bluuebunny/crossref_metadata_2025 huggingface dataset:
A three-dimensional field-integral method for the calculation of transonic flow on complex configurations — theory and preliminary results
Authors: Sinclair P. M.
Published: July 2016

A three-dimensional integral formulation for the solution of the full potential equation and the associated numerical algorithm, the field-integral method, are presented. The method is a direct extension of a two-dimensional method and in particular retains the simple grid generation requirements noted in that method. Results are presented for the flow over body shapes and a complex winglet configuration, and are compared with existing transonic methods and experiments with good agreement. The further work necessary to provide a fast, robust method for use in design is outlined.
Developments in computational methods for high-lift aerodynamics
Authors: King D. A. , Williams B. R.
Published: July 2016

Viscous/inviscid interaction techniques for calculating the flow about multiple-element aerofoils have been under development in the UK for the last decade producing such programs as MAVIS and HILDA. These methods give reasonable predictions of the lift for viscous attached flow, but fail to give an estimate of the maximum lift and the associated flow separations on the aerofoils. The methods also fail to give adequate predictions of the drag for both attached and separated flow. The disappointing performance of the methods in predicting maximum lift stems primarily from the use of direct methods to solve the first order boundary-layer equations, whilst the poor drag predictions arise from inadequate methods for predicting the development of the flow over the flap. The assumption of incompressible flow could also be a contributory factor in both cases. Methods of overcoming the first restriction are described by using a more appropriate coupling between the inviscid and viscous flows which properly assigns the correct role to each partner in the coupling: this approach is illustrated by ‘semi-inverse’ and ‘quasi-simultaneous’ couplings of a finite-element method for the compressible inviscid flow with an integral method for the boundary layers and wakes. Some methods for calculating the compressible flow about multiple-element aerofoils are also reviewed. However these improvements do not give an adequate estimate of the drag so possible improvements to the calculation of the flow over the flap are discussed.
An introduction to the dynamics of air propelled vehicles for sand deserts
Authors: Abulnaga B. E.
Published: July 2016

The concept of air propelled vehicles to travel in deserts is reviewed. An analysis of trafficability problems in Egyptian deserts is presented with emphasis on sand surfaces. Theoretical equations are derived for the prediction of acceleration, resistance to motion and range at constant speed of the Aero-Roue and the hovercraft over sand.
Geometrically nonlinear finite element analysis of sandwich panels
Authors: Al-Qarra H. H.
Published: July 2016

A displacement-based versatile and effective finite element analysis of sandwich panels is presented. The analysis is applicable to both small and large deflections. Allowance for the local bending stiffness of the faces is made. The procedure described is readily adapted to arbitrary laminated beams and plates. Selected example problems are given to illustrate the applicability of the formulation.
Generation of axi-symmetric body shapes in subsonic flow by means of polynomial distributions of sources and doublets along the axis of symmetry
Authors: Christopher P. A. T. , Shaw C. T.
Published: July 2016

A method is presented for determining the potential flow around bodies of revolution, at incidence, in uniform, incompressible, flow. This method utilises polynomial distributions of both sources and doublets, in the manner of Fuhrmann, and gives considerable advantage over existing techniques. In particular, when compared with the method of Nielsen, in a typical case, the computer storage requirement is reduced by a factor of eleven. Compared with panel methods the saving is very much greater.

Unlike the method of Landweber, both body surface and flow field conditions are obtainable and it would appear that the new method is ideally suited to the ‘store trajectory’ application in place of the existing discrete source method.
27th Lanchester Memorial Lecture scale effect in transonic flow
Authors: Haines A. B.
Published: July 2016

I must start by thanking the Royal Aeronautical Society for the invitation to present this 27th Lanchester Memorial Lecture. It is an honour and a privilege to follow in the footsteps of the distinguished scientists and engineers who have given the first 26 lectures in this series. These lectures have included many outstanding reviews of a wide range of different topics and I am very conscious that they have set a standard that I, for my part, will find difficult to match. I hope, however, that by choosing a topic that has only been mentioned in passing in just a few of the previous lectures, I will be able to make my own distinct, individual contribution to this tribute to the memory of a man who was not only a great scientist and engineer and talented musician but who, by his writings as long ago as 1907, still carries a message for us today in 1987.
Correlation of predicted and free-flight responses near departure conditions of a high incidence research model
Authors: Jean Ross A. , Edwards Geraldine F.
Published: July 2016

