A new controller design method of lateral-directional dynamics is proposed. This method is based on the formulated pilot model, and the controller is designed so that the pilot-aeroplane system attains the desired requirements. Robust stabilities and handling qualities can be taken into account. The proposed method was applied to B747 dynamics, and flight simulator experiments were performed, and the designed controller was verified.

The impact point dispersion of mortar missiles can be drastically reduced with a control ring of lateral pulse jets located around the centre of gravity and a homing head to measure or to derive estimates of appropriate missile-target states, e.g. the line-of-sight rates. A simulation model including a missile as a six-degree-of-freedom vehicle, a jet pulse flight control system, and a relative missile-to-target motion was used for the comparison of four guidance laws i.e. proportional navigation guidance, augmented proportional navigation, augmented proportional navigation with rendezvous, and adaptive sliding-mode guidance. This paper focuses on the efficiency of pulse jet control on miss distance, and thus makes the assumption that sensor measurements and the guidance states required to apply each of the guidance laws are perfectly known. Proportional navigation and the adaptive sliding mode guidance exhibit a large miss distance due to limited control authority. Augmented proportional navigation is slightly better than augmented proportional navigation with rendezvous for the same design parameters and they both give small miss distances with limited control authority, but they both require a free gyro. A proper selection of the design parameters — the number of pulse jets and the magnitude of the individual pulse jet thrust for a particular dispersion of flight parameters and the instant of the guidance start — is required to achieve optimum dispersion reduction. The minimum intensity of the individual pulse jet impulse required for the ‘pin point’ accuracy (the circular error probable smaller than 1m) of the mortar missile was determined for all presented guidance laws considering dispersion from the nominal trajectory.

Aircraft full-scale fatigue tests are expensive and time-consuming to conduct but are a critical item on the certification path of any aircraft design or modification. This paper outlines a proposal that trades cycling hours for increased detail in the teardown of a metallic test article. A method for determining the equivalent demonstrated crack size (and crack growth curve) at the mandated test life utilising the lead crack framework is demonstrated. It is considered that the test duration can be significantly reduced, whilst still achieving all the desired outcomes of a certification program.

This paper investigates the impact of the wall-heating conditions on the heat transfer performance of a rotating channel with one side smooth and one side roughened by 45° inclined ribs. Previous experimental and numerical studies for single-ribbed wall-heated channels showed that rotation has a significant negative impact on heat transfer performance. In order to investigate this uncommon behaviour, RANS simulations were conducted under three different wall-heating conditions in the present study: ribbed wall heated, all walls heated and adiabatic conditions. Numerical results show that the presence of uneven wall-heating conditions has a negligible impact on the stationary case, but it has a large influence on rotational cases, in both, the heat transfer and the flow field. The underlying reason is that in rotating cases, uneven heating results in different buoyancy effects on the trailing and leading walls of the channel that alter the main flow velocity profile. As a consequence, also secondary flows and heat transfer performance are affected.

The fact that attention must be given to stiffness as well as strength in aeroplane design is now generally recognised. The provision of adequate strength alone is not sufficient to ensure that an aeroplane is immune from such troubles as flutter, loss of lateral control due to twisting of the wing and wing divergence. This is illustrated by the case of the Puss Moth. As shown in R. and M. 1645 this machine was examined in detail by the Aeronautical Research Committee and found to be completely satisfactory as far as the existing official airworthiness requirements were concerned, and yet it experienced failures which were attributed to flutter, an instability involving the stiffness of the wings and tail.

In the earlier stages of the investigations into these stiffness problems it appeared to many practical people that the work. was of academic interest only. As a matter of fact it was of subsidiary importance while operational speeds of aeroplanes were relatively low, but the higher speeds of the modern aeroplane make such problems of direct practical interest.

