bluuebunny/crossref_metadata_2025 huggingface dataset:
The Evaluation of Flutter Characteristics in Design
Authors: Shevloff N.P.
Published: November 2014

IT is commonly held that today we are living in the age of the specialist. Within the aircraft industry, no one is more vulnerable to having this label of specialist thrust upon him than the flutter and vibration engineer, but I submit that far from having the narrow outlook which is taken to be the specialist's chief property, the flutter man has to be part stressman and part aerodynamicist; he must also have a working knowledge of the application of electronics to modern vibration test techniques and computing machinery, to say nothing of being part mathematician and, not least, part engineer, for we must not forget that after all, strange as it may seem at times to some of us, in the calm of our design offices, we are engaged in the engineering business.
Energy Theorems and Structural Analysis
Authors: Argyris J.H. , Kelsey S.
Published: November 2014

This paper continues the theme of the opening Part I by analysing a number of problems designed to illustrate some particular aspects of the general theory. Three are concerned with thermal stresses and the last applies inter alia the theorems on maxima and minima to find lower and upper bounds to the St Venant torsional stiffness of a thin solid section.
Energy Theorems and Structural Analysis
Authors: Argyris J.H.
Published: November 2014

THE application of the general theory with displacements as unknowns to frameworks—both of the pin‐jointed and stiff‐jointed type—is straightforward. For the stiff‐jointed system the method is particularly simple when direct and shear deformations are ignored. In fact, for all frameworks the determination of the matrices C and C0 is trivial once we consider all possible degrees of freedom of the joints. See for example, the systems of figs. (23), (24) and (48) investigated on pp. 48, and 91, which show clearly how elementary the matrices a and stiffness k are when we break up the structure into its simplest constituent components. We need not therefore concern ourselves any more here with frameworks, and we turn our attention to the membrane type of system characteristic of aircraft applications. Essentially, a major aircraft structure like a wing consists of an assembly of plates (fields) stiffened by flanges along their edges. The field may be a curved and/or tapered surface but we ignore here both these effects and consider only rectangular flat elements of constant thickness. For convenience the element formed by the plate (sheet) and its fouredge members is denoted by the term unit panel. It is assumed that the flange areas are constant along each edge.
Pressure‐cabin Fatigue
Authors: Walker P.B.
Published: November 2014

INTEREST in the fatigue of cabins of transport aircraft has increased considerably in the last year or so. Fatigue tests on a complete aircraft, undertaken as part of the Comet accident investigation, gave indications that the fatigue life of pressure cabins could be more critical than had generally been supposed.
The Electronic Digital Computer in Aircraft Structural Analysis
Authors: Hunt P.M.
Published: November 2014

This paper describes the use of preset and programme parameters with the matrix interpretive scheme (which was considered in Part I) for the preparation of general purpose programmes for an electronic digital computer. The implications of partitioning the matrices when using the force method of analysis are considered in detail and the above techniques are applied to develop general purpose programmes for the calculations encountered when using this method of structural analysis. The general case, when all matrices are partitioned; the displacement method of structural analysis, and the use of magnetic tape storage, are considered in Part III.
Turbine Disks for Jet Propulsion Units
Authors: Johnson A.E.
Published: November 2014

In previous paragraphs of the paper, use has been made for various purposes of the results of investigations carried out for the Panel on a number of disk materials. In this section a detailed description of this work is given.
A Programme for Low Aspect Ratio Wing Analysis
Authors: Morton J.P.
Published: November 2014

AN important factor in the design of a modern high speed aircraft is the time taken to carry out an analysis of the wing structure. The modern tendency is to design wings which contain a large number of spars and ribs, thus giving rise to structural problems of high order redundancy.
The Creep Deflexion of Magnesium Alloy Struts
Authors: Johnson A.E. , Mathur V.D. , Henderson J.
Published: November 2014

This work was undertaken to examine the possibility of predicting the creep deflexion of magnesium alloy struts from tensile creep data. Creep deflexion tests on magnesium alloy struts at room temperature, under four loads, and lasting 1,000 hours, have been made and interpreted by the use of tensile creep test data for the same magnesium alloy. For strut deflexions small compared with length, and such that plane sections of the strut remain plane, it appears that the following assumptions arc reasonable: (i) during bending and compression creep of the strut similar relations exist between the stress, time and creep strain, as under conditions of simple tensile or compressive creep; and (ii) the rate of creep in any fibre of the strut is a function only of the current stress and time and not of the path by which the current conditions arc reached. These assumptions appear to lead to an average error in computed values of deflexion of an order which for practical purposes is small. It seems reasonably possible that the above mentioned assumptions may be expected to hold for struts of heat resistant material at elevated temperatures such as are met with in practice, provided that the order of deflexion is analogous to that occurring in the current tests, and the creep characteristics of the material are of a generally similar nature.
Honeycomb Sandwich Construction for Supersonic Aircraft
Authors: Noton Bryan R.
Published: November 2014