The mathematical model of aerodynamic forces and moments is described, based on results from various wind-tunnel experiments with the RAE High Incidence Research Model (HIRM). Simulations of the responses due to longitudinal and lateral control inputs at high angles of attack are compared with the responses measured on free-flight models of the configuration. It is shown that the main features of the flight behaviour are reproduced, in particular such phenomena as roll-off, wing rock and nose slice.
9th Sir Sydney Camm Memorial Lecture Jubilees in Design and Development — some comments on change over the period of Camm's work and influence
Authors: Fozard J. W.
Published: July 2016

The paper traces the evolution of Sir Sydney Camm's Kingston Design Office through an examination of internal practices and external technical and other pressures at three Jubilee points in its history from 1935 to 1985. Some personal observations are given on the achievements of Camm and his team and an account offered of their continued success over a period of half a century.
Prediction of vortex lift of non-planar wings by the leading-edge suction analogy
Authors: Hardy B. C. , Fiddes S. P.
Published: July 2016

A three-dimensional panel method has been used to calculate edge-suction forces for thin sharp-edged wings in incompressible flow. The suction forces have been used to estimate the vortex lift on the wings by means of the leading-edge suction analogy due to Polhamus.

The results for planar wings are in acceptable agreement with other methods based on the suction analogy. A limited comparison with results from experiments for non-planar wings revealed good prediction of lift and drag increments associated with the deflection of leading and trailing edge flaps for ‘conventional’ wings of high sweep, but only moderate agreement for a grossly non-planar configuration.
Generic vibration of prestressed thick orthotropic cylindrical shells
Authors: Yang I.-H. , Kuo W.-S.
Published: July 2016

An investigation of the generic vibration of prestressed thick orthotropic cylindrical shells was carried out. A set of Flügge type equations. of motion for orthotropic shells has been reduced to an equivalent set of equations containing only non-dimensionalised geometrical parameters, loadings and generalised global constants of orthotropic materials. The influence and importance of the global constants on the vibration of cylindrical shells are studied. Based on the results, the figures shown in this paper are applicable for a large group of materials, making the understanding of the correlation between composite material properties and vibrational behaviour of the shells very easy. The results of this paper show that an increase in vibrating frequency is brought about by (1) increasing generalised rigidity ratio, (2) increasing transverse shear modular ratios, (3) decreasing generalised Poisson's ratio and (4) decreasing principal rigidity ratio. The key parameters to the problems are generalised rigidity ratio and principal rigidity ratio only.
Experimental studies of viscous regions near streamlined wing tips
Authors: Horton H. P. , Xenophontos X. M.
Published: July 2016

Wing-tip vortices are of considerable practical importance, primarily because of the associated induced drag. A number of investigations have been made in the past into the development of vortices trailing behind wings, but little attention has been given to the mechanism of generation of such vortices. In the region of a wing-tip the boundary layers, which are usually turbulent at full-scale, separate from the wing surface in a rather complex manner to form a vortex sheet which rolls up into the tip vortex. Although the gross effects of the tip vortex can be predicted by inviscid theory, a detailed understanding of the behaviour of the viscous layers around wing-tips could lead to better optimisation of their design.
Part 4 — Two dimensional dynamic stall
Authors: Hancock G. J. , Lam J. S. Y.
Published: July 2016

An axiomatic aerodynamic model has been developed for the general motion of a two dimensional aerofoil as it passes in and out of stall, which gives realistic unsteady loads as compared to experimental values. A non-linear set of aerodynamic derivatives with time delays have been derived from the axiomatic aerodynamics. ‘Actual’ and ‘predicted’ dynamic responses of an aerofoil, spring restrained in torsion, following an impulsive input show similar trends, including limit cycle oscillations, although there is a slight difference in frequency and a difference in the magnitude of the initial impulse required to trigger the limit cycle.
Some Technical and Management Considerations in European Space Programmes
Authors: Pardoe G. K. C.
Published: July 2016

In 1957 the successful launching of the first artificial earth satellite had little immediate effect on the technical activities of the Aerospace Industry of the European countries. It was some years before various countries in Europe either singly or collectively allocated significant funds from their national budgets to allow any real research and development work to begin. In Britain, for example, it was only with the cancellation of Blue Streak in 1960 that the question of determining some sort of national policy in space activity was really brought into focus.
Part 1. Practical Problems
Authors: Gordon-Burge H. K.
Published: July 2016

At the outset, I must make it quite clear that any views or opinions expressed are my own and are not necessarily those of either British European Airways or the Flight Safety Committee.

In this paper, I have attempted to discuss some of the problems which face those whose task is to obtain and to disseminate safety information. At the end, I have posed a number of questions which I believe are relevant and should be posed, and which Harold Caplan will take up in his subsequent discussion of the legal problems.

