To ensure meaningful evaluation and prediction of configuration and flight effects on aircraft noise generation and propagation, reliable representation and measurement of relevant aerodynamic flow conditions as well as of acoustic characteristics must be possible. Acoustic wind tunnels, with models mounted in a quiet test section airstream surrounded by an anechoic working chamber, have now been established as primary tools for noise-model research work and should next be exploited also for the direct support of specific quiet aircraft projects. The special advantages of such tunnels in ensuring a more sheltered and controlled environment than outdoor mobile-model facilities and flight testing include capability of continuous operation, repeatable test conditions, high productivity, good measurement accuracy, testing flexibility, and the precise alleviation of reflections from neighbouring surfaces. Of course the recent experience on noise testing under forward speed conditions and on associated techniques is still very limited at both model scale and full scale, as compared with extensive and continuous aerodynamic testing over half a century. However, many of the problem areas associated with subsonic tunnel design and application for noise-model testing, as identified over five years ago, have now been clarified. Also, the special treatments or limitations involved have become quantifiable in many respects, as discussed later under the convenient main headings of tunnel test section requirements (section 2), tunnel circuit design (section 3), special measurement and analysis techniques (section 4) and model scale simulation (section 5).

Control is a fundamental part of the aeronautical sciences playing a necessary role in the design of all air-vehicles whether they are aircraft or balloons, missiles or kites. The early years of aircraft research were characterised by the amount of effort devoted to the control of the aircraft, and the shortcomings of early aircraft designs were frequently due to instability and to poor handling characteristics. Indeed the triumph of the Wright Brothers in 1903 when their first sustained powered flight was made at Kitty Hawk was due as much to their mastery of the problems of control as to their work on aerodynamics, structure or powerplant, vital though these latter were.

There are inherently two ways of obtaining an aircraft design having the desired control characteristics, either by so designing the structure and the aerodynamics of the aircraft itself or by providing some ‘artificial’ or ‘automatic’ control to change its characteristics. The latter method uses the signal from some sensor in essentially the same way that the human being uses signals from his vestibular organs to stabilise himself, and the crane fly similarly stabilises his flight using signals from his vestibular organs to stabilise himself, and the crane fly similarly stabilises his flight using signals from his halteres. The technique was tried even before 1903, and Sir Hiram Maxim in 1891 had produced a patent for an aircraft using a pendulous gyroscope for pitch stabilisation (Fig. 1). For various reasons most of these early efforts were rather unsuccessful, and in the period up to the Second World War the principal advances in the science of aircraft stability and control came largely from the refinement of the basic aerodynamics of the vehicle.

The first point which must be made—and I may not be the only speaker today who will make it—is that there is nothing new in a low air fares policy, at least so far as the United Kingdom is concerned. During the 1950s British independent airlines pioneered low fare scheduled services to Africa—the ‘colonial coach’ services. Much of the expansion in air travel that occurred between the United Kingdom and Europe and on the North Atlantic in the 1960s was due to the availability of low fares on charter services. Control over the minimum prices of inclusive tour holidays in Europe was finally suspended by the United Kingdom in 1972. In the same year, Edward Heath, addressing the Annual General Meeting of IATA in London, bluntly warned the scheduled airlines of the world that if they did not cater for the mass travel market by offering low fares, Governments would make sure that somebody else did. In the same year Laker Airways was licensed to operate a Skytrain service to New York—a scheduled service geared specifically to a low fares policy.

In the two and a half years that Concorde has been in service with British Airways and Air France, the nine aircraft in service have carried 250 000 passengers, travelled 16 million miles and accumulated 15 310 flying hours. These numbers, though still small by airliner standards, are sufficient for effective comparison of service experience with predictions made and objectives set during the design process. This provides the central theme of our paper.

The Concorde project, always controversial, has been assessed many many times on technical, economic and environmental grounds. In fact it has inspired a literature of its own, comprising papers of all kinds–favourable and unfavourable, learned and hysterical. It has been the subject of predictions by the hundreds, ranging from the optimistic to the absolutely dire. This paper, written with the benefit of hindsight, is thereby distinguished from the bulk of this literature.

One big problem found during the course of preparing this lecture, was the vastness of the subject. So there will probably be many things that should be said that will be left unsaid, but it is hoped that all the main factors have been considered at some point, even if they only get a passing mention. One point should be made, the freight and cargo market are not considered, as the majority of freight is carried in converted passenger aircraft or in the holds of passenger aircraft particularly in the large wide-body types. This trend seems likely to continue and it is unlikely that specialised freight aircraft will be developed for short haul operations.

The A300B aircraft is a co-operative effort by France, Germany, Great Britain, USA, Spain and the Netherlands. The work sharing regarding manufacture of the structure is as follows:

• MBB: Fuselage sections from the tail cone to section 16, upper shell of section 15, and the vertical tail.

• VFW-Fokker: Fuselage sections 13 and 14.