Sandwich construction with aluminium honeycomb cores bonded to faces with the adhesive films Redux 775, 775R and Bloomingdale FM‐47 is discussed. Drawings showing its applications to a series of components for various hypothetical aircraft arc included. Sandwich materials for supersonic aircraft of the types now entering production are reviewed, as well as the application techniques of the new Redux films. Some rules gathered from experience for the design of components with honeycomb cores, and solutions of special design problems with hypothetical wing panels, are treated. The paper then deals fairly fully with results from a programme of FFA investigations on this type of structure. The specimens discussed were bonded with Redux 775 and FM‐47 and consisted partly of tensile tests on cores, compressive tests on sandwich columns and shear tests on various sandwich webs. Design curves have been plotted in some cases. Further results are presented showing the influence of temperature on the shear strength of an aluminium alloy core and Redux 775 and FM‐47 films. Also a few creep results are given where the object of the tests has been to determine the optimum curing temperature and time for applying Redux 775 to yield minimum creep values. The room‐temperature results illustrate the excellent properties of honeycomb structures and the elevated‐temperature results indicate that bonded uninsulated aluminium sandwiches can be retained, even when the temperature due to kinetic heating approaches 70 deg. C. Finally, some remarks regarding future developments are made on various new ‘temperature‐resistant’ adhesives and on combinations of various materials for sandwich panels with external insulation, suitable for certain types of the next breed of supersonic aircraft.
The Library Shelf
Authors: W.A.M.  , J.H.  , S.L.B.  , D.B.S.  , J.E.D.
Published: November 2014

This is a reprint of a book that was first published in 1932. As there has been no revision of the contents since the original publication, no work done in the last twenty‐five years is included. Nevertheless, the book includes a con‐siderable amount of material that is still of interest.
The Estimation of Civil Aircraft Operating Costs
Authors: Thorne R.G.
Published: November 2014

EXISTING methods for the estimation of the direct operating costs of civil aircraft are complicated and their application in project or assessment work is often tedious and protracted. To enable rapid comparisons to be made a simplified formula has been derived. By linking this formula with the well‐known Breguet formula for the range of a jet propelled aircraft, cruising at constant speed and lift‐drag ratio, a graphical presentation of the influence of various design parameters on operating costs is possible. To enable the influence of all the basic design factors to be shown in chart form, it is convenient to divide the total direct costs into those related to fuel costs and those others such as maintenance, depreciation, crew costs, etc.
Creep Deflexion and Stress Distribution in a Beam
Authors: Goodey W.J.
Published: November 2014

THE work of Johnson, Mathur and Henderson on the ‘Creep Deflexion of Magnesium Alloy Struts’ raised the question in the present writer's mind of the stress distribution in the beam cross‐section, and the variation of this distribution with time. The precise computation of the stress distribution in an eccentrically loaded strut appears to be a very difficult problem, and the present note is concerned with the much simpler case of a beam subjected to a constant bending moment.
Semi‐Articulated Bogie Undercarriage Landing Performance
Authors: Person P.
Published: November 2014

IN recent years the bogie type of multi‐wheel undercarriage has been introduced on the medium and heavy range of aircraft. The trend began because of the necessity of keeping runway loadings to a minimum and the difficulty of stowing a large diameter single wheel in the wing or fuselage during flight. By spreading the main undercarriage ground reaction through two, four or more wheels, existing runways are able to accommodate heavier aircraft, while faster operational flight speeds have resulted in relatively thinner wing sections aggravating the stowage problem of the undercarriage. The interpretation of the bogie into practical undercarriages with their manifold performance duties has led to several types of mechanisms each with distinctive dynamical features. One such mechanism is the semi‐articulated bogie type and its general features have been previously described, The claims made for this undercarriage have been substantiated through several years of successful operational experience. Since this particular arrangement has obvious future applications both as a twin‐ or multi‐wheel version and, as it possesses characteristic dynamical features, it is considered appropriate to place on record the analysis of its landing performance.
Recovery of Guided Weapons
Authors: Jackson S.B.
Published: November 2014

OF the various countries involved in the development of guided missiles, the United Kingdom has a unique problem. It is that, apart from the preliminary use of the small artillery range at Lark Hill for scaled down missile trials, the major development has taken place over a sea range, at Aberporth. The test vehicles are almost invariably lost and much use has to be made of information transmitted in flight to ground equipment. A huge amount of technical effort has been expended to develop telemetery systems with great success. Even the ability to recover the test vehicle in one piece, a facility which can be readily obtained on a land range, is not a substitute for the collection of information in flight, for the operation of vital equipment has to be checked in actual working conditions and subsequent ground examination does not, necessarily, show if and why a failure has occurred.
Aluminium and Aircraft Engineering
Authors: Kennedy A.J. , Sollars A.R.
Published: November 2014