Air Safety is essentially the prevention of accidents by minimising the risk of encountering foreseeable hazards and the consequences of unforeseen situations. Thus the dissemination of air safety information is simply the spreading of accident prevention material. It is undoubtedly best achieved by a sharing among all concerned of the lessons learned from their incident and accident experience. This activity is one that has to be shared by operators, flight and ground crew, air traffic control, the designers and makers of aircraft, engines and equipment, and regulatory authorities.
On the Approximated Expression of the Axial Perturbation Velocities in the Actuator Disc Theory
Authors: Bussi G.
Published: July 2016

Fluid motion in an annulus is described, in the absence of radial velocity, by the simple radial equilibrium equation. This equation is used to describe the flow in an axial turbomachine some distance ahead and behind the rows of blades, where radial displacements have already decayed.

In the neighbourhood of and between the blades the fluid motion is far more complex than the flow in the radial equilibrium condition. Most of the difficulties of the real problem can be overcome by introducing the actuator disc mathematical model. The actuator disc divides the complex flow field into two simpler fields, each free from blades, i.e. a simple annulus. The equations of motion in each field are easily linearised by posing some particular restrictions concerning the velocity profiles and by conceiving the velocity as the sum of the radial equilibrium solution and of small perturbed quantities. These are radial and axial perturbation velocities vanishing far from the actuator disc, and are given by a perturbation velocity potential.
Static Hovercraft over Water
Authors: Alexander A. J.
Published: July 2016

The problem of a static two-dimensional hovercraft over a solid surface has been studied by many authors and the solutions show reasonable agreement with experiment; the main source of error appears to be the neglect of viscous effects in the simple theories. It was recently pointed out by Hogben that no comparable simple inviscid solution exists for hovercraft over water. The main difficulty with the over-water solution is that there is no obvious reason why water should not occupy part of the cushion and some extra condition would be needed to determine this depth of water h2.
On Assumed Displacements for the Rectangular Plate Bending Element
Authors: Dawe D. J.
Published: July 2016

Summary:—

A family of alternative expressions is presented suitable for the representation of the lateral deflection of rectangular plate elements in bending. Such expressions are extensions of a simple polynomial representation assumed in earlier work. The new expressions are such that not all displacement continuity conditions are met completely but, nonetheless, a criterion ensuring convergence of numerical results to true stiffness levels is satisfied. Deflection and natural frequency estimates based on one expression of the proposed family demonstrate rapid convergence and high numerical accuracy.
The Displacement of the Nose Shock Wave from a Pitot Tube under a Streamwise Velocity Gradient
Authors: Sloan D.
Published: July 2016

Summary:—

The pressure reading of a pitot tube in a supersonic flow corresponds to the position of the nose shock wave. Results of measurements of the shock stand-off distance are presented for three different streamwise Mach number gradients and for a uniform flow. These results are compared with existing theoretical values.
Experience with a V/STOL Tunnel
Authors: Kirk J. A.
Published: July 2016

Although the Hatfield tunnel has been doing some useful testing for just over eighteen months, the experience so far obtained is still limited as each new model brings its own special problems. It is perhaps still too early to give an account of the experience obtained, but because of the interest in this tunnel it was thought that an account, even incomplete, would be useful.

Almost every facet of experience so far obtained is related to some of the special design features of the tunnel and I propose to review some of the problems encountered during the design stages of the tunnel dealing with these design features, before reviewing the actual model testing experience.
Comparative Cost Analysis
Authors: Connolly J. V.
Published: July 2016

The formation of the Steering Committee of the Management Studies Group is not an isolated manifestation of concern on the subject of management in the aircraft industry. During the past five years there have been events such as the loss of technologists to other countries, the massive cancellations of advanced projects, the Plowden Committee and many debates and ex parte statements by both the various Ministers and by industry spokesmen.

In addition to the public debate, there have been less formal meetings and approaches to the Council or the President of the Royal Aeronautical Society which indicate deep concern—almost universal—about “cost effectiveness” or, bluntly, our cost comparisons with competing aircraft industries elsewhere.
Digital Study of a Stability Analogy
Authors: Thornton B. S. , Park T. M.
Published: July 2016

An investigation has been made into the stability of compressor blade flutter in separating flow in the presence of external perturbations. The fluttering blade is an example of a hysteretic system governed by a non-linear difference-differential equation for which an analytical approach is not possible and for which the authors originally proposed this new treatment. For design purposes a digital computer has been used to produce stability diagrams under specified conditions including blade torsion. The solution for the response is also available if required. The method involves forming the non-linear feedback analogue to the blade system and which has behaviour governed by the same equation as that studied. The stability is then studied on a digital computer in the presence of small external perturbations by means of a dual input describing function applied to the analogous feedback system with consideration given to the aerodynamic phase lag involved and initially small blade torsional motion.
Boundary Layer Influence on the Performance of Submerged Intakes
Authors: McCreath Katherine M. , Ward Smith A. J.
Published: July 2016

Submerged intakes are widely used on aircraft as a means of supplying internal flow systems with ambient air. It is the purpose of this note to show by analysis of existing experimental data that the boundary layer at the location of the submerged intake can have an appreciable effect on its performance.