• AS: Flight compartment, fuselage sections 12, 15 (lower shell), wing centre box and pylons.

• CASA: Horizontal tail and passenger compartment door No 1.

• Fokker-VFW: Movable components on the wing, flap track fairings.

• British Aerospace (HSA): Cantilever wing, slats.

• General Electric: Engines.

• Messier: Landing gears.

The design of the A300B was based on many years’ experience gained on aircraft like the Trident (HSA) and the Caravelle (AS). Furthermore, by means of extensive studies and tests, bases were created to ensure reliability of the structure and to achieve an optimum design regarding weight and cost.

There has recently been evidence of an upsurge of activity in general aviation in the United Kingdom, particularly in small scheduled operations which are frequently referred to as ‘third level’. Much of the non-scheduled activity has been generated by North Sea exploration and the tendency for stronger ties with the European Economic Community (EEC). The recent growth in third level operations owes some of its impetus to each of these reasons, but there have also been moves to operate domestic links on routes which are not well served by the ground transport infrastructure. These include the Newquay-Gatwick and Norwich-Birmingham-Swansea-Newquay routes, the helicopter service between Fort William and Glasgow, the formation of Air Wales and Air Westward and the intention of British Caledonian to set up its own network of third level feeders for its international services at Gatwick.

The five-six seater single-engine helicopters represent a large share of the civil market. The market studies show that the main target to be reached in this field is to succeed in having a purchase price and operating costs significantly lower than those of current aircraft.

But the quality aspect of the helicopter should not be overlooked: the comfort and performance data should remain at a competitive level; the helicopter should have a high reliability level and offer easy maintenance characteristics.

Therefore the light advanced helicopter should represent an excellent cost efficiency compromise. This was the constant target kept in mind all along the design, development and production phases of the AS.350 (see Fig. 1).

The rapid rate at which the world's oil reserves are being used up, and the lack as yet of convenient substitute fuels at a competitive cost level, are leading to an increased emphasis on fuel economy in the design and operation of aircraft. This paper outlines technological advances that will contribute to the reduction of fuel consumption and attempts to give a broad indication of the overall improvements that may be achievable in relation to current technology. Since a companion paper is concerned specifically with work in the United States aimed at such objectives, attention is concentrated mainly on advances being made in the United Kingdom.

In this lecture I wish to cover:

• 1. What the Tornado is.

• 2. What the starting conditions for it were.

• 3. Overall formal management aspects.

• 4. Detailed and pragmatic aspects of management.

• 5. Achievement.

• 6. General remarks.

It is usual to say that views expressed are personal and do not necessarily represent those of the Companies concerned. This seems somewhat ironic to me, involved in international collaboration, where most statements of any definition do have international agreement, but reference in depth to my many colleagues on such a wide aspect has not been possible.

In recent years, there have been rapid advances in the development of theoretical methods in aerodynamics, particularly for transonic flow calculations. Many papers have been written on this topic. It is however appropriate that there should now be a paper that concentrates not so much on the methods themselves but on the use of the methods for computer-aided design. One could say that the most striking development in the UK in the past two-three years has been that the methods are no longer merely within the preserve of the research establishments; they are being actively used by the aircraft industry in the design of actual aircraft projects. Any air of scepticism about their value has been dispelled. The designers are now appreciating through their own experience that with the aid of a powerful computer and indeed in some cases, a computer of only modest capacity, they can specify a shape for the first wind tunnel model of a new project with much more confidence that the test results will show that the shape is near what is required to achieve their design objectives. It is already being claimed that in this way, the time-scale of the design cycle is being shortened considerably. Also, the computer and the theoretical methods are being used increasingly in the interpretation of the test data. The forecasting of the full-scale characteristics on the basis of the model test data is developing into more of a science and less of an art based on past experience.

It should be fairly obvious that, in contemplating the design of a future combat aircraft, it is important at the outset to relate the effort to some forecast definition of what is needed. This may take the form of an official or an unofficial requirement; however, its precise form is immaterial to the central argument. Either way, it is necessary to recognise several limitations to a so-called requirement:

1. i) the chances of it being ‘right’, some 10-20 years before the realisation of its potential wartime application, is fairly remote. This is particularly true with today’s rapid advancement in, for example, weapons and sensor technology. These developments make it doubly difficult to predict the nature and strength of the threat force;

2. ii) the postulated scenarios will change from day to day, and indeed, during the day–according to the course of the main battle; therefore the military commander's requirements of the forces at his disposal can change by the hour;

3. iii) the environment, both militarily and climatically, plays a large part in the definition of a design. The variability of the environment is neglected only with grave risk to the eventual utility of the weapon system.

The Light Aeroplane Group of the Royal Aeronautical Society was set up with the aim of encouraging activity in the light aeroplane field in Britain and its hope is that production of light aircraft should be restarted in this country. Clearly there are many problems to be faced in setting about the renaissance of an industry which will range far beyond the scope of those encountered in building a ‘one-off’ aeroplane. In this paper I shall present three case studies of light aircraft produced in the recent generation. I hope that this will give a reasonably complete picture of the implications of starting light aeroplane production and will therefore form a good basis for discussion.

