bluuebunny/crossref_metadata_2025 huggingface dataset:
The Prevention of Fire in Aircraft
Authors: Glendinning W. G. , Drinkwater J. W.
Published: August 2016

A Fire Prevention Sub-Committee of the Aeronautical Research Council published its findings in 1922. At that time the major risk was from crash fires in which the fuel was ignited by the engine either directly or indirectly through the medium of oil, wood, fabric or dry grass. Preventive measures recommended included crash-proof tanks, with a suggestion that these should be carried on the wings; fire-proof bulkheads; fire-proofing of inflammable materials; cooling of exhaust pipes; and fire-proofing of magnetos. Fires in flight were usually in the carburettor and a successful carbon tetrachloride extinguisher was designed at the Royal Aircraft Establishment and tested in flight by the late Squadron Leader Norman. However, the weight of the system, about 35 lb. per engine, was considered excessive and the action recommended was to turn off the fuel and dive the aeroplane.
Cautionary Note Regarding Some Chemicals used for Transition Indication
Authors: Pankhurst R. C.
Published: August 2016

This note draws attention to the poisonous properties of certain chemicals which have previously been used for transition indication in wind tunnels, indicates which alternatives are safe, and suggests general precautions.
Aircraft Performance Estimation
Authors: Vernon C. O.
Published: August 2016

Almost the first thing anyone thinks of, when confronted with a type of aeroplane which he has not seen before, is its performance. He thinks, “ What will she do?” This paper is an attempt to set out the methods by which the performance is estimated for a new design.

The subject has considerable scope, and only a certain portion of it will be covered here: Level speed and climb, range (at constant r.p.m.) and the take-off run.

Before anything can be done at all, something must be known about lift and drag, and something about airscrews. These will therefore be considered first.
Lofting and Template Reproduction
Authors: Woodley S. P.
Published: August 2016

A meeting of the Royal Aeronautical Society was held at the Institution of Civil Engineers, Great George Street, Westminster, on 11th December 1946, at which a paper, “ Lofting and Template Reproduction,” by Mr. S. P. Woodley, was read by Mr. L. G. Burnard. In the Chair, Sir John Buchanan, F.R.Ae.S.
Airworthiness Of Civil Aeroplanes
Authors: Tye W.
Published: August 2016

In this lecture the aim is first to establish of position of “airworthiness” in the field of “safety”. To draw a comparison, airworthiness is but one element of a complex jigsaw puzzle in which all the pieces must properly interlock in order to produce a satisfactory safety picture. This parallel applies too in the sense that if the shape of one of the elements is altered, all the adjacent elements must be altered to maintain a perfect fit. Arising from this, it is clear that, if safety and efficiency of air transport are to increase, then airworthiness provisions must be ever more closely linked with the conditions under which the aeroplane operates. The second aim is to draw attention to those airworthiness matters to which the designer could most profitably direct his efforts.
Air Navigation
Authors: Macmillan Norman
Published: August 2016

The air flows past unseen as one flies. As it flows the invisible meridians and parallels pass with it, sharp but arbitrary demarcations imposed mathematically by man upon a sphere which he learned to measure long after he began to move intelligently about its surface; geographically non-existent hair lines which stubble the ends of certain radii projecting to the surface from the centre of our globe. But these same lines are cartographically displayed upon our maps, where we designate them graticules. And so the air navigator, resolving his position in the air above the surface of the earth as a mathematically unique point, knows both cartographically and geographically exactly where he is.
The Nature of The Torsional Stability of a Monocoque
Fuselage
Authors: Sezawa Katsutada
Published: August 2016

Although the problem of the stability of a fuselage that is subjected to
torsional force is important in connection with the case of light metal
construction of an aeroplane in flight, the theoretical side of the problem
does not seem to have received much attention. This is probably because of
the difficulty of obtaining its mathematical solution even in the case where
the fuselage is assumed to be a circular hollow cylinder.
Thus, I studied the problem in assuming that the fuselage is a cylindrical
shell for the first approximation. Southwell and Skan have dealt with the
stability of a plane elastic strip due to edge shearing forces, but their
result cannot be applied to the problem of the cylindrical shell unless its
length is very short. Schwerin seems to be the only one who has written on
the torsional stability of a cylindrical shell. Although his method of
constructing the differential equations of the equilibrium of a cylindrical
shell has been chiefly derived from Love's text book, and appears correct in
the main, yet owing to the certain apparent particularities on his part his
solutions of equations are open to grave doubts.
Duralumin Applied to Aircraft Construction
Authors: Lewis W. H.
Published: August 2016

The position to which aircraft construction has proceeded is due in a large measure to the intense metallurgical investigations of recent years. Amongst the materials that have arisen out of this are the light alloys of aluminium, and in particular, that known by the general name “duralumin.” This alloy plays the part of main structural material in many of our present-day aircraft. The object of this paper is to give a brief general account of duralumin with reference to aircraft construction.
The Trend of Development in Military Aircraft
Authors: Petter E. W.
Published: August 2016

The subject which I have chosen for my lecture this evening must be one of profound interest to all engaged in the design of aircraft to meet military requirements.