ALUMINIUM alloys have been important structural materials in aircraft from very early days, and there is no doubt that the course of aeronautical development would have been very different without them. It would be pointless to review the classification of these alloys and their respective fields of application in quite the same way as was done in the two previous articles of this series, those on titanium and magnesium. The aircraft industry has used many of the traditional alloys for years, and is highly familiar with their possibilities and limitations. In this article we shall outline, in the first place, the extent of present alloy development, giving some special attention to matters of particular aeronautical significance, and then limit further consideration to certain specific types of alloy which, for one reason or another, are the most promising as well as being the most difficult to use successfully in aircraft structures. These alloys are all of the high‐strength precipitation‐hardening type.
The Library Shelf
Authors: A.D.B.  , D.K.  , J.C.  , G.J.H.  , R.M.L.M.
Published: November 2014

Although the subject of this book has been much to the fore during recent years, the science and engineering associated with it have been little known by those not intimately in contact, and those who have would probably agree that until a few years ago it was on a far from firm foundation. Undoubtedly great strides have been taken since the spur of space flight has been applied and the present volume confirms this throughout its eight hundred odd pages.
Sandwich Construction
Authors: Heath W.G.
Published: November 2014

IN Part I of this paper, the basic equations were established for the various modes of instability of flat sandwich panels subjected to lengthwise compression. Whilst these equations are valuable in determining the strength of a given panel they do not give a direct indication of the cross‐sectional dimensions of a panel required to carry a given load, especially if the panel is to be the optimum, i.e. of minimum weight.
Effect of Structural Damping on Panel Flutter
Authors: Johns D.J. , Parks P.C.
Published: November 2014

The effect of structural damping on panel flutter has received little treatment in the literature but the available information suggests that such an effect may be destabilizing. By considering a two‐dimensional, simply‐supported panel and using linear piston theory for the aerodynamic forces an analysis is presented in which the effect of hysteretic structural damping is considered. The main emphasis is on flat unbuckled panels, although a brief investigation of buckled panels is also presented, and it is concluded that there is an interdependence of structural and aerodynamic damping, which in the range of Mach numbers for which piston theory is valid, shows the destabilizing effect of structural damping. This effect is apparently more pronounced at high altitudes. A comprehensive bibliography of panel flutter is also included.
Eleventh International Astronautical Congress
Authors: Thompson G.V.E.
Published: November 2014

Interstellar gas passing through the solar system may effect the interplanetary gas, planetary atmospheres and satellite orbits. Interaction of the interstellar and interplanetary gases is considered; a solar system corona may be formed.
Predicting Temperature Rises, Due to Aerodynamic Heating
Authors: Readshaw D.
Published: November 2014

In this paper it is described how trajectory data is used to calculate the distribution of temperature throughout the radome of a missile. The problem divides itself into two parts, one being the solution of the heat conduction equation within the medium of the radome, the second being the solution of the boundary condition at the surface. The method is easily applied to many other problems where a medium is heated by forced convection and in fact three independent problems have been solved using the method described here.
Calculation of Supersonic Aerodynamic Influence Matrices
Authors: Hallstaff T.H.
Published: November 2014

This paper describes a routine for calculating supersonic aerodynamic influence matrices, which is suitable for the digital computer. The method is first applied to a wing with straight leading edges, streamwise tips and a supersonic trailing edge. Then, an extension is given which enables wings of arbitrary planform (including those with subsonic trailing edges) to be treated without revision of the original programme.
The Library Shelf
Authors: R.N.L.  , J.C.  , A.D.Y.
Published: November 2014

This book is intended to be a comprehensive work of reference on the subject of radio aids to civil aviation. It is not written for the circuit designer or routine operator requiring detailed information on existing aids but rather for the system designer and operational planner. To this end it gives systems information required by the radio engineer or operational specialist. The inclusion at an early stage of some one hundred and fifteen pages devoted to the basic principles of radio propagation, radar, etc., assists those having a nodding acquaintance only with radio engineering to a better understanding of the later sections of the book; besides presenting a number of nomograms, graphs, and formulae directly useful to the systems designer.
Aircraft Refrigeration Systems
Authors: Leech D.J.
Published: November 2014

REFRIGERATION in aeroplanes does not, so far, involve the use of any techniques which have not already been established and used in other fields. These techniques must be considerably extended, however, and the features which distinguish this branch of refrigeration from others are that:
Recent British technical progress in aeronautics part Four—Machine Tool Developments
Authors: Cherry J.
Published: November 2014

WHILE Professor Melman's report on the machine tool industry in Western Europe brought many protestations at the time of its presentation, there is no doubt that since its appearance the British machine tool industry has indulged in self reappraisal, and—to its credit—it has reacted vigorously by the adoption of policies whose implementation is most likely to improve its position as a competitor for world markets of machine tools.
Estimation of Scale Effects in Axial Flow Fans
Authors: Barna P.S.
Published: November 2014