Information here relates to the NACA type of divergent submerged intake with a ramp angle, a, of 7° and an aspect ratio, w/d, of 4 because this particular combination of planform and geometry is now almost universally used.
Convective Heating at the Deflecting Surface of a Rocket Launch-Pad
Authors: Jepps G. , Robinson M. L.
Published: July 2016

When a large rocket or missile is fired, the hot exhaust gases must be allowed to escape without damaging structures or equipment in the vicinity of the firing area. Generally, the exhaust gases are directed harmlessly away from the launching installation by water-cooled deflecting surfaces fabricated in steel. In arid areas such as Woomera, where water is not available in large quantities, there is the possible danger that a steel efflux deflector will melt, and other materials such as refractories may be more suitable for the deflecting surface.

To provide data for the design of uncooled efflux deflectors, a heating rate investigation of the Blue Streak installation at Woomera has been carried out theoretically and experimentally. The heat transfer coefficient and stagnation temperature at the efflux deflecting surface are calculated theoretically with the aid of model test results. Heat transfer coefficients derived from temperature measurements on steel plates embedded in the deflecting surface are compared with the theoretical results. It is concluded that simple aerodynamic heat transfer theory can provide an effective engineering estimate of the temperature rise of an efflux deflecting surface.
Buckling of 45° Eccentric-Stiffened Waffle Cylinders
Authors: Meyer R. R.
Published: July 2016

The cylindrical tankage which forms part of the primary structure of missiles and space vehicles may be subjected to high compressive axial and bending loads. Since allowable compressive stresses for monocoque construction are generally low because of small bending rigidity and sensitivity to geometric imperfection, it is advantageous to use some type of wall stiffening. One such choice is the integrally milled-out 45° waffle. This consists of a square gridwork of ribs which form 45° helices over the cylindrical surface. The panel is generally milled out in the flat and then bent up to form a circular cylinder. An advantage of the 45° construction is the exclusion of buckling modes between hoop reinforcement; such modes are frequently critical for the 0° to 90° type of stiffening.
The Role of Private Enterprise in British Air Transportation
Authors: Williams J. E. D.
Published: July 2016

It is a great honour to be asked to give the Barnwell Memorial Lecture. It is now nearly 29 years since Barnwell was killed test flying at the age of 57 an aeroplane which he designed and built himself. He was a man of many parts and a man for all seasons. It is a measure of the passing years that now there is a Barnwell Memorial Lecturer who did not enter aviation until three years after Barnwell's death and has never participated in the design of any aircraft. Yet Barnwell's ideas and actions have indirectly, anonymously and through others, had important effects on the life and work of myself and thousands of people like me. I did my operational flying in the last World War on Beaufighters, and in more recent years have been concerned with Britannias, both aircraft designed and built in Bristol by members of Barnwell's old team. It is curious to note that exactly 50 years ago Barnwell was sitting on a committee of the Royal Aeronautical Society charged with considering the future of the Society. We are still at it. At a meeting of the Future Activities Committee the other week, I wondered what Barnwell would have thought of the discussion and recalled Isaac Newton's remark that if we now see a little further it is by standing on the shoulders of giants.
Some Approximate Formulae for Transient Temperature Prediction in Aircraft-Type Structures
Authors: Johns D. J. , Wooldridge M. J.
Published: July 2016

The solution of the general heat transfer problem for typical aircraft-type structures usually involves a finite element approach involving the solution of a large number of simultaneous equations. This may be performed by calculation using a digital computer or with an analogue simulator. For calculations involving both spatial and time intervals considerable care must be exercised to obtain solutions which are not divergent or oscillatory and this usually involves very small time increments and a large total computation time.
On a Simplified Technique for the Determination of the Dynamic Properties of a Linear System with Damping
Authors: Nissim E.
Published: July 2016

The experimental methods in current use for the determination of the dynamic properties of an arbitrary finite-freedom system are based on restrictive assumptions which may often be of questionable validity. The most common assumption is that the damping matrix can be reduced to a diagonal form by a congruent transformation using the modal matrix of the undamped system. Further, the damping is normally assumed to be hysteretic, or light if viscous.

