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Smiths Industries is to supply the head‐up display system for the Sea Harrier. The company will design, develop and make the electronic head‐up display and weapon aiming computer system for the latest version of the HS Harrier which will operate from Royal Navy ships.

THE first gas turbine engines with digital control are now entering service, replacing hydromechanical controls which still control the large majority of engines, reliably and effectively.

Accles & Pollock Ltd. of Oldbury, Worcestershire, a TI Steel Tube Division company, will be exhibiting a comprehensive range of precision steel tube and tubular products, including plain, annularly convoluted and thin wall tube, at Farnborough.

Aeronautical & General Instruments Ltd, will exhibit their R 128 recording cameras, designed to photograph the information displayed on the cathode ray tube of an aircraft's reconnaissance radar.

The background of missile costs is discussed. Missiles are new and very costly. Developments in this field have been subjected to political vicissitudes which have often upset long‐term developments. Missile technology is on the frontier of science and there is no background of knowledge to draw on; much basic and expensive research is required. Missile engineering models are complex in detail and assembly, and therefore costly, and constant change occurs while making and testing the model. The complexity and functional requirements of missile parts are running a parallel race with the machines and processes being developed to fabricate the materials required. The usually small runs required in missile production again add to costs. Imposed on all these activities is the requirement that reliability of near 100 per cent is needed and in no case can reliability be allowed to be secondary to cost. The inflight life and shelf conditions for a missile are usually fairly well established and 100 per cent reliability for a short operating life with a long shelf life are the real requirements. There is a considerable tendency to overdesign for reliability. Some costly features of design such as finest finish, closest tolerances and highest strength are carried over by habit from aircraft design and are not always required in missiles. Having examined some causes of high costs, a programme for cost reduction is set out. Costs can be reduced by: (i) earlier freezing of designs making changes only in groups of several changes at wider intervals, (ii) making a more realistic approach to reliability designs, (iii) selecting tolerances in a more analytical manner according to individual needs, (iv) selecting materials on the basis of actual design requirements instead of using the very best materials available even when the short life makes them unnecessary, (v) avoiding tool‐room methods in production engineering, (vi) setting work standards on as many operations as possible and enforcing them to the greatest degree possible, (vii) selecting the best type of workers to make the transition from development models to production missiles as smooth as possible, and (viii) setting up rigid systems and parts designation procedures for handling production parts. Finally, methods of organizing research and development and production for bridging the gap between engineering design and production are proposed.

In this paper, with the goal of reducing the fuel consumption of UAV, the engine performance optimization is studied and on the basis of aircraft/engine integrated control, the minimum fuel consumption optimization method of engine given thrust is proposed. In the case of keeping the given thrust of the engine unchanged, the main fuel flow of the engine without being connected to the afterburner is optimally controlled so as to minimize the fuel consumption.

In this study, the reference model real-time optimization control method is adopted. The engine reference model uses a nonlinear real-time mathematical model of a certain engine component method. The quasi-Newton method is adopted in the optimization algorithm. According to the optimization variable nozzle area, the turbine drop-pressure ratio corresponding to the optimized nozzle area is calculated, which is superimposed with the difference of the drop-pressure ratio of the conventional control plan and output to the conventional nozzle controller of the engine. The nozzle area is controlled by the conventional nozzle controller.

The engine real-time minimum fuel consumption optimization control method studied in this study can significantly reduce the engine fuel consumption rate under a given thrust. At the work point, this is a low-altitude large Mach work point, which is relatively close to the edge of the flight envelope. Before turning on the optimization controller, the fuel consumption is 0.8124 kg/s. After turning on the optimization controller, you can see that the fuel supply has decreased by about 4%. At this time, the speed of the high-pressure rotor is about 94% and the temperature after the turbine can remain stable all the time.

The optimal control method of minimum fuel consumption for the given thrust of UAV is proposed in this paper and the optimal control is carried out for the nozzle area of the engine. At the same time, a method is proposed to indirectly control the nozzle area by changing the turbine pressure ratio. The relevant UAV and its power plant designers and developers may consider the results of this study to reach a feasible solution to reduce the fuel consumption of UAV.

Fuel consumption optimization can save fuel consumption during aircraft cruising, increase the economy of commercial aircraft and improve the combat radius of military aircraft. With the increasingly wide application of UAVs in military and civilian fields, the demand for energy-saving and emission reduction will promote the UAV industry to improve the awareness of environmental protection and reduce the cost of UAV use and operation.

THE period of 40 years since man first flew with the aid of an internal combustion engine has seen many changes in aircraft power units. Power has increased to an astonishing extent, yet reliability has also been obtained. Unfortunately, however, the amount of skill and knowledge required to obtain the best results from an engine can hardly be said to have decreased.

Electronic engine controls manufactured by Dowty & Smiths Industries Controls Ltd. (DSIC) have already completed more than 171 million flying hours. This includes experience gained by Concorde using a full authority electronic analogue system. The advent of microprocessor technology has now brought the benefits of digital control within the grasp of all military and civil engine manufacturers.

Condition monitoring and health management of an aircraft engine is of importance due to engine’s critical position in aircraft. Missions require uninterrupted and safer conditions during the flight or taxi operations. Hence, the deviations, abnormal situations or failures have to be under control. This paper aims to propose a cascade connected approach for an aircraft engine fault tolerant control.

The cascade connected structure includes a full-order unknown input observer for fault detection and eliminating the unknown disturbance effect on system, a generalized observer scheme for fault isolation and a Boolean logic mechanism for decision-making in reconfiguration process, respectively. This combination is simulated on a linear turbojet engine model in case of unknown input disturbance and under various sensor failure scenarios.

The simulation results show that the suggested fault detection isolation reconfiguration (FDIR) approach works effectively for multiple sensor failures with various amplitudes.

Different from other studies, the proposed model is sensitive to unknown input disturbance and failures that have unknown amplitudes. One another notable feature of suggested FDIR approach is adaptability of structure against multiple sensor failures. Here, it is assumed that only a single fault is to be detected and isolated at a time. The simulation results show that the proposed structure can be suggested for linear models especially for physical redundancy-based real-time applications easily, quickly and effectively.