The losses in a fan unit consisting of rotor, guide vanes and tail fairing have been studied and the average losses are expressed in terms of non‐dimensional similarity parameters, frequently referred to as ‘fan laws’. It was found that for a specified duty and fan geometry the losses depend on: (a) The magnitude of the lift‐drag ratio of the rotor blades. (b) The drag coefficient of the guide vanes. (c) The loss over the tail faring. Since for complete similarity the parameters for model and prototype are considered to be equal, the discrepancy in losses between model and prototype, that is, scale effect, is mainly due to the variations of the aerodynamic characteristics of the blade and guide‐vane profile with the Reynolds number.
Design and Operation of Airborne Refrigeration Equipment
Authors: Gurney J.D.
Published: November 2014

This paper presents some of the problems associated with the design and operation of airborne vapour cycle refrigeration equipment, created by the extreme environmental conditions, and indicates where applicable the manner in which the difficulties can be overcome. The design philosophy behind a small high‐speed oil‐free reciprocating compressor is described, by certain fundamental requirements which the designer of airborne cooling equipment must consider. The particular difficulties, associated with effects due to rapid variation of ambient air temperature and pressure, which are peculiar to design and operation of such equipment are then explained. Rapid changes in heat load necessitate careful selection of the type of compressor drive and capacity control, and since extremes of temperature occur during a comparatively short operating cycle, particular attention must be paid to control of condensing pressure, and to prevention of migration of the refrigerant liquid into the low side of the system. The effects of vibration and of high acceleration make it necessary to design the components in such a manner that they can withstand these extreme effects, both while operating and during off‐cycle periods. In conclusion, the author contends that a new field of application for refrigeration equipment is emerging as a result of the more stringent aircraft and missile requirements; considerable theoretical and experimental effort is being devoted to the many problems, and the hope is expressed that continued co‐operation between the Refrigeration and Aircraft Industries may contribute to the more conventional as well as to the more specialized applications of refrigeration.
Aircraft Electrical Generating Systems
Authors: Simms T.E.
Published: November 2014

WE do not need to be reminded of the increasing importance of the electrical system in the modern aeroplane, either from the point of view of efficient operation of the aircraft or from the point of view of reliability and safety.
Moments of Area of Aerofoil Sections
Authors: Maltbaek J.C.
Published: November 2014

This paper considers the calculation of moments of area of aerofoil sections. Formulae have been developed for the calculation on an electronic digital computer of the area, centre of area and principal second moments of area of aerofoil sections with contours composed of circular arcs and straight lines. The method can be used for other cross‐sectional areas of a similar nature and can be extended to include areas with contours consisting of other types of curves.
Beware of Zero
Authors: Mayo C.G. , Head J.W.
Published: November 2014

For an engineer, ‘zero’ means a quantity less than the relevant tolerance; the size of this quantity is usually unimportant, but the sign may be critically important. The notion of ‘absolute zero’ lacks information about sign and belongs, with other conceptual ideas like ‘irresistible’ forces, to the world of metaphysics or theology, not mathematics or science. Statements about the real world should always be made in terms of inequalities, not equations, unless it is convenient to express the same entity in two different but equivalent forms, or the absence of critical comparison permits procedure as if exact equalities were possible. In mathematics, the relevant tolerances may be regarded as arbitrarily small, but they must not be forgotten. Adequate attention to tolerances and residual quantities in fact simplifies mathematics by removing ambiguities which are invariably associated with border‐line cases which occur with zero probability.
Boundary Layer Control for Low Drag
Authors: Lachmann G.V.
Published: November 2014

OPTIMIZATION of wing design aims at finding the best compromise between conflicting aerodynamic requirements and considerations of structure weight and stiffness. Since the profile drag of a laminarizcd aircraft is very small, the induced drag has to be correspondingly reduced for proper matching. Reduction of induced drag can only be obtained, for a given dynamic pressure at the cruise, by increasing the span, and that reflects on structure weight.
VICKERS VC10 Part One—Aerodynamic Design
Authors: A‐ Hay J.
Published: November 2014

THE VC10, as conceived in 1956, was an air‐craft developed specifically for B.O.A.C.'s Commonwealth air routes. For this, the requirement was to transport 32,000 lb. of pay‐load over stage lengths of up to 2,200 nautical miles at speeds in excess of M=08, coupled with the ability to operate from hot and high aerodromes with short runways. In this form, the plane evolved as a four‐engined jet aircraft, of about 240,000 lb. a.u.w. and 2,400 sq. ft. wing area.
Effect of Fuselage Dynamics on Helicopter Ground Resonance
Authors: Hooper W.E.
Published: November 2014

