I greatly appreciate the invitation to give the Handley Page Memorial Lecture. It has not been easy to select a reasonably suitable subject not already covered by some distinguished lecturer and I hope you will not think the subject I have chosen is too far removed from HP's interests.

I do not think it is: for he was a great practical engineer and a keen supporter of Cranfield in its early days. I doubt whether he had much time for academics except at Cranfield and maybe not for graduates even of engineering, for he had learnt his trade in a hard school and was justly proud of it. But times have changed, and just as the aircraft he designed changed to meet new markets and take advantage of advancing technology, so I think he would have approved of the new Cranfield Institute of Technology which has developed out of the old Cranfield College of Aeronautics, and particularly the Institute's very practical approach to teaching and research, and its close ties with industry from which it draws over 60% of its income.

Sir George Cayley (1773–1857), a remarkable 19th century scientist, was the first to formulate the principle of powered flight when in 1809 he stated in .his paper ‘On Aerial Navigation’: ‘To make a surface support a given weight by the application of power to the resistance of the air’. More specifically, Cayley must be considered the founder of the science of aerodynamics, while also being the first to design and build and successfully fly gliders, thereby inaugurating the concept of the modern fixed-wing aircraft controlled by elevator and rudder.

Recent developments in constant frequency alternating current (ac) generating systems for aircraft have realised substantial increases in power-to-weight ratio and potential reduction in cost-of-ownership.

Essentially this has been achieved by employment of maximum synchronous generator speed, refinement and corresponding advantage of hydromechanical variable-ratio transmission technology and a more highly integrated configuration.

Each of these aspects has required an innovative philosophy and extensive testing to bring the technology to a point where such equipment can be confidently specified for the next generation of aircraft.

You have honoured me and my associates in asking me to present your Sir Henry Royce Memorial Lecture. When I saw the list of my predecessors, and their contributions to aviation, I must say I have joined a very select company and can only hope that I shall be able to justify your faith.

When I first selected my title, I was not aware that the ‘Well Tempered’ description had been used previously by Arthur Raymond in his 1951 Wilbur Wright Memorial Lecture to the Royal Aeronautical Society. With sincere apologies to Mr Raymond, who was for many years responsible for engineering leadership of the Douglas Company, the selection of ‘Well Tempered’, which he derived from Johann Sebastian Bach, still seems most appropriate. I hope he will forgive me for using it again.

First, it is necessary to define productivity and the way it is measured. Productivity is a ratio of an output to an input; it is, therefore, somewhat analogous to the engineering concept of efficiency but unfortunately without the accompanying rigour of definition of input and output in energy terms. In productivity measurement, the output can be in value terms, in weight or volume or number, while the input can be numbers of men, man hours, wages or capital or some combination of these. These points are illustrated in Fig. 1, but in this paper I will be concentrating mainly on value outputs and manpower and labour cost inputs. A fuller account of the subject is contained in Ref. 1.

Materials science is continually advancing and the aim of this paper is to consider briefly the current state of the art on flexible and rigid materials and methods of selection to assist in the optimisation of material usage in airship construction. Generally the selection of materials for airship construction involves a compromise between the ultimately desirable and the economically attainable. However recent advances in composite material technology have broadened the range and versatility of materials available so that selections can be made which offer the prospect of safe airships with useful payloads at economic costs. It is necessary to consider flexible and rigid materials separately as their function and selection criteria differ substantially.

The College of Aeronautics performs an annual group project as a major part of its Aircraft Design MSc programme. Projects are chosen to be representative of current areas of interest and the programme carried out in a manner which is as close as possible to that of aircraft manufacturers.

The chosen projects alternate annually between civil and military types to give breadth to the course. It was decided that an executive jet would be a suitable subject for examination and a market study was performed. The small capacity end of the market was served by such aircraft as Learjets and medium capacity by BAe 125s and Citations. The top end of the market was of more interest because suitable aircraft could also perform other roles. The main reason for this was that market pressure for unrestricted headroom pointed towards larger diameter fuselages which could also be used for commuter aircraft.