This country, with its great Empire sprawling over some three-quarters of the habitable globe and in many parts sparsely inhabited, must form an object of envy to nations cooped up within narrow confines with teeming and everincreasing populations. We therefore cannot shut our eyes to the possibility of attacks being made upon us which we shall have no alternative but to defend ourselves against, if we are going to exist and hold the Empire which our forefathers have bequeathed to us.

The next consideration which we do not require professional training in military or naval tactics to appreciate, is that the predominant and indeed possibly almost solitary duty will fall upon the aviation arm of our military forces to resist attack and carry on a war.
Calculation of the Motion of an Airship Under Certain Conditions
Authors: Williams D. H. , Collar A. R.
Published: August 2016

The work described below deals, in detail, with the methods whereby the motion of an airship can be calculated. The possible motions of an airship are affected by such factors as its stability, motion of controls, release of hydrogen, dropping of ballast, engine power available, and gustiness of the air. The methods to be described are capable of dealing with these effects either separately or combined in any arbitrary proportions.
Surging in Helical Valve Springs
Authors: Dick J.
Published: August 2016

The high-speed internal combustion engine presents many problems arising from dynamic effects. Amongst these is the phenomenon known as “ surging ” in the helical springs used for the operation of the valves.

If a helical spring is held at both ends, any disturbance in the spring passes up and down as a wave, being reflected at each end in turn. This to and fro movement continues until it is damped out by friction and air resistance. With most springs the speed of propagation of the disturbance is considerable and only a confused flutter of the coils is apparent to an observer. A disturbance of this type is caused by any movement of the end of the spring. The more abrupt the movement of the end, the more pronounced will the disturbance be. An instance of the type of movement producing a pronounced surge is that due to impact between the tappet and the valve when the valve commences to open.
“ Wapiti ” Steel Wings
Authors: Martin Brian
Published: August 2016

With the present-day normal type of wing the spars are the principal members, and I propose to start by tracing very briefly the evolution of the spars which are used in the Wapiti wings to-day.

The personnel of the Steel Wing Company have been designing and making spars ever since 1912. I shall start from the time when we first began to use what might be described as the box type of spar, which was composed of four strip steel sections.

The first spar that we made of the box type had channel webs with flat flanges, which had only shallow corrugations, and the rivetted joint was flat. This spar was not very efficient in steel, so we deepened the corrugations and curved the rivetted joint, and this gave a better result.
The Critical Diameter of the Carburettor Choke in Supercharged Engines
Authors: Fearn E. J.
Published: August 2016

In a recent article on supercharging, various practical conditions are given which place limits on the degree of supercharging possible with aero engines. Some time ago the writer was shown the results obtained with a supercharged engine and, although the performance was very creditable up to an altitude of 12,000 feet, above this altitude there was a remarkable decrease in power, this decrease being so considerable that it could not be readily accounted for. Various modifications were made in an attempt to improve the engine's performance at the higher altitudes, but without success, and it was only after a new type of carburettor had been fitted that improved results were obtained.
Testing Aeroplane Controls
Authors: Stevens H. L.
Published: August 2016

Before beginning this lecture I have first of all to thank the Air Ministry for permission to give it and to explain that any opinions expressed are my own and do not necessarily reflect the opinion of the Air Ministry.

Secondly I must express my appreciation of the honour conferred on me by the Society in asking me to deliver a lecture before them; though I wish they had chosen a less difficult subject.

As regards the title of this lecture it sounds very circumscribed, but you can't test anything without having a fair idea of what its complete function is or without some standard of reference; and in trying to discuss these parts of the problem I am afraid you will find that I have been, if anything, too. general.
The Origin and Development of Heavy—Oil Aero Engines
Authors: Pye D. R.
Published: August 2016

In this first lecture upon the origin and development of the heavy oil aero engine to be delivered under the Akroyd—Stuart foundation, it is appropriate to devote some space to the early history of oil engines generally, for it is certain that the aero engine of the future will claim a direct descent from some terrestrial parent. The early history moreover, of the heavy oil engine is of quite exceolional interest, both technical and personal.

Herbert Akroyd—Stuart was born in 1864.His father, Charles Stuart, owned a small engineering works at Fenny Stratford, and it was here that the son gained his training as an engineer. Between 1885 and 1890 he took out several patents for the improvement of oil engines, which appear to have been the outcome of his experience with a “ Spiel ” petroleum engine used for power generation at his father's works.
Certificates of Airworthiness
Authors: Howard H. B.
Published: August 2016

The object of the present paper is to place before the Society certain general considerations regarding the effect of airworthiness regulations on the design of civil aircraft.

I should like first to thank the Air Ministry Authorities for permitting me to read this paper, and to explain that any opinions expressed are entirely my own.