Of the parameters that may be adjusted to give the helicopter freedom from ground resonance, that which is ignored most frequently is Λ3 (ratio of effective rotor mass to effective fuselage mass). This is because it is usually impractical to change it on an existing helicopter. However, if it is considered sufficiently early in the design of the fuselage, the ground resonance problem can be greatly reduced or even eliminated by the consideration of this parameter alone. The paper investigates the effects of fuselage dynamic properties on Λ3 and also gives results for the effect of Λ3 on the stability boundaries for some simple helicopter configurations.
Recent British technical progress in aeronautics part One—Helicopter Developments A Review of the Technical Progress and Changes in Operating Techniques Which Have Taken Place Principally during the Last Six Years
Authors: Stewart W.
Published: November 2014

IN the September, 1956, issue of AIRCRAFT ENGINEERING, Mr McClements and Sq./Ldr. Armitagc surveyed ‘Helicopter Developments during the Post‐War Years’. The purpose of the present article is to discuss the subsequent developments which have taken place during the last six years. This period has been one of continued expansion in helicopter development and of much more widespread utilization of helicopters in both military and commercial operation. Since their initial development, over 150 different types of helicopter have been successfully flown. This figure includes many experimental machines or prototypes built by small groups. The major helicopter constructors have put about 40 types into quantity production and over 10,000 helicopters have been built in the Western countries. These have been predominantly for the military services, the large majority being built in U.S.A., but something approaching 2,000 have been used in commercial operations.
Overhaul Life Development, and Early Failure Detection of Aircraft Gas Turbines
Authors: Eden J.J.
Published: November 2014

Inspection of the engine oil pressure filter at regular intervals has been the mainstay of maintenance procedures with respect to declaring an engine unserviceable. The procedure generally consists of draining the cavity of the filter, removing the filter cover and withdrawing the filter. The filter is examined and on occasion washed over a cloth to examine more closely the particles. When this examination is completed, a decision is made in respect to the serviceability of the engine and the particles are thrown away. A survey of results achieved by only relying on a standard filter inspection shows that this method leaves a great deal to be desired.
Development of Synthetic Resin Adhesives
Authors: Catchpole E.J.
Published: November 2014

THE development of synthetic resin adhesives has proceeded very fast since about 1937 when the first urea formaldehyde wood glues were being produced on a pilot scale. The excellent resistance of these materials to weathering conditions has enabled very considerable advances in structural design both in wooden structures and rather more recently in metal aircraft. These synthetic resin adhesives are basically ‘thermosetting’, that is to say, they harden by the addition of catalysts or by the application of heat, the chemical process which takes place being irreversible and not dependent upon the evaporation of solvents. This concept leads not only to good weather resistance, but also to the practicality of sticking together non‐porous materials such as metal. The first use of bonding of mstal in aircraft structures was in the de Havilland Hornet in 1943,1 and since then bonding has proved its advantages over other methods of joining for both primary and secondary structures. Other new methods of fabrication have appeared since that time and the requirements for structures in terms of loading and environment have changed considerably; but both mctal‐to‐metal bonding and its newer partner honeycomb sandwich show signs of much more extensive use in the future. These two most important applications of synthetic resin adhesives in modern aircraft will now be considered.
Aerodynamic Design
Authors: Prior B.J.
Published: November 2014

THE overall design philosophy of the DAC One‐Elcvcn has already been described in the preceding papers on operating economics and systems—so that this article sets out to extend that information by explaining how the aerodynamic features of the aircraft enable the spscification of this short‐range twin jet to be met.
Rotor Dynamics and Helicopter Stability
Authors: Price H.L.
Published: November 2014

SUMMARY A detailed account is given of the aerodynamic and inertia forces acting on a rotor blade when the helicopter is undergoing arbitrary disturbance in velocity and angular velocity. A fairly generalized form is used for the downwash velocity. A principle is enunciated enabling the several second order terms of significance in the angle variables to be recognized and retained.
Spar Web Buckling of a Supersonic Aircraft
Authors: Webber J.P.H. , Houghton D.S.
Published: November 2014

SUMMARY An analysis is given for the buckling of a simply supported rectangular plate under the combined action of a number of in‐plane stresses. These stresses could arise in the various plate elements of the structure of a high‐speed aircraft, due to the combined action of aerodynamic and inertia forces with additional kinetic heating effects. The buckling solution of a wing spar web is considered, and the buckling criterion is presented in the form of a determinantal equation which may be evaluated to give the magnitude of the critical thermal stress under a given loading system.
The Radiographic Examination of Aircraft Structures
Authors: Norriss T.H.
Published: November 2014

THE examination of aircraft structures by radiographic means is a comparatively recent branch of industrial radiography. Spasmodic examinations of aircraft parts have been practised for a number of years, even as far back as the First World War, but it was not until six or seven years ago, that any form of planned radiography was undertaken.
Rotor Dynamics and Helicopter Stability
Authors: Price H.L.
Published: November 2014