What is Shuttle? In a word, it is a system for saying ‘yes’ to all passenger demand. It is the antithesis of the traditional airline product (invented, strangely, by a nautical man called Noah in Old Testament times) whereby demand is deliberately constrained to fit the capacity which the carrier wishes to offer. In the case of Shuttle, the level of production is dictated by market size on the day. It is the customer, not the airline, who calls up the back-up aircraft. Demand is not inhibited — so much so that the Eastern Air Shuttle in the United States is used as ‘the barometer of national prosperity’, according to Aviation Week magazine (15th October 1979 issue). As the word ‘shuttle’ is loosely used in a variety of countries and contexts — from weaving implements to Space Shuttles — I must give the product exact definition. The British Airways version is the same as that operated by Eastern Airlines in the United States since 1961.

Early work on mini-RPVs in the former British Aircraft Corporation, Guided Weapons Division was described in a paper presented at the symposium on ‘RPVs — Roles and Technology’ held at the Royal Aeronautical Society, London in January 1976. Since then research and development work has expanded in several areas.

Significantly, the Stabileye research RPV which in prototype form had made some limited flights at that time has been developed into a payload carrying RPV system for research and development work within the UK UMA Systems Research programme.

The main runway on the aerodrome at the Royal Aircraft Establishment in Farnborough, Hampshire, occupies land that at the turn of the century was always known as Laffan's Plain.

From this plain in 1908, S. F. Cody had made the first aeroplane flight in the British Isles. Four years later two subalterns of the Royal Flying Corps, a Corps that had been fathered by the Corps of Royal Engineers, were walking across this same land. As they walked, the officers discussed the choice of a motto for the Royal Flying Corps, for its Commanding Officer had sent out a general call for proposals. One of the subalterns, J. S. Yule, proposed a Latin tag that had been used by Sir Rider Haggard in his book People of the Mist. That proposal was, ‘Per Ardua ad Astra’, the motto of the Royal Flying Corps and later of the Royal Air Force. It has a supreme advantage among mottoes that all Latinists seem to agree that it cannot be translated! But at least most interpret it as ‘Through struggles to the stars’; and that is the theme of this paper.

Some interest was aroused in the middle of the eighteenth century when an Italian visitor to London exhibited a colourful flying machine which he promised to demonstrate. A full but comparatively little known report was published by the triweekly Whitehall Evening-Post in the issue dated 3rd-5th October 1751. Soon after its appearance, another Italian plagiarised it, sending a translation to a friend in Italy in the form of a letter, dated 18th October 1751, which purports to be an eye-witness account. This may have been published in Venice in the same year, as a fly sheet. In 1752 the letter and the flying machine were mentioned in a collection of noteworthy events, and in 1753 it was given cursory attention by Clemente Baroni Cavalcabò, in his famous book about the inability of demons to carry men through the air, The celebrated art historian Francesco Milizia included a brief summary in his biography of Paolo Guidotti, the painter and would-be aeronaut, and more recently the plagiarised text has been noticed by Italian historians of aviation.

With drastic increases in oil prices fresh in our memories, with a world recession in full swing, and with two Middle-East countries at war, this is not an auspicious time to speak about the future of civil aviation. But I am following an excellent precedent. In 1940, in circumstances of unrelieved gloom, Dr. Roxbee Cox, now Lord Kings Norton, addressed this Society on ‘Looking Forward’. His lecture was a message of confidence in the long term future of civil aviation, fully justified by later events. Though the energy threat is barely comparable with the state of affairs in 1940, its potential is very serious.

I am wholly confident that aviation can once again rise to the occasion. But this by itself is a small part of a big picture. We need to be satisfied that the world will cope sufficiently well with the energy situation that our future way of life will not be so impoverished that flying becomes an unjustifiable luxury.

Any aero engine designer works against a background of a list of general desirable features for all engines of:

In the helicopter business however, the engine designer is faced with a real dilemma. On the one hand there is the desire to produce an engine which has as wide an application as possible, (i.e. turboshaft, turboprop, turbofan, APU, industrial power generator, marine traction etc) and this produces a basically low cost, high volume, production flow provided that the required changes in the engine configuration are kept to a minimum.