Experiments have been performed to study the influence of multiple surface static pressure tappings on transition of the boundary layer on a circular cylinder in cross-flow. A wide range of tapping and cylinder dimensions have been examined to demonstrate that the tappings can act in the same way as trip wires or other surface roughness to reduce the Reynolds number at which transition occurs. Hence, the pressure distribution around the cylinder may be influenced by the presence of the tappings, leading to incorrect measurements. Examination of the data has resulted in a correlation which should make it possible to avoid this tapping/boundary layer interaction in future experiments involving similar cylindrical bodies.

Vortices are of interest in many situations in fluid mechanics. One type of vortex with which the gas turbine designer is concerned is the line vortex springing like a miniature tornado from a point on the ground (or from a nearby aircraft surface) and entering the engine intake. It is possible for these vortices to suck stones up into the engine (Refs. 1, 2) and also to reduce the compressor surge margin (Refs. 3, 4). They are unsteady, in that their point of origin wanders about and so does their point of entry into the intake. This unsteadiness makes it very difficult to measure them, and so far no one known to the author has reported measurements of ground vortex strength, in the course of several investigations of the phenomenon (Refs. 1-3, 5-8).

A general review of the state-of-the-art in relation to stability augmentation in aircraft design, with an attempt to produce a co-ordinated view on the philosophy of its application, is something that I have long felt I should like to see done—but not by myself. My initial reaction on being asked to present such a paper was that this would better come from those concerned with the development of auto-control systems, but on second thoughts, there appeared to be some merit in considering the situation from the point of view of one concerned with the more basic aspects of aircraft handling and operation, putting the emphasis, therefore, on what is required or desirable in these respects, rather than on how it might be achieved. This, then, is my first aim; to consider various possible areas of application of stability augmentation, and advanced control techniques, to aircraft design; my survey will not attempt to be comprehensive but rather, selectively illustrative; it will, however, extend out beyond the confines of pure aircraft design, to externally guided aircraft flight, and in particular automatic landing.

In preparing this lecture I found it necessary, when considering recent changes in aircraft design, constantly to ask myself the question “Is this particular change due to airworthiness requirements or does it arise from reasons other than airworthiness?” In fact, one must consider whether requirements have any influence at all on the development of trends in design. Should design be likened to a runaway horse with requirements following some way behind, or are requirements a strict rein by which the pace and direction of design is controlled?

My own answer to these questions is that the pace at which development takes place is not influenced at all by airworthiness requirements, but that requirements help to prevent design from running off the path of safety. To carry the analogy a little farther, the faster the development is, the more difficult it is to keep it running on the path of safety.

The Plowden Committee has been considering ”… the future place and organisation of the Aircraft Industry in relation to the general economy of the country taking into account the demands of national defence, export prospects, the comparable industries of other countries, and the relationship of the Industry with Government activities in the aviation field.” Against this background of inquiry into the future structure of the Industry, it seems opportune to consider in some detail the actual process of mergers and reorganisation which occurred in the Aircraft Industry during the period 1957-60. This paper will attempt to explain the reasons for the mergers, the development of Government policy towards the Industry during this period, and the actual process of events which produced the recent industrial structure.

A survey is made in retrospect and prospect of the field of VTOL aircraft. The helicopter and the new VTOL aircraft, although historically separated and differing in appearance, belong to the same family of VTOL aircraft. The dominant parameter in this family is the disc loading, giving the two fundamental types of actuator disc—open disc or rotor and buried disc or fan. Noise and vibration criteria are discussed. The rotor is subject to fundamental aerodynamic limitations, which give speed limits for the pure rotor as well as the rotor compounded with a fixed wing. Rotors are subject to scale effects which limit the economic size of helicopters. Engine requirements for helicopters are discussed. There are three basic types of helicopter. Their characteristics, economics and uses are examined.

One of the novel problems presented by supersonic transports is the control of the complex powerplants needed to achieve optimum efficiency over a very wide range of forward speeds.