The Air Navigation Regulations, which set up organised Government control of civil aviation in this country, came into effect on the 1st May, 1919, so that the influence of Government supervision has been present during the whole period of post-war development of civil aviation.
Aerodynamic Theory
Authors: Glauert H.
Published: August 2016

To attempt to discuss aerodynamic theory in a single lecture is perhaps a rather rash undertaking, for the subject is so vast that a proper discussion would require a volume, or even a series of volumes. My object, however, is not to cover the whole field of aerodynamic theory with its manifold applications to aeronautical engineering, but rather to discuss some of the fundamental conceptions on which the theory rests, and to discover where theory can be helpful and where it is necessary to rely wholly on experimental results.
The Strength of Transverse Frames of Rigid Airships
Authors: Lyon Hilda M.
Published: August 2016

Recent developments in the design of rigid airships, as commercial air liners in England and Germany, and for military purposes in America, show a demand for greater lifting capacity, cruising range and speed. The increase in size is mainly responsible for radical changes in the structural arrangement of the transverse frames, introduced by the designers of the British airships, R.100 and R.101.
The Townend Ring
Authors: Townend H. C. H.
Published: August 2016

The work which forms the subject matter of this paper relates to a device for reducing the air resistance of an air-cooled radial engine. It can be added to the engine without completely enclosing the cylinders, either singly or collectively, in streamline casings of the conventional type, which usually render the engine inaccessible.
Aircraft Vibration
Authors: Constant H.
Published: August 2016

In the early stages of development of every form of transport, the pioneers have cheerfully undergone great extremes of discomfort and unpleasantness. As the sense of novelty and adventure began to lose its early appeal a slow but insistent demand for greater comfort arose. To-day, there is a growing tendency to take aeronautics as a matter of course, and an increasing demand for those standards of comfort which have become the rule in the older methods of transport.

The two factors that most seriously prejudice one's comfort in aerial transport are probably noise and vibration. The problem of aircraft noise was laid before you last session by Dr. Davies.

The engineer has seldom a good word to say for vibration. In all his schemes it comes to cross him like an ill-tempered fairy godmother. In the days when men designed by eye and worked in tenths of an inch instead of in thousandths, vibration was more of a nuisance than a serious problem. To-day, when factors of safety are being pared to the bone, when weight is regarded with a jealous eye and members are being stressed right up to the limits of their capacity—to-day, vibration is rapidly becoming a definite limiting factor in design, and the problem of vibration in all its varied forms, one of the most pressing that the engineer has to face.
The Design and Operation of Superchargers
Authors: Penn A. J.
Published: August 2016

Initially, supercharging of aero-engines was introduced with a view to restoring the pressure in the induction manifold at altitude to that corresponding to sea level. During recent years this has been changed, and supercharging is now employed not just to maintain sea level pressure in the induction manifold, but to boost engines at altitude, in order to develop high B.M.E.P.s and thereby obtain high power outputs at high power to weight ratios.
Towards Slower and Safer Flying, Improved Take-Off and Landing, and Cheaper Airports
Authors: Page Frederick Handley
Published: August 2016

To fly farther, to fly higher, and to fly faster, have been the aims ever urging the aircraft designer on to further progress. Of all, the lust for high speed is the most compelling. While the past few years have seen spectacular increases in the World's High Speed Record (see Fig. 1) still higher performance in the supersonic region will be commonplace in the near future. To attain these speeds, largely made possible by the increased power and light weight of the turbo-jet unit, the designer must seek out means still further to reduce aerodynamic drag.
The Anticlastic Curvature of Rectangular Beams and Plates
Authors: Ashwell D. G.
Published: August 2016

The pure bending of a rectangular beam about an axis parallel to a principal axis of its cross-section is well understood if its depth d is comparable in magnitude with its breadth b. The usual theory, noticing the geometrical fact that at any cross-section the longitudinal strains of filaments of the beam are proportional to the distances of the filaments from some neutral axis parallel to the axis of bending, postulates that the longitudinal stresses will vary in the same way.
Present Thoughts on the use of Powered Flying Controls in Aircraft
Authors: Lyons D. J.
Published: August 2016

It has long been the practice in engineering to use direct manual operation of the controlling parts of a machine, so long as it was within the strength of the operator, and so long as design of the operating gear was relatively simple. In innumerable applications, however, the increased demands for power by the controls, and the need for greater accuracy, have necessitated the development of servo mechanisms to drive them; that is, we have to sever, partially or completely, the direct mechanical link from operator to control, and use the inserted backlash, elasticity, and so forth, to meter power from an external power source.

In the flying control field we have come at this time to the transition stage, in that we have realised that, for a large number of applications, direct manual operation is impractical, and we are feeling our way towards suitable forms of servo controls for our various needs.
Some Unusual Aspects of Turbulence
Authors: Bethwaite F. D.
Published: August 2016

The first idea about unsteady motion in the atmosphere seems to have been the vague notion of “ Air Pockets”—areas or gaps, wherein the air just does not generate lift, and an aeroplane falls in consequence. It is astonishing how widely this view is still held.