In formulating the design competition which has just been announced, we have taken note of the market appraisal which Hugh Field presented at Cranfield in September 1977 in which he pointed out that there is still a lack of a really good training aeroplane in the world market and also of the specification that Alan Bramson has put forward for the so called Multi Role Club Aeroplane which is aimed at just that slot in the market. The results from Alan Bramson's survey of opinion from flying instructors showed the acceptability of a low-wing, tricycle undercarriage monoplane with side-by-side seating.

The MADGE aircraft approach aid is being supplied to Mobil for fitment to the Beryl ‘A’ Platform in the North Sea where multiple approach paths, offset in both azimuth and elevation are to be provided. Application has been made to the UK Civil Aviation Authority for approach limits of 150 ft (200 ft for Beryl ‘A’) Minimum Descent Altitude and 300 metres RVR equivalent.

MADGE was originally designed to meet a NATO requirement for a tactical approach aid which could be carried by two men, and set up in 15 minutes and give guidance to all aircraft types. This is a totally different application from the one at Beryl ‘A’ and yet it uses the standard MADGE production airborne equipment and standard MADGE production ground station units supplemented by ancillary ground equipment to provide offset tracks and monitoring facilities.

This last year has shown how delicate a balance exists between all constituent parts of our travel industry. Airlines, airports, air navigation, governments, travel trade, hoteliers, tourism institutions, aircraft manufacturers and above all, consumers have faced uncertainty and change. Most changes have been sudden, some have been successful, and others have proved difficult.

Main beneficiaries of recent relaxations in price and entry rules have, so far, been some scheduled airlines (through increased revenue) and some passengers (through lower fares). Airports, charter airlines, people living near airports, tourism institutions, even governments, have all shown less enthusiasm (especially at peak times).

It is a fact that there were many more sceptics and only a few advocates for the airship in the UK some ten years ago. Few people had given serious thought to the possible return of the airship as a modern transport form, still fewer were prepared to back it financially and it was left to the few to put forward their thoughts and plans for its return. In this they were encouraged by the small fleet of blimps being flown by Goodyear in the USA and by the fact that the US Navy had not phased out airships until 1962.

If one sees a satellite as being a remote sensing platform or as a communication path between two terminals on the Earth, one can appreciate that the spacecraft and its complementary ground infrastructure are essentially electronic devices handling data for the benefit of a ground-based investigator or user. As such, there is a space data-handling system which comprises an onboard and a ground segment. Both segments cover the functions of data collection, data distribution, data processing and storage, data encoding and decoding, timing and synchronisation of events, and data transmission and reception currently forming the well known telemetry data link and the telecommand data link (TTC).

The initial phase of the design of an aircraft is usually thought of as being glamorous and exciting since it is the part of the total exercise which determines those characteristics of the aircraft for all to see. The artistically inclined can let his imagination run away with him as he visualises an aesthetically pleasing concept. The inventor has more than ample scope to propose layout innovations which supposedly confer some advantages, often of ill defined value. Tradition has it that the renowned designers of the past with their vast experience, aesthetic flair and innovatory streak would blend all the numerous possibilities into a satisfying if not always entirely satisfactory, project.

Of course such an idea is a gross over-simplification of the project design process which, as in any design activity, must consist of many configuration iterations before an acceptable solution is achieved. The large number of variables which have to be considered coupled with the extremely demanding performance and safety requirements of any advanced aeronautical system imply such complexity that every aid available must be employed.

A new generation of helicopters was born at the beginning of the sixties, when, following a US requirement for a light observation helicopter (LOH), a new breed of military machines, like the Bell 206 (OH-4 A, OH-58 A), the Hiller 1100 (OH-5 A) and the Hughes 500 (OH-6 A) was developed.

All the aerodynamic and structural progress resulting from the previous experience of the helicopter industry was incorporated in their designs. The development of these helicopters, demonstrating good performance and comfort levels, light and relatively inexpensive was made possible, however, only because of the availability of a new, light turboshaft engine, featuring acceptable levels of fuel consumption and reliability.

In the past, it has been generally accepted internationally that in order to land aircraft in runway visual ranges below 400 metres—ICAO Category 3 conditions—a fail operational automatic landing system is required. The Trident aircraft with its triplex system is of course an example of this philosophy. However, the overall system requirements for such operations were specified nearly a decade ago and considerable advances have been made since then on such aspects as understanding fog characteristics, avionic system design, visual aids and of course, airline experience of all-weather operations. Consequently, there is now a world-wide interest in trying to ease the system requirements without jeopardising safety, for example, by considering the use of less complex fail-passive autopilots. If feasible, this would allow existing suitably equipped aircraft to operate to lower minima and hopefully, widen the spectrum of aircraft capable of being equipped, with overall benefits in terms of increased regularity and hence revenue.