High and Low Drag Helicopters. A parameter which has not hitherto received any attention is the value of the fuselage drag. For any particular helicopter the drag will depend on the extent to which it is carrying bulky external loads, and the top speed under the high drag condition will clearly be substantially reduced. It might therefore be thought that any investigation of the high drag helicopter at a value of? of, say, 0·3, would be unrealistic since, for one thing, the engine power requirements would be inordinately high, and for another, the rotor blades would be very severely stalled. However, such an investigation is not, in fact, valueless, and we shall find a posteriori, that although the high speed case is effectively an idealised one, it will nevertheless serve the purpose of throwing up in a much emphasised form certain (apparent) discrepancies, which, in the low drag case, would hardly have merited attention. In the high drag case, however, the discrepancies cannot be dismissed so lightly, and we shall be obliged to investigate their cause. In so doing we shall obtain a much greater understanding of the underlying physical phenomena.
The Development of Glass Transparencies for Modern Aircraft
Authors: Holland A.J.
Published: November 2014

The construction of windscreen panels for modern aircraft is described and the role of each component in meeting the requirements for pressure strength, bird resistance and optical performance is discussed. The influence of the physical properties of the windscreen components on the performance of complete laminated windscreens is discussed and the limitations imposed by these properties indicated. Silicone inter‐layers are beginning to replace polyvinyl butyral inter‐layers in high‐speed aircraft laminated transparencies when the temperatures reached are above the working limit of the conventional interlayers. New types of glass capable of withstanding prolonged exposure to higher temperatures than soda lime silica glass without loss of toughening stress, and also capable of withstanding more severe thermal shock without fracture, have been developed.
The Use of Nickel Base Alloys for Structural Applications in Hypersonic Flight
Authors: Hallwood S.W. , Wallis P.B.
Published: November 2014

An Assessment of the Temperature Environment likely to be Experienced by Hypersonic Aircraft, Type of Structure Suitable for Use in this Environment and a Detailed Review of the Properties of Nickel Base Alloys, Including their Manufacture and Fabrication, for Structural Use. THE demand for faster and yet faster air‐craft has continued unabated since the Wright Brothers made their first tentative flights some sixty years ago. In 1947 the sound barrier was broken for the first time by the Bell XI. and with the design and development of the Concorde and the American S.S.T. the first stages of breaking the heat barrier have been taken. The next generation of aircraft will be required to fly even faster, and it has been suggested that flight at hypersonic speeds, i.e. Mach 5 and above, will be the next step.
Rotor Dynamics and Helicopter Stability
Authors: Price H.L.
Published: November 2014

Development of a Unified Mathematical Theory of the Steady and Disturbed Motion of a Helicopter with Particular Emphasis on the Dynamical Aspects of the Problem. The basic features of the disturbed motion of a helicopter are first discussed, and the question of the separation of longitudinal and lateral modes is examined. This is followed by a detailed account of the entire family of helicopter stability derivatives. Particular attention is paid to derivatives involving cross‐coupling between the lateral and longitudinal modes because of the vital part they play in modifying the longitudinal stability behaviour. A full treatment is given of the flapping and downwash derivatives which play an integral part in the calculation of the main‐rotor derivatives. A method is then developed of calculating the tail‐rotor parameters to trim, and the values of the tail rotor derivatives are deduced. The contribution of the fuselage is also examined, and full expressions are finally presented for all thirty‐six derivatives of the complete helicopter.
Military V/S.T.O.L. Transport Aircraft
Authors: Brown D.G. , Jagger D.H.
Published: November 2014

SINCE man first aspired to fly the desire to take‐off and land vertically and to hover in flight has always presented a challenge to the engineer. To date only the rotary wing aircraft has achieved these aims in service but their shortcomings in terms of speed, range and economy have encouraged engineers to search for more elegant ways of achieving vertical flight.
Some Aspects of Military Aircraft Procurement
Authors: Beesly L.R.
Published: November 2014

THE subject of this Sempill Paper was suggested by The Institution of Production Engineers and I propose to deal with it in two sections. In the first, I shall give an outline of current procurement procedures; and in the second, attempt to identify mistakes of the past and offer personal views on some of the areas that need to be tackled more energetically if efficiency is to be improved.
A Low Weather Minima Flight Control System
Authors: Gardner A.A. , Roberts C.M.D.
Published: November 2014

IN recent years the regularity of scheduled services has become an increasingly important factor in the economics of the air transport industry. Service regularity is dependent to a marked extent upon aircraft reliability and upon the ability to operate in reduced weather limits. For this reason the requirements for low weather operations and for improved equipment reliability have become principal factors affecting the development of flight control equipment.
The Philosophy and Some Design Features of the Hawker Siddeley 748
Authors: Bradshaw P. , Nichols R.
Published: November 2014

For over thirty years the Douglas DC‐3 Dakota aircraft has operated in large numbers throughout the world on short to medium ranges, in many instances under primitive conditions. The need for a successor to this aircraft has taxed the ingenuity of the world's aircraft designers for a considerable time.
Aircraft Systems and Equipment
Authors: Page A.E.V.
Published: November 2014