Those engaged in aviation soon learned that unsteady flight was due to turbulence and two sorts, friction and orographical, were quickly recognised. Friction turbulence, which affects only the lower layers of the atmosphere, can best be observed by watching a soaring sea-bird in a breeze. The friction of the water surface creates a velocity gradient or variation of windspeed with altitude, and the bird will probably be diving down-wind, and climbing into wind, with no effort— from the bird's point of view a fair approach to perpetual motion. However, the air is really a mass of tiny eddies where friction is at work and close observation of the bird's wings and feathers will show them to be constantly in motion as they yield to each puff.
A Survey of the Technical Problems of the Design of Naval Aircraft
Authors: Farren W. S.
Published: August 2016

In a necessarily brief introduction it is best to choose a few topics which seem to me to be of first–class importance, and to leave it to the discussion to bring up others.

I wish it had been possible to include one other aspect of Naval aircraft in these introductory papers– the aircraft carrier. Many of the technical aspects of carriers may be more appropriate as a subject for the Institute of Naval Architects, but I feel that our discussion will be incomplete unless ship designers contribute.
A Possible Method of Impedance Testing Aircraft Power Control Units
Authors: Davies F. T.
Published: August 2016

Knowledge of the motions of aircraft control surfaces due to oscillating hinge moments is of great importance for flutter investigations. While the impedance of the power control unit may play a large part in determining these motions, it is not their only cause. The elasticity of the power unit mounting and the effect on the input of distortion of the aircraft structure, an effect which may depend on air speed, may also be important. Nevertheless the influence of the power unit itself is of major importance. No very satisfactory methods appear to have been devised yet, however, for making such tests. The difficulty lies chiefly in applying the large oscillatory loads to the output of the power control unit, which are necessary if the test is to be realistic. The facts that the oscillating loads must be applied to the jack while it is moving, and that a non-oscillatory opposing load is also desirable, add to the difficulties. For convenience in assessing the characteristics of the unit, it is desirable that the oscillating load should be superimposed on a constant opposing load and that the basic jack motion should be of constant velocity.
R 100
Authors: Brigham R. B.
Published: August 2016

The lecturer opened with a brief and general description of R. 100, which has an overall length of 709 ft. and a diameter of 133 ft., with a cubic capacity of 5,250,000 cu. ft. There are three power cars, each with two engines. These cars are situated at a considerable distance fore and aft from the passenger accommodation, and there was therefore a minimum of noise and vibration in the latter. The ship contained some 11 miles of special spiral seam tubing. Her displacement was 156 tons. In the Graf Zeppelin the cross sectional area of the girders equalled some 12 sq. ins., whereas in the British ship the cross sectional area amounted to 3 sq. ft.
An Experiment in Flying Training
Authors: Rattle A. C. W.
Published: August 2016

Late in 1947, at the instigation of the members of the Project Office of Short Brothers Ltd. of Rochester, an approach was made to the management of that Company on the subject of subsidised flying training for employees. Enthusiasm, unlike funds, was not lacking and the proposal was sympathetically received by the management, who agreed to make flight training to “A” licence standard available at one pound per hour, pre-1939 rates. The necessary apparel, including helmets and goggles, were supplied on loan, and training began at the Rochester Flying Club on Tiger Moth aircraft which were later supplemented by Magister and Auster types.
Flight Control
Authors: Draper C. S.
Published: August 2016

Flight before the Wright brothers demonstrated their powered man–carrying flying machine was based on the philosophy of vehicles with high inherent stability combined with pilots whose only duty was to steer. This combination resulted in low controllability and poor manoeuvrability, with a strong response to the disturbances of rough air. The Wright brothers broke with the high–inherent–stability concept and combined inherently unstable aircraft with three–axis control operation by human pilots to achieve stable flight systems with good controllability and good manoeuvrability. This change from inherently stable to inherently unstable aircraft was the basic contribution made by the Wright brothers to start the age of flight.

In this paper, a picture of the state of flight control before the Wright brothers is built up from references to the literature. A similar picture is drawn for flight control developments after the Wright brothers, and the effect of their efforts on the progress of events is discussed. Plots with time as the independent variable and non–dimensional ordinates are used to illustrate the overall pattern of past developments in flight control and to indicate the course of future progress.
Accident Investigation in Relation to Aircraft Design
Authors: Brown Vernon
Published: August 2016

The 777th Lecture was read before the Royal Aeronautical Society on 7th April 1949 at the Institution of Civil Engineers, Great George Street, London, S.W.1. Dr. H. Roxbee Cox, D.I.C., F.R.Ae.S., F.I.Ae.S., President of the Society, introduced the Lecturer, Air Commodore Vernon Brown, C.B., O.B.E., M.A., F.R.Ae.S., Chief Inspector of Accidents, Ministry of Civil Aviation.
High Lift Devices and their Uses
Authors: Duddy R. R.
Published: August 2016