The subject is a large one and its proper understanding involves the disciplines of aerodynamics, thermodynamics, servo-theory and finally human engineering, because its end product is a set of knobs, levers, lights and dials which must be usable by the flight crew.

This paper is intended as an elementary introduction, using the special case of the Concorde as a basis. First, an attempt is made to give the aerodynamic and thermodynamic reasons for the large number of powerplant variables which the control systems must manipulate. On this basis, a functional specification of the control systems is established and, finally, the crew's job of propulsion management is described step-by-step in the course of a typical mission.

The past decade has seen considerable advance in the production of cotton from Rhodesia and the adjacent former Federation territories of Malawi and Zambia, brought about very largely by the introduction of effective pest control measures originating from the work of the Cotton Pest Research Scheme, located at Gatooma, Rhodesia.

Complementary to a work programme investigating the type and formulation of insecticides capable of controlling an insect pest complex including bollworms, jassids, aphids and stainers, attention has been given to the design of spray equipment suited to both extensive European and intensive African forms of cultivation. The “tailboom” modification to the conventional knapsack sprayer has been developed and this versatile piece of equipment in several mechanised guises forms the basis of the recommended ground spray machinery.

The title of this paper is “V.T.OX. and S.T.O.L. Aircraft and Helicopters and the System of Air Traffic Control they will require,” but it does not set out to give an audience of Air Traffic Control experts a lecture on how they will have to run their business in the future. What it does do is to make a few remarks on how the operators will wish to run these types of aircraft, when they have them, and to draw some inferences about the new problems in Air Traffic Control which will have to be solved as a result.

The solution has been obtained for the problem of a uniformly compressed and symmetrically loaded circular ring plate of linearly varying thickness. Four particular cases have been discussed and numerical values of the maximum deflection have been obtained for various sizes of the hole of the ring.

The first ten years following the end of the First World War saw a steady “run down” in the armed forces and during this period what still existed in the field of aero-engine development was inspired, mainly, by participation in long range pioneering flights, distance records and international speed events—such as the Schneider Trophy Contest.

Research and development were limited by the funds available and it was not until about 1935, when the Government decided on an “all out” policy to re-equip the Royal Air Force with equipment to match the growing aerial strength of Germany, that aero-engine development received the support it needed. It was somewhere in this period that marked the “renaissance” of the development of aero-engines.

Various liquid and gaseous alternative fuels have been proposed to replace the kerosene as aircraft fuel. Furthermore, new combustion technologies were developed to reduce the emissions of aero-engine. A staged fuel injection arrangement for a lean burn combustion system was applied to improve the operability of an aero-engine by achieving high flame stability at reduced combustion emissions. Originally, both circuits (pilot and main) are fuelled by kerosene; moreover, the pilot injector is operating at low power (engine idle and approach) and the pilot flame is anchored in an airflow recirculation zone. In the case of the performed research, the pilot injector was modified to allow the use of gaseous fuels. Thus, the burner model allows a flexible balancing of the mass flows for gaseous and liquid fuel. The present paper describes the investigation of ignitability for the proposed staged combustor model fuelled by gaseous and liquid fuels. A short overview on physical properties of used fuels is given. To investigate atomisation and ignition, different measurements systems were used. The effectiveness of two ignitor types (spark plug and laser ignitor) was analysed. The ignition performance of the combustor operating on various fuels was compared and discussed in detail.

Screen separations as little as 0.02 chamber diameters do not adversely affect suppression of mean-flow non-uniformity provided the overall pressure drop coefficient, K, does not exceed about 3.5. At larger K a velocity overshoot develops near the wall boundary layers, which decreases only slowly with wider separation. A simple approximate extension can be made to the theory of Taylor and Batchelor for any number of closely-spaced screens. This shows good agreement with measurements and with low-drag screens predicts perfect attenuation when the overall pressure-drop coefficient is 3.2 or 7.6. Some inferences regarding the effect of close screens on turbulence suppression are also drawn.