As in many other branches of engineering, progress in propulsion controls has, for the past 30 years, meant the increasing application of electronics.

Throughout this period, the whole Aero-Engine Industry has used electronics to perform various limiting functions, particularly in the form of jet-pipe temperature limiters. However, Rolls-Royce and the British Controls Industry are undoubtedly the pioneers in the radical application of electronic technology to the control of aero gas turbines. World-wide, there are still only two aero engines in civil operation today with ‘Full-Authority’ electronic controls. They are:

The Rolls-Royce Proteus turboprop which has accumulated seven million hours in the Britannia since its entry into service in 1957. Its pre-transistor Ultra system still uses magnetic amplifiers and has achieved a very high reliability indeed, (in-flight shut-down rate = four per million engine hours).

Noel Penny Turbines Ltd (NPT) is progressively extending its family of low cost turbojet and turboshaft engines for application to unmanned vehicle systems (UVS). The family now incorporates eight distinct engine types, spanning a jet range of 50 to 1200 Ibf sea level static thrust and a turboprop/ turboshaft range of 15 to 450 SHP. The scope of these basic engines enables a wide variety of application and installational requirements to be covered. The crucial first target is low manufacturing cost.

The object of this paper is to introduce this UVS engine family and highlight highly significant design and development features necessary to meet both operational requirements and low cost.

An understanding of the market and the way it is likely to change with time is central to the planning of any business enterprise. Forecasting in air transport is particularly difficult because of the number of factors which influence the potential market (political, economic, social, environmental and technological) and because demand itself is very much influenced by the range of prices and qualities offered to the consumer. The lecture will review the purpose of forecasting and then examine the techniques of forecasting that are available in order to assess their usefulness in airline planning.

The preparation of a forecast is not an end in itself: rather it should be an essential and central element of the business activity. It should be part of the systematic search for opportunities and an aid to giving an overall direction to a business enterprise. For these reasons, forecasting should be seen as part of the mainstream of the planning activity and should not be left to isolated individuals in ‘backwater’ departments. Part of its value is in the formal evaluation of market intelligence and the understanding of the forces which are at work in the market place. Much of the benefit of a forecasting exercise will be lost if the ‘intelligence’ it generates is not diffused into the rest of the organisation. Similarly, line departments need to be involved in the forecasting process to help forecasters avoid ‘wishful thinking’ and pure ‘star gazing'.

The prospect of reducing the induced drag of an aircraft by using both a canard and tailplane for trimming is investigated and results are compared with those for conventional tail-aft and canard arrangements. It is concluded that improvements of approximately 20% in lift-drag ratio are theoretically possible at high lift coefficients by the use of an additional trimming surface.

The objectives of the first flight of Spacelab (to be launched in September 1983) are to verify the Spacelab performance and to demonstrate its use as a tool for experimentation in a variety of scientific and technical disciplines. The latter objective will be achieved by the operation of a joint ESA-NASA payload wherein about 50% of the available resources are allocated to the complements of each Agency. The total payload amounts to 2785 kg and consumes about 2 kW of power. The configuration chosen for the first mission (orbital inclination 57°, altitude 250 km, duration nine days) is a long module plus one pallet and some 70 experiments will be on-board.

The paper describes the total payload but particular attention is given to the European portion — FSLP (First Spacelab Payload). The scientific objectives of the mission are presented and representative experiments from the various disciplines (Atmospheric Physics, Earth Observations, Material Sciences, Plasma Physics, Astronomy and Solar Physics, Life Sciences and Technology) are described. The tasks associated with check-out and integration of the individual experiments and their related software into the FSLP are explained and the associated ground operations and flight operations planning portrayed. In the latter context, the Tracking and Data Relay Satellite System (TDRSS) and the Payload Operations Control Center (POCC) play an important part. The role of the on-board crew is stressed and the general advantages of man-in-the-loop are discussed.

Finally, some of the complex management inter faces are illustrated and the paper explains how this challenge has been met. It is concluded that the considerable experience gained from this international joint venture into manned space flight must be retained for the optimum fulfilment of future European man-tended space experimentation.

Within the past few years, there has been a growing interest in the utilisation of airships for a variety of missions. Studies funded by NASA and the US Navy have shown that modern airships not only could perform certain tasks more economically and silently than other aeronautical vehicles (short-haul passenger and freight transport, and long-duration ocean patrol), but that they could perform unique missions, such as the V/STOL transportation of bulky loads an order of magnitude beyond helicopter capability.

The types of modern airships envisioned fall into two categories: modernised blimps and heavy-load carriers. Blimps are receiving reconsideration for their traditional role of patrol and surveillance because of their fuel efficiency and the development of modern sensing devices which require a quiet, stationary vehicle for deployment.