THE special requirements of the market for the Jetstream led to a new approach in the matter of systems and ancillary equipment. The criterion in this field was to find the best mixture of British and American equipment that was available and whose reliability was proved and was backed by the manufacturers with a worldwide after‐sales service and product support. Care has been taken in the design stage to ensure case of access to the equipment to facilitate servicing. Another factor to be considered was the stretch potential of the aircraft, with the requirement of up‐grading the airworthiness to FAR Part 25 and BCAR Section D.
Sealants in Service
Authors: Lawson R.
Published: November 2014

THIS paper deals, in the widest sense, with the operational aspect of sealants in relationship to their uses in the construction of integral fuel tanks. It should be borne in mind, however, that on modern aircraft, particularly those with pressurised hulls, there are other applications equally as important.
Some Fatigue Problems Encountered in the Design of an Aircraft Landing Gear
Authors: Wood S.W.H.
Published: November 2014

UNTIL about ten years ago the basis for the design of aircraft landing gear was an arbitrary set of static strength requirements as specified in the British Civil Airworthiness Requirements or Av.P.970, which experience had shown provided an acceptable standard of safety. The number of landings achieved by most military aircraft, however, seldom exceeded one or two thousand and the fatigue performance was, therefore, generally acceptable.
Structural Development of the Concorde
Authors: Harpur N.F.
Published: November 2014

DEVELOPMENT of the supersonic transport is involving a wide variety of activities in all fields of aeronautics. This paper describes the work which has taken place, or is planned, in the field of structures. Although Concorde is designed for Much 2, a speed at which aluminium alloys can continue to be used as the primary structural materials, evaluation of the particular alloys chosen and study of their behaviour under complex temperature‐stress histories involves considerable laboratory effort. While many aircraft have already operated under these conditions none has previously had to last for at least 45,000 hours in service. This gives rise to the two most significant new design considerations, viz. creep and thermal fatigue. Creep affects the choice of basic material, the design of joints and the design of structures through its interaction with fatigue life. Thermal stresses, arising from differential expansions within the structure and superimposed upon the normal flight stresses, have a more important effect on fatigue design than on static strength. While the experimental techniques involved are novel, practical methods of accelerated thermal testing using convective heating and cooling are described.
Control Systems for Aircraft Electrical Ice Protection
Authors: Gauld J.E.A.
Published: November 2014

THE main purpose of this article is to deal with control system problems encountered with aircraft de‐icing applications.
The Use of Welding in Aircraft Design
Authors: Troughton A.J.
Published: November 2014

THE British aircraft industry will only survive if it is competitive in the world's markets. This applies in both the civil and military fields. Since the main function of an aeroplane is to provide the most economic means of transportation — or weapons system — any symposium on any manufacturing technique must regard the value of engineering aspect as paramount. Thus, R. & D. into welding is not just a pleasant academic exercise and it must be justified by its ability to provide more economic aircraft.
An Introduction to the Statistical Approach
Authors: Harvey R.A.
Published: November 2014

NOWADAYS one tends to associate the terra statistics entirely with numeration and mathematical analysis. It is perhaps of some interest therefore that when the term was first used in 1770 it was defined as ‘The science of the political arrangement of all the modern states of the known world’. Later (in 1787) it was related to the science of ‘the power of the several modern states arising from their natural advantages, industry, etc.’
Correlation Protected Instrument Landing System
Authors: Ford T.E.
Published: November 2014

THE guidance aid installed at most of the world's major airports is the Instrument Landing System which is currently being developed to cater for all phases of all weather landing programmes. For this application, the system has to achieve a guaranteed performance of less than one failure in ten million landings, thus inferring high equipment reliability and integrity. The VHF ground system at present installed consists of a localiser to provide azimuth guidance, a glide path transmitter to provide pitch guidance and marker beacons to give position information at distances of about 5 miles and one mile from touchdown. The guidance signals are formed by modulating two overlapping beams of different frequencies such that when the aircraft is on the extension of the runway centre line, equal modulations are received. This is termed zero difference in depth of modulation contour. The glide path signal is formed in a similar way with the zero contour defining a descent path angle of 3 degrees to the runway touchdown point. In the aircraft, the ILS receivers separate the demodulated tones by filters, and they are then rectified and compared differentially.
Partnership in Major Technological Projects
Authors: Edwards George
Published: November 2014

IN deciding my subject I had international collaboration in mind, and this was subsequently broadened to include the role of one's own Government as a partner.
Preliminary Design of Structural Components in Carbon Fibre Reinforced Plastics and Metals
Authors: Henney A.S.
Published: November 2014

A review of CFRP dealing with its processing, properties and some of the ways in which it could be used in conjunction with conventional materials. The importance of the utilization of carbon fibres in commercially useful as well as experimental structures is discussed. This may be achieved by using the fibres in conjunction with conventional sheet metal components, as a preliminary step toward the 100 per cent reinforced plastic structure. A few such applications are described, together with a brief summary of the fibre processing and properties as an aid to preliminary design studies.
Concorde Power Plant Fire Protection System
Authors: Davis R.A.
Published: November 2014