The 778th Lecture to be read before the Royal Aeronautical Society (the second main Society Lecture to be given at a Branch centre) was read under the auspices of the Portsmouth Branch, at the Portsmouth Municipal College, on 21st April 1949, by R. R. Duddy, B.Sc., A.F.R.Ae.S., on “ High Lift Devices and their Uses.” Sir John Buchanan, President-Elect of the Society, presided over the meeting with Mr. E. C. Green, Chairman of the Portsmouth Branch.
Aerodynamic Balancing of Propellers
Authors: Milner H. L.
Published: August 2016

Despite the high standard of workmanship employed in its fabrication, a propeller, like any other manufactured article, invariably differs from the ideal product in some respect which may, or may not, be of functional significance according to the nature of the disparity. The component blades of a propeller are no exception to this rule and it is the author's object to examine the consequences of dimensional deviations of the actual blades from those of an assumed standard and to describe apparatus devised to minimise or eliminate the most undesirable of them, namely, the tendency to induce vibration in the aircraft. From the earliest day, aircraft vibration has been attributed to the engine propeller combination and has come to be regarded as an inevitable characteristic. It can be demonstrated, however, that where aerodynamically balanced blades are employed, vibration difficulties are not an inherent property of the propeller. This is a matter of considerable importance to the turbo-propeller in which the prime mover is virtually vibrationless and consequently any unbalance of the propeller would be thrown into prominence.
Development of Air Transport During the War
Authors: Cochrane Ralph
Published: August 2016

The heading of this lecture is the “Development of Air Transport During the War” but because time is limited I have had to exclude any mention of the ferry organisation which was responsible for the delivery by air of many thousands of aircraft. The work has however been, described in “The Atlantic Bridge.” The period with which I propose to deal is the 21 months ending in September, 1946. In this short period, in response to the demands of war, the Transport services of the Royal Air Force flew rather more passenger miles than did British Civil Aviation in the preceding 21 years up to the same date, and carried in addition great quantities of freight and military stores. This volume of transport flying, packed into a few short months, gave rise to many problems but also afforded unique opportunities for testing out new ideas and new equipment. My purpose tonight is to give a brief account of what was accomplished, and against this background to examine some of the lessons which were learned and the ideas for the future to which they gave rise.
The Application of Jet Propulsion to Military Aircraft
Authors: Carter W. G.
Published: August 2016

The association of gas turbines with aircraft designed to make effective use of the special characteristics of jet propulsion has brought the trend of development into a state of transition and uneasy experiment. Already speeds equivalent to a low level Mach number of 0.80 have been recorded under observed conditions.
Air Safety from the Pilot's Point of View
Authors: James J. W. G.
Published: August 2016

Before I present my written paper I would like to refer to two aspects of my subject which have been omitted from the paper, icing and static discharge.

I have no records of icing being a direct cause of accidents but it is important to appreciate the effect that it has on a pilot when flying an aircraft which picks up a lot of ice which he knows he cannot get rid of when he wishes. I look forward to the time when there will be installed on aircraft a de-icing system which will enable a pilot to get rid of ice at the right time.
Operational Research into Air Traffic Control
Authors: Bell G. E.
Published: August 2016

With the return of British civil aviation to normal operating conditions after the war it was found that several problems which had previously given little cause for concern had become acute. More especially, the increase in the volume of traffic, particularly under instrument flying conditions, together with certain indirect consequences of the greater sizes and weights of aircraft, had brought about greatly increased congestion around major airports, and there was, therefore, an urgent requirement for an effective system of close air traffic control to ensure the safety and rapid movement of the traffic.

The Ministry of Civil Aviation immediately gave much attention to this problem of air traffic control, but at once found itself in serious difficulties on account of lack of sufficiently precise knowledge of the traffic and the traffic pattern. The then Controller of Technical and. Operational Services, Sir Conrad Collier, realised that the obtaining of the necessary data concerning air traffic control and other matters of technical interest was essentially a matter of operational research, and in 1947 a small operational research section was established which began work in the autumn of that year.
A Critical Review of German Long-Range Rocket Development
Authors: Perring W. G. A.
Published: August 2016

Serious rocket development was started in Germany in the years 1929–1930 by a few groups of private inventors. This work attracted the attention of the Army Weapons Group in 1933, and in 1937–1938 a special research and development station was set up at Peenemunde at the cost of 300 million marks, and the work was transferred from Berlin to this new station at about that time.
Useful Load Ratio with Jet and Airscrew Propulsion of Aircraft
Authors: Lundberg K. O.
Published: August 2016

In a search for a rational basis for a transport-economical comparison of jet and airscrew propulsion of aircraft, a method has been developed which is generally applicable for evaluating any kind of propulsion of aircraft, as well as the efficiency of any principle or type of aeroplane design. The method is based on the assumption that the ratio between the useful load and the gross weight (or empty weight)—when related to the speed —is representative for the overall efficiency of the aircraft, including the power plant, from a transport point of view. General equations have been deduced for this useful load ratio as functions of, in addition to the speed and altitude, all major design parameters, as wing loading, power loading (or thrust loading for jet aeroplanes), specific engine weight, specific fuel consumption, parasite drag coefficient, effective aspect ratio, and two structural weight coefficients. This has been possible by the deduction of a formula for the gross weight, which appears to be usable even for general analysis of other aircraft performances, whenever the useful load has to be considered.