The Directory attempts to list all heavier-than-air flying machines, whether models or of man-carrying size, which are said to have been built and tested in western Europe prior to the Montgolfiers. While I do not include machines which are known to have been totally imaginary, I have been fairly liberal in my sifting of the evidence. Thus the list includes items ranging from those about which there is no historical doubt whatever (eg, the ornithopters of Blanchard) to others which may never in fact have existed (eg, the zany structure conceived by d'Alcripe's drunken Norman labourer).

To the layman the parachute is often no more than a large pocket handkerchief which brings men safely to earth without a bump, but to the aeronautical engineer it is a complex aerodynamic decelerator, which has a large number of degrees of freedom and dynamic characteristics which are often difficult to account for by classical aerodynamic theory. Whichever view one may care to take of the parachute what is certain is that advances in parachute technology are nearly always the result of a balanced programme of both theoretical and experimental work, and for this reason equal attention will be given in this paper to both the experimental and theoretical aspects of parachute technology.

Ladies and Gentlemen, tonight we pay homage to Frederick William Lanchester, Doctor of Laws, Fellow of the Royal Society who, having become interested in mechanical flight at the age of 21, while studying at South Kensington in 1889, entered the field of aeronautics in 1892 and continued to aid its development until his death in 1946. His great contributions to aeronautics were the discovery of the theory of the vortex motion of the lifting wing and that the key to successful flight lay in reducing the skin friction, which was far from being the negligible quantity that others such as Langley, whose name is forever remembered through NASA Langley Field, had stated earlier. All this was in 1893 to 1894 some ten years before the first flight of the Wright brothers. When asked later how he had successfully derived his great and momentous theory Lanchester simply stated; ‘it was a matter of logical deduction helped by experiment’. He vigorously defended his work as not being empirical but was soundly based on hydrodynamic theory.

The arrival on the aeronautical scene of a new generation of propeller driven commercial aircraft, and the great interest in the propeller as an economical means of propulsion for high subsonic Mach numbers, makes this an appropriate time to look back and attempt to identify some of the evolutionary paths by which the present state of development has been reached.

A consideration of the history of the propeller may be confined to the period beginning around the late eighteenth and early nineteenth century, when the propeller was clearly recognisable as such and becoming established. However, the idea goes back many centuries before this and there is a wealth of references describing, not always very precisely, various mechanical devices intended or actually used for ship propulsion which may be considered remote but legitimate ancestors of the present day propeller. Before considering more recent developments, it is worth looking at the beginnings of mechanical propulsion if only to pay tribute to those early engineers who did not allow the lack of suitable materials or theory to inhibit their attempts.

The topic of testability in equipment appears to generate as many different views as people asked to express an opinion. Certainly, a manufacturer's perceptive of testability appears to vary from the equipment user view. Both will agree that testability is an essential characteristic of equipment but its need is driven by different requirements. This paper presents a view of testability as seen by the users of complex military equipment in the three services. The general thesis is that the testability needs of the Royal Navy, Army and Royal Air Force must receive greater attention than at present given and that each element of the Armed Forces is faced with maintaining equipment for 20 years or more whereas industry has a much shorter period of interest.

In developing this thesis the paper starts by discussing the military requirements for testability and outlining the maintenance philosophies adopted by the three services. Procedures for establishing an effective testability programme, as part of the overall design effort, are then considered and a possible technique for the numerical assessment of testability is mentioned. Finally the paper emphasises the importance the three Services attach to the transportability of test software.

Bonus schemes have tended to fall into disrepute and have been neglected; this is a pity because they are an extremely powerful tool when applied successfully. One of the weakest areas of the individual bonus scheme for cost control was the setting of standards through individual negotiation influenced by many factors, rather than by estimating the work content.

During 1975, the individual bonus scheme was suspended at British Aerospace Weybridge-Bristol Division, Filton Site, and a start was made on the development of a cost control system based on work measurement and using modern computing techniques. The new system had to contain two essential features. First, the speedy identification of jobs giving problems on the shop floor, since it was realised that the suspension of the individual bonus scheme would slow down this process, secondly the provision of a fast and reliable method of checking the work issued to the shops against the original estimates.

Digital data transmission techniques enable various elements within a system to communicate in an efficient manner. Multiplexing techniques permit this data to be transferred rapidly, accurately and reliably, without the constraints imposed by conventional wiring systems which employ heavy and costly cable runs and expensive connectors. In today’s cost conscious aviation world, both military and civil users are anxious to capitalise upon savings in cost and weight while gaining substantial benefits in terms of performance and reliability.