NOW that the first two prototype Aerospatiale/British Aircraft Corporation Concorde aircraft 001 and 002 have successfully completed their initial flight phase, the age of supersonic commercial transport airliners is almost upon us.
Skidding resistance of runway surfaces
Authors: WILLIAMS T.
Published: November 2014

THE factors which affect tyre/runway adhesion are complex and interdependent. This article will discuss some of these factors keeping in mind the relative influence varies with the particular conditions.
The theory of governing for aircraft turbo alternators
Authors: BURNS D.O.
Published: November 2014

CONSTANT frequency 400Hz 3 phase, aircraft main electrical power is mostly obtained by employing a main engine driven constant speed drive (C.S.D.) of cither the pneumo or hydromechanical type. The latter, in the form of the Sundstrand (USA) pattern, is the most used and over the years has been improved so that it is at present a very reliable unit. It is, however, very costly to buy and maintain and the quality of the governing it gives is not outstanding.
Rotocraft for alleviation of the aircraft noise nuisance
Authors: LEVERTON JOHN W.
Published: November 2014

SINCE in the context of this article it is the civil air transport application of rotorcraft which is of interest, only large passenger carrying rotorcraft are considered.
Swing wing
Authors: BIRD W.J.
Published: November 2014

THE OBJECTIVES of this article are twofold, firstly to argue the case for variable configuration aircraft, i.e. aircraft whose planform can be adjusted in flight to give optimum performance in differing roles; and secondly, to put forward proposals for a wing suspension designed to overcome the handicaps inherent in the method so far employed in mounting the wings of variable configuration aircraft.
V/Stol for the U.S. Marines
Authors: Miller Thomas H.
Published: November 2014

Because it is a small, mobile service that must make the most of every asset, the Marine Corps in the 1940s and early 1950s began to use the utility helicopter as a weapon system. Very quickly it became obvious that the “chopper” offered Corps commanders unprecedented flexibility in moving ground forces much faster than by surface transportation.
An Evolutionary Approach to the Design of Flight Decks for Future Civil Transport Aircraft
Authors: Bateman L.F.
Published: November 2014

This paper discusses a programme of work being carried out jointly by the British Aircraft Corporation and Hawker Siddeley Aviation, into the design of flight decks for future civil transport aircraft. The programme is aimed at exploring all aspects of flight deck design, in sufficient depth to enable decisions to be made as to whether or not significant changes could, or should be introduced into aircraft scheduled to enter service in the 1980s. Some of the information now presented has been published previously by my colleagues engaged on the programme. I make no apology for this, since any story worth telling is also worth repeating — and perhaps embellishing in the process.
Rolls‐Royce Adour
Authors: FORD T.
Published: November 2014

Available with and without thrust augmentation by afterburning, the Adour turbofan was first produced for the Anglo‐French Sepecat Jaguar. For this aircraft, the engine entered service in 1972 as the Mk 102 with a dry thrust of 5,115 lb which is increased to 7,305 lb when reheated. A non‐afterburning version of the Adour known as the Mk 151 is produced for the British Aerospace Hawk, and this began RAF service in 1976 with a thrust rating of 5,200 lb. The engine is also in service with the Japanese T‐2 trainer and F‐1 fighter as the Mk 801A, which has the same thrust ratings as the Mk 102.
Design for Economy
Authors: Marks P.A.
Published: November 2014

A Paper presented at the Conference of the International Federation of Airworthiness, the theme of which was ‘maintenance and economics’, and which took place in an atmosphere shadowed by the effects of world oil shortages and escalating oil prices on the costs — and indeed on the whole structure — of airline operations. If this is the most obvious influence upon costs it is certainly not the only factor involved. Raw material prices continue to rise, and certain alloying elements such as cobalt which are essential ingredients of today's high temperature metals are becoming increasingly difficult to obtain. Environmental pressures continue to exercise considerable influence upon the airlines and the aerospace industry, and whilst none would argue the importance of preserving our environment, the task of reducing noise and other forms of pollution from aircraft gas turbine engines cannot be fulfilled without considerable cost to both parties.
Controlling the Future with DSIC
Authors: Ford Terry
Published: November 2014

Through a combination of the resources of two large companies in 1977, Dowty Smiths Industries Controls (DSIC) has been in the forefront of the development and production of advanced engine systems and accessories. Prior to the formation of DSIC, early collaboration involving both hydromechanical and electronic technology had been undertaken which led to development programmes for the production of full authority digital engine controls. Similar research had also been carried out by Dowty in co‐operation with Ultra Electronics (now part of the former company). Ultra in fact, had produced the analogue system for control of Concorde's Olympus 593 turbojets.
Ground Movement Control and Guidance
Authors: ROLAND‐BILLECART
Published: November 2014

Cat. 3 operations have been pioneered in France by AIR INTER in conjunction with French Authorities.