The method presented has been applied in this paper particularly for a comparison between jet-propelled aeroplanes and piston engine-airscrew aeroplanes. This has revealed that pure jet propulsion seems to be superior to the conventional system at speeds as low as 200 to 300 m.p.h., depending upon the duration in hours of flight and the detailed assumptions made.

Lack of accurate data for the gas turbineairscrew combination has prevented the writer from making a closer investigation of this system, but a preliminary study of the same kind seems to indicate that the turbineairscrew aeroplane—although for most purposes definitely superior to the piston engine aeroplane—is inferior to the pure jet aeroplane for durations up to about two hours of flight. If, however, all the mechanical complications involved in retaining the airscrew are taken into consideration, it appears doubtful whether the turbine-airscrew system will be any more than an intermediate step in aeronautical development. At the best, it might remain only for extremely long ranges, or transport of cargo at comparatively low speeds.

The conclusions drawn are based on the present stage of development of jet engines, but naturally it will take at least some three to six years before the jet aeroplanes contemplated are built and put into service.
Power Controls for Aircraft
Authors: Joy C. F.
Published: August 2016

In reviewing the various papers on power controls which have been read before the Society in the past few years, it soon became apparent that, considering the broad issues involved, there is little to add to what has already been said.

D. J. Lyons admitted, somewhat reluctantly, that power controls might become a necessity on aircraft designed to fly for extended periods in the transonic region.
The Theory of Limit Design Applied to Magnesium Alloy and Aluminium Alloy Structures
Authors: Panlilio Filadelfo
Published: August 2016

This paper is a study of the questions: (1) Are the simplified equations and design procedure in Limit Design that have been developed for application to structural steel construction, applicable without modification to light metal structures? (2) How do the properties of these metals which are different from those of steel affect the application of the theory? Do they offer any advantages? Any disadvantages? (3) What changes in traditional design procedure are warranted? What changes are imperative?

No claim is made to a complete solution of the design problem, since each particular structure involves a thousand and one details. Only the broad fundamental philosophy is discussed here. The discussion and conclusions are supplemented with a report of a number of experiments on a few extrusions of some of the more important alloys of magnesium and of aluminium.
Note on Ultimate Strength of Webs in Shear
Authors: Tatham R.
Published: August 2016

An investigation into the preparation of Data Sheets based on the work of Kuhn and Griffith at the N.A.C.A., revealed that it might be possible to present non-dimensional curves for the ultimate shear strength of aluminium alloy webs in incomplete diagonal tension, in a form similar to that of Structures Data Sheet 02.03.13, which are independent of material specifications. The values of “basic allowable shear stress” are founded on flat plate details from early experimental work and on estimated values for fully developed diagonal tension. Later work by Ross Levin provided further test results extending the range of diagonal tension developed, and the application of these to thick webs has been confirmed.
New Materials and Methods for Aircraft Construction
Authors: Pollard H. J.
Published: August 2016

About twenty years ago I was invited by the Council to read a paper before the Society, the title suggested being "The Use of Steel in Aircraft Structures." At that time steel, as the material for important parts of main structural members, was giving place to the then new and stronger aluminium alloys, and I decided that the lecture should be on something of growing, and not diminishing, importance; therefore in a paper entitled “ Some Developments in Aircraft Construction ” (March 1934) stiffened sheeted structure in aluminium alloy was chosen as the theme of the subject. The paper was as up-to-date as possible, but it contained no pictures or descriptions of British aeroplane structure of that type because in this country no aeroplanes (except the odd one in which fabric had simply been replaced by aluminium alloy) designed basically in that way had been built.
Strain Energy Proof of the Elastic Centre Method for the Analysis of Frames
Authors: Samson Derek R.
Published: August 2016

Frame analysis problems in general involve the determination of the values of three redundancies, which can become somewhat laborious. By applying the redundancies at the elastic centre of the frame the amount of work is much reduced and the solving of simultaneous equations is avoided. The method does not seem to be very widely used and it is considered that this may be due partly to the way in which the proof has usually been presented. The following proof is given in the hope that it may assist in clarifying the method.
Some Aspects of Noise From Supersonic Aircraft
Authors: Lilley G. M. , Westley R. , Yates A. H. , Busing J. R.
Published: August 2016

The noise problem associated with an aircraft flying at supersonic speeds is shown to depend primarily on the shock wave pattern formed by the aircraft. The noise intensity received by a ground observer from a supersonic aircraft flying at high as well as low altitudes, is shown to be high, although it is of a transient nature.