Smiths Industries has been involved for over a decade in the application of multiplexed data transmission systems. The military Tornado serial data transmission system and the civil ARINC data transmission systems are areas where specific expertise has been established. More recently the weapon systems unit of the company’s Cheltenham Division together with Micro Circuit Engineering, an SI subsidiary, has established a world lead in the development and the application of the widely accepted data bus standard, MIL-STD-1553B.

This Memorandum describes the development of a laboratory prototype true air speed sensor for use on unmanned aircraft. The sensor works on vortex shedding principles and has a digital output. The vortices are sensed by thick film thermistor elements that are non-critical in the signal circuitry.

The development of the jet engine produced jet noise problems. Most of the understanding of jet noise was and is performed in universities. The fundamental and quite exceptional work of Lighthill was followed by that of Curie. Powell and Ffowcs Williams at Southampton in the early 1950s and was paralleled by experimental investigations on noise suppression by for example. Lilley at Cranfield. This university work was used to form the basis of a programme of research into jet engine noise at Ministry of Aviation establishments with considerable university inputs which established a commanding lead for the United Kingdom in the understanding of jet noise.

The formation of the Institute of Sound and Vibration Research at the University of Southampton under the inspiration of Professor E. J. Richards was a step which placed university research at a different level to that usually observed in the United Kingdom by concentrating in one place some 40-50 people all devoted to research and postgraduate education.

The unique aerodynamic features of the highly coned propeller, with cyclic and collective control of blade pitch, are discussed in simplistic terms.

The configuration poses severe structural design problems and, while fibre reinforced composites fabrication might enable these to be surmounted, there will be weight penalties in overcoming them that will limit potential applications.

No outstanding prospect for the propeller is identified, but specialised applications may merit a closer scrutiny of the concept.

The latest generation of commercial jet transports, typified by the Boeing 757 and 767, is improved over prior generations by the widespread application of new technologies. For example, weight is being reduced by selective use of composite materials, by utilisation of stronger alloys in the structure, and by employment of computer-aided design and manufacturing techniques. Aerodynamic advances in wing design are reducing drag, lowering fuel burn, and allowing higher cruise altitudes. A new generation of engines are providing significant improvements in fuel consumption and noise suppression. But perhaps the most significant of the new technologies, is the extensive utilisation of digital computation in this latest generation of commercial transports.

There is a history of criticism from aircraft operators, both civil and military, regarding the poor reliability of fuel associated systems, especially gauging, and the high pilot workloads that can result when a malfunction occurs during flight of light strike aircraft. In response the Ministry of Defence (Procurement Executive) sponsored work, initially at Smiths Industries and later at British Aerospace to investigate improved gauging and fuel management using digital concepts. It is concluded from flight trials that digital gauging will provide increased accuracy over a range of aircraft attitudes and with greater reliability than current analogue systems. Further, in a military aircraft, there are many advantages in a microprocessor based fuel management system which integrates fuel measurement, transfer and warning functions. These include reduced pilot workload, higher system integrity, fault detection, and system reconfiguration following battle damage. The evolutionary process leads naturally towards consideration of the inclusion of the fuel system functions in the centralised management of all the utility systems, based on Def Stan 00-18 data bus. Practical investigations of microcomputer based fuel and other utility systems are required to ensure that their full potential is realised within the limits imposed by the need for cost effective solutions.

As military aircraft become more multi-role in design, the use of externally carried ordnance has increased both in frequency and variety resulting in increased use of wind tunnels for store load measurement. It is intended that this report may be useful in predicting loads on a variety of isolated stores at speeds up to transonic and in providing loading data on a new store carried on an aircraft by converting wind-tunnel measurements made on an existing store.

The estimation of aerodynamic loads uses linear methods for forebody and fin-wing normal forces with cross-flow terms on body and fin and also tail recovery effects represented by higher-order predictions. Allowance is made for body to lifting surface and lifting surface to body carry-over effects. The effect of the location of the fins and wings with respect to the body and their dihedral is also accounted for in the prediction.

Fleet planning is a complex process. Undertaking it is time consuming as, properly conducted, it involves virtually every part of the airline organisation in a series of sub-analyses all of which impact on each other in some way. Parts of the process are deeply technical but others may be purely subjective relying on the intuition or judgement of the airline’s one expert in the particular field.

Obviously in fleet planning we have to investigate suitable types of aircraft. Most of the factors involved are fairly well known. Their ability, or otherwise, to operate our routes economically and without significant restriction is vitally important as is our ability to maintain them in service. We need to understand our markets and the factors which influence passengers to travel in the first place, and with us rather than our competitors in the second.