I would in the first place express my appreciation of the honour conferred upon me by the invitation to deliver the J. D. North memorial lecture, on a subject with which I have been engaged for the past 37 years.

The subject is very wide, covering many types of pumps, and to do it full justice would require far more space and time than can be covered in a single paper. I have therefore attempted to bring out the reasons why we followed certain paths and the problems which caused significant design changes. If I appear to have given undue prominence to the work of the Lucas team, and made insufficient mention of the work of others, I would ask their forgiveness. The pumps used for reheat have been omitted as they are in a field of their own. The future may see a drawing together of the engine and reheat pump practices, although it is too soon to make a meaningful presentation, an indication of the most likely path is shown.

This paper presents first, a brief background relating the experiences and projections of Bell Helicopter Textron, to establish credibility and an understanding of the application of engines to rotorcraft; second, a discussion of helicopter powerplant and installation requirements, starting with some fundamentals of the engine size selection process and proceeding to point out some real, but often unspecified features that are needed; third, the potential of the application of advanced technology to the powerplant and to other areas of the rotorcraft; and finally the impact of the combined technologies on future rotorcraft.

It is surprising that, in a country with long and strong traditions in aeronautical engineering and naval architecture, the interactions between these two professions have only been sporadic and largely informal. There have been some notable exceptions, of course, such as the airship story of the 1920s (and its revival of interest in very recent times); hovercraft development; and on the educational front events such as the creation of a Ship Science group within the Department of Aeronautics and Astronautics at Southampton University in 1968. But unlike France, with its Association Technique Maritime et Aéronautique, and USA, with its regular joint meetings of the Society of Naval Architects and Marine Engineers with the American Institute of Aeronautics and Astronautics, collaboration between our two ‘Royal’ institutions has been negligible.

The surprising sequence of recent world political events and changes of government attitude have focused attention on our current state of armaments, readiness, and future intention in the fields of national and NATO defence. This affords an ideal opportunity for a discussion on that vital part of our national capability, the conventional armament of our aircraft. While this is a field which may not always receive the attention applied to other, more technologically glamorous areas, it is one which is playing a progressively greater role in the current and future defence scenario. Developments along this route have changed particularly rapidly during the past few years, and seem set to do so for a decade to come.

The 757–200, which started its development in 1974, will fly for the first time early in 1982. When this aircraft enters airline service in January 1983, it will set new standards for quiet, fuel-efficient operation. The roots of the current 757 configuration go back to the 727–300 study programme. The design evolution proceeded through the 7N7 study programme which lasted from early 1976 through 1977, and developed into the 757–200 now in production (Fig. 1).

It is possible, and even probable, that the next generation of defensive missiles will use modern methods of optimal control of the interception trajectory. Miniaturised computing is becoming so readily available that it becomes feasible to compute the optimal trajectory to the interception point.

Consider a ground site, defended by a surface-to-air missile, which is being attacked by a low-level intruder aircraft. As soon as the intruder is attacked, by launching the defensive missile, the intruder attempts to avoid interception by using evasive tactics; the intruder becomes the evader and the defensive missile the pursuer. When both the pursuer and evader use optimal tactics, the one to achieve interception and the other to avoid it, the result becomes the outcome of a game of pursuit and evasion, as described by Isaacs in Reference 1.

A successful project outcome requires that the ‘right’ product, (from an overall ‘performance’ viewpoint), should be available when the market place needs it, for a price it is prepared to pay.

To satisfy ‘performance’ requirements, (in the widest sense), the task is broken down into manageable elements, and requirements/specifications are formulated. As the design/development proceeds, progress towards achievement is monitored, with eventual verification through ground and flight testing. On ‘timescale’, we develop inter-locking ‘line of balance’ programmes covering all manufacture inputs, such that the effects on total programme achievement of local gains or shortfalls can be seen.