A study of the shock wave patterns around an aircraft in accelerated and retarded flight is shown to lead to an explanation of the one or more booms, of short duration, heard by ground observers after an aircraft has dived at supersonic speeds.

The shock wave patterns associated with an aircraft flying in accelerated or retarded flight at transonic speeds are shown in certain cases to be very different from the corresponding patterns observed in steady flight. The significance of these results, with reference to problems of flight at supersonic speeds is briefly discussed.
Fatigue in Aircraft Design
Authors: Stephenson B. E.
Published: August 2016

The problem of fatigue in aircraft design is a comparatively new one so far as the airframe designer is concerned. There are three main reasons for its prominence. Firstly, the utilisation rate has increased enormously, particularly with transport types; indeed, the hours flown by a civil aeroplane in a single year nowadays far exceed those in the whole life of a bomber up to the period of the 1939-45 War. Secondly, the increased cruising speeds of modern aircraft have aggravated the loading conditions which give rise to fatigue; and thirdly, the development of modern high strength light alloys has enabled higher ultimate stresses to be used, although the fatigue resistance of the material has not kept pace with its ultimate strength.
Lifing of Aircraft Equipment
Authors: Stevens H. L.
Published: August 2016

Reading the paper by Tye and Cundall in the June issue of the journal, I was started on a train of thought on the same lines.

I agree with the paper but feel that the argument has not been taken far enough. The main conclusion is:–

So long as a random failure is no more expensive and troublesome than a controlled replacement, it is always cheaper to wait until an item fails before replacing it. This is quite independent of the law of failure with time.
Some Problems in the Development of Air Transport in West Africa
Authors: Walker Hubert
Published: August 2016

West Africa, particularly British West Africa, has been one of the last areas to be opened up to Air Transport and because of physical and financial difficulties, progress has been slower than in most other parts of the Empire.

As West Africa, even today, is not very well known in other parts of the Empire, it will be useful to give a brief description of the territory and the early history of aviation there before dealing with the special problems encountered in the development of air transport. While the particular territories dealt with in this lecture are the four British West African Colonies and Protectorates of the Gambia, Sierra Leone, the Gold Coast and Nigeria, it will be necessary, from time to time, to make passing reference to the adjacent French territories and even to the Anglo–Egyptian Sudan. The four British territories, unlike those in East Africa, are not contiguous but each is surrounded on the land side by the intervening French territories of Senegal, Guinea, Ivory Coast, Dahomey, Volta, Niger, Chad and the Cameroons.
Modern Wind Tunnel Balance
Authors: Leavy L. E. , Saunders C. G.
Published: August 2016

Because of the limited nature of its application the wind tunnel balance has never been the subject of steady development along well defined lines such as are discernible in the development of most other mechanisms of comparable size and complexity.

The diversity of types and forms of balance which have been constructed in the past, reflect the wide range of tunnel sizes, financial resources, and personal preferences which are characteristic of some laboratory equipment.

The design and construction of a balance suitable for use in a medium–to–large industrial wind tunnel is a relatively costly undertaking, and the problem of providing such equipment is made more difficult by the paucity of published information, of a sufficiently detailed nature to be of assistance in making a decision on either a suitable specification for this class of machine, or the practical means by which a specification can best be met.

As part of the modernisation of the Blackburn and General Aircraft Aerodynamics Laboratory at Brough, a new six–component balance was installed, some few years ago, in a 7 ft. x 5 ft. wind tunnel having a maximum speed of 300 ft./sec. A detailed description of this balance is given.
A Method of Calculating Stresses in a Non-Uniformly Thick Disc Subjected to Asymmetric Loads, Adapted to a Tabular Computation
Authors: Hodson B. A.
Published: August 2016

Symmetrically loaded circular plates of constant thickness are dealt with adequately in several of the standard textbooks on the strength of materials. The problem of non-uniformly thick plates subjected to symmetric loading has been discussed by M. Donath and, more recently, by D. C. Boston. So far very little has been done on the problem of a circular plate of varying thickness subjected to an asymmetric load. A tabular method approximating to the solution is outlined in this note. A typical example of the problem arises in certain manoeuvres of a jet aircraft in flight, the rotor discs of the engine being then subject to gyroscopic moments.
Modern Methods of Aircraft Production
Authors: Badré Paul
Published: August 2016