Bishop and Gladwell give an excellent account of the theoretical background of the present experimental techniques. These can be divided into three groups:

1.

The method of Kennedy and Pancu which obtains experimentally the complex receptance of the system and extracts its dynamic properties from vectorial plots.

2.

The method of Trail-Nash and Asher which is based on the experimental determination of the in-phase response of the system and requires computation to be incorporated with the experimental procedure.
Compressible Shear Flows in the Duct with Varying Cross-Sectional Area
Authors: Fujii S.
Published: July 2016

The basic theory of the compressible non-swirling rotational flows through ducts with varying hub radii, associated with the concept of actuator discs, is described. The problem is simplified by considering a single-parameter in the radial velocity profile. Particular attention is given to the combined effects of the taper of inside walls and also of compressibility on the radial velocity and the axial velocity profile. The derived ordinary differential equation with non-homogeneous terms can be reduced to the well-known formula of classical actuator disc theories for the cylindrical passage. A numerical example is also presented.
The Future of Rotorcraft and Hovercraft
Authors: Mensforth Eric
Published: July 2016

It is a privilege to pay tribute through this Cierva Memorial Lecture to a great pioneer and an honour to do so in this, the Society's Centenary Year. In 1918, when 24 years of age, Cierva designed and built a three-engined aeroplane which stalled during a turn and, after spinning, crashed. He recognised the limitations of the conventional aircraft and turned to the rotating wing.

Westland's association with rotary wings began with the five-seater 600 hp Cierva C.20, built in 1934. Their first series production rotorcraft, the S.51, to the design of Igor Sikorsky, came some 14 years later. With the passage of further time, bringing some successes and some frustrations, a sound foundation has indeed been laid for future progress.
The Society of British Aerospace Companies Ltd
Authors: Goodinge H. W.
Published: July 2016

On 29th March of this year, The Society of British Aerospace Companies celebrated the completion of fifty years' activity. It was on 29th March 1916 that The Society of British Aircraft Constructors was incorporated —junior to The Royal Aeronautical Society and The Royal Aero Club, but senior by two years to the Royal Air Force. The Society continued under that title until 26th February 1964, when its name was changed to “Society of British Aerospace Companies.” The new title retains the well-known initials SBAC but more accurately covers the wide range of interests of the Society's Members—not only the manufacture of aircraft, but of engines, missiles, electronics, hydraulics and pneumatics, electrical equipment and all other components and materials essential to such a technologically advanced industry. The new title also brings the Society into line with comparable associations in the United States, France, Germany, and Italy.
The Steady Flow Through a Cascade of Closely Spaced Circular Cylinders
Authors: Roberts B. W.
Published: July 2016

Two recent papers by Bradshaw have drawn attention to instabilities in the flow through wind tunnel screens. In Plate 1 of ref. 2 a smoke tunnel photograph shows the manner in which the jets coalesce behind a high blockage, two-dimensional cascade. In the present note, three points relating to this flow will be discussed.
Recent German Contributions to Research in Thermogasdynamics of Aerospace Propulsion Systems
Authors: Quick A. W.
Published: July 2016

After some introductory remarks about Reynolds and Prandtl the results of some work in the field of the aerodynamics of propulsion plants will be described. In this context there are, first, cascade flows in which the influence of such parameters as Reynolds number, Mach number, axial pressure ratio, turbulence and boundary constraint have been studied. Investigations in the transonic and supersonic ranges will also be considered.

Flows with heat addition at both subsonic and supersonic speeds are then dealt with, including reaction-kinetic effects in the ignition of fuel and in the recombination processes in expanding jets.

The flow problems which arose in the development of the rocket test beds for the third stage of the ELDO rocket will be described and, in particular, the special rocket steam generators and flow problems associated with the strong cooling of the hot rocket gases will be discussed.

Next we shall deal with work on the flow processes in the acceleration of electrically-conducting gases. Some results are described of the self-magnetic—the Hall current—and the electrodeless electromagnetic acceleration.

Finally some problems of measurement techniques will be touched on.
Siting Considerations for Aircraft Static Dischargers
Authors: Cooper C. E.
Published: July 2016

Various natural phenomena can result in sufficient difference of potential between an aircraft in flight and its very rapidly changing surroundings that, immediately adjacent to the aircraft extremities, there will exist potential gradients high enough to produce local atmospheric ionisation or “corona”.

Since there is no effective method known to prevent