing Systems Engineering, and some add Management to the titles as illustrated in Fig. 2.

Most universities and polytechnics have adopted the 4-year sandwich system as offering the most suitable blend of academic and industrial experience for graduates entering manufacturing industry. A very important part of the sandwich course is programming the industrial phase, and in recent years difficulties have been encountered in finding firms which are prepared to undertake this responsibility.

I suppose that I ought to start off by denning the who, what, when, where and how in the approved military report manner, because my experience has been in the aircraft design and development business and deals with the sharp end of the operation—i.e.—where it all starts. It is important for those who have not had experience in this area to be quite clear that we are dealing with a particular type of human being whose efforts, or the output from them, are difficult to plan or predict effectively. Tending to introspection for long periods, he is very conscious of the fact that, being at the beginning of the process, his errors multiply in costs down the line and this outlook leads to a marked reluctance to produce anything but the perfect. Naturally, this attitude can percolate down to the design support groups whose work is normally of a mechanical nature and quantifiable.

The issue that I have been asked to deal with is the contribution that could be made to improving motivation and productivity in British industry by developing the quality and effectiveness of supervision. This seems to require four things: a general discussion of the ‘problem’ of supervision; an examination of the main characteristics of supervisory systems in British manufacturing; a review of some recent attempts to develop the supervisory function and a set of conclusions pointing out alternative policies which seem to be required.

The idea that supervision is ineffective and conservative was argued by Frederick Taylor and others some 70 years ago and has been repeated by management specialists ever since. His remedy in Shop Management was to propose greater specialisation of control functions at shop floor level and the abolition of ‘general foreman’ positions. Such an approach was built on the argument that supervision was too weak and could not cope with the number and range of problems encountered in running a workshop or production system. His ideas led to the development of specialist functional departments, particularly for planning, industrial engineering and quality control; they did not lead to the abolition of the foreman role, although the scope of responsibilities within that role was greatly reduced.

British trade unions were the first to protect the interests of working people because it was Britain that had pioneered industrial development. Most unions were based primarily on craft to begin with. They were an extension of the old guild system, and entrance into them required a long apprenticeship but conferred considerable benefits in terms of security and status. Many of them had complicated and often idealistic constitutions such as the Engineers Union with its democratic checks and balances based on the philosophy of Rousseau. In fact these early unions were designed as much to protect the workers in them against other workers as to take on the role of social organisations resisting unfair employers.

The large unions for manual workers came later as more and more working class people abandoned the land and fled to the factories. These unions were more embracing, less concerned about qualification and often survive today with essentially the same constitution and rule books of their original founders. The main role of these unions quickly became the alleviation of the lot of working people at a time when the worst type of industrial boss practised the survival of the fittest, while often the weak went to the wall.

Most spacecraft attitude control systems employing mass-expulsion techniques use some form of pulse modulation at the output from the control system to the gas control valves. In a number of early designs such modulation was introduced almost accidentally by surrounding simple relay-type switching logic with a feedback loop containing a first-order lag to provide ‘derived rate’ damping. This arrangement gives pulse width and pulse frequency modulation (Combined pulse modulation).

Such a modulation scheme was devised by Schaefer in 1962 which he called a Pulse Ratio Modulator (PRM). His main concern was the mechanisation of the quasistatic equations of the modulator and he did not investigate the stability of systems containing a PRM.

In the production of aluminium alloy components, costs of rectification of distortion after heat treatment can become inordinately high, especially if those components are either large or of complex shape. With small parts of simple shape, the problem is avoided by forming in the solution-treated condition so that no further heat treatment is required, the principal limitation being that the forming must be completed within about two hours of heat treatment, otherwise the subsequent age-hardening process will be too far advanced. For more complex shapes, forming in the annealed condition is much easier, and indeed may be the only practicable procedure if a rubber press is to be used. Obviously pressing the components is generally quicker and more economical than manual forming. The problem that arises after forming—manual or press—in the annealed condition is that the components must then be solution treated, during which a water quenching operation can cause distortion, calling for the rectification previously mentioned.

The self-correcting wind tunnel has attracted considerable interest in recent years as a concept for achieving minimum wall interference in a wind tunnel. Sears, et al., have presented an authoritative account which is recommended to the reader. Among their important conclusions is that a perforated wind tunnel wall (with control of the pressures in subdivided plenum chambers) is superior to control of impermeable, flexible walls such as suggested by Chevallier and Goodyer. In Reference 2 and 3 and the discussion in Reference 1 it is assumed that the impermeable, flexible wall is deformed into an a priori determined shape of fixed magnitude. The selection of wall shape function and its magnitude is made so as to minimise wind tunnel wall interference. In the present paper this concept is broadened to allow at least the magnitude of the wall shape to vary with flow conditions, e.g. flow dynamic pressure. More generally the shape function might vary as well. As will be shown there are advantages to such a compliant wall concept.