The subject of aircraft production is obviously a very wide one—books have already been written on it—books which have been consulted when preparing this lecture. It is proposed to sketch in broad outline the various methods generally known for the manufacture of aircraft, dwelling perhaps more particularly on some with which I am more familiar and which have recently been used very successfully in French factories. Familiar processes which have been in use from the earliest stages of aviation development up to recent years will not be discussed, but an attempt will be made to bring out the salient particular features of the new processes and the new production methods which seem to offer interest not only from the historical, but also from the technical, aspect at the same time indicating the extent to which aircraft engineers have had to exercise their ingenuity in order to build and mass produce aircraft which are being constantly developed and improved by the Design Offices in different countries.
Two-Dimensional Bow Shock Wave Detachment Distances
Authors: Bryant R. A. A.
Published: August 2016

In the recent paper by Warren a summary was made of current data on two-dimensional bow shock wave detachment distances. It was shown that the experimental results of Griffith and Alperin, as well as the detachment distances computed by Vincenti and Wagoner, could be collapsed into a single curve by using Spreiter's Transonic Similarity Parameter. This has been confirmed by the present authors who have found that the experimental results for wedges obtained by Bryson also correlate favourably with the curve given by Warren (Fig. 3 of Ref. 4).

The results of the foregoing workers have been for steady flow conditions. However, it has been noted by Lilleyet aliathat a steady shock wave pattern can be established in free flight only after steady motion has been maintained for a considerable (infinite) time. In general, the locus of detached bow shock waves depends on the time history of the motion whenever a body is accelerated from subsonic speed.
The Fatigue Properties of Z-Section Test Pieces Completely Machined from an Aluminium Alloy Extrusion Conforming to D.T.D. 364B
Authors: Forrest G. , Gunn K. W. , Woodward A. R.
Published: August 2016

In 1949 F. H. Pollicutt, in the course of a discussion on a paper presented by P. B. Walker to the Royal Aeronautical Society, reported fatigue test results which indicated that when the aluminium alloy conforming to specification D.T.D.364 was tested, under , axial loads, in the form of Z-sections, its fatigue properties were extremely low. Z-sections with unmachined surfaces and even Z-sections with completely machined surfaces failed after short endurances at stress ranges under which small polished round test pieces would not have failed even after hundreds of millions of cycles. Pollicutt, in discussing these low values, advised that great caution should be exercised in their interpretation, warning equally against an unqualified acceptance of the testing technique and a too facile acceptance of small polished round bar test results.
Aeronautical Research in Sweden
Authors: Lundberg Bo K. O.
Published: August 2016

I wish first to express my deep appreciation for having been invited by the Council of the Royal Aeronautical Society to present a lecture on aeronautical research in Sweden. As the subject is a very broad one, it was necessary for me to consider rather thoroughly what would be expected from this paper and thus, which limitations in its scope should preferably be made.

Before the 1939-45 War it was possible to design new, successful aeroplanes mainly on the basis of experience from previous types in combination with generally available design information, such as aerofoil data. The success was, in fact, often more dependent on the skill of the designer than on the amount of research and detailed aerodynamic and structural testing done. After the advent of jet propulsion and transonic and supersonic speeds this situation changed radically. Nowadays a substantial amount of basic and applied research, as well as scientifically performed development work, is a necessity for any country, regardless of size, attempting to produce its own designs of efficient and safe aircraft.
A New Method for the Solution of a Differential Equation with Two-Point Boundary Conditions Applied to the Compressible Boundary Layer on a Yawed Infinite Wing
Authors: Crabtree L. F. , Woollett E.R.
Published: August 2016

The compressible laminar boundary layer on a yawed infinite wing is considered in Ref. 1, where it is shown that the problem may be solved by a direct solution of the linearised equations of motion under certain assumptions. As an example of this procedure the boundary layer near a stagnation point was calculated. Tinkler has published solutions of the exact equations for the general Falkner-Skan case (Ref. 1) obtained on the M.I.T. differential analyser for several values of the parameter involved. It has been found that the numerical results of Ref. 1 were in error and the corrected results obtained by a new method are tabulated below. Tinkler's exact solution of the stagnation point flow for ω = 0·10 is also given for comparison, and it will be seen that there is close agreement
Some Evaporation Measurements on Liquid Sprays
Authors: Bergwerk W.
Published: August 2016

The evaporation rate of a liquid spray in a turbulent gas stream is of interest in connection with direct contact heat transfer and combustion equipment. Any fundamental approach to this problem has usually dealt with single drops evaporating in an “infinite” atmosphere. The evaporation of sprays from actual atomisers is obviously a more complicated process and few attempts have been made to find in how far single drop data may be applied, or to measure the evaporation from a whole spray.

The main difficulties lie in devising a satisfactory method of measuring the evaporation rate. Selden and Spencer, injected the liquid into a bomb filled with hot gas under pressure and measured the decrease in pressure with time on a special indicator.
Stresses and Deflection in a Flat Plate with Clamped Edges under Normal Pressure
Authors: Oaks J. K.
Published: August 2016

Tests were made at the request of the Royal Aeronautical Society Structures Committee to extend the information on Data Sheet 02.09.02 from a value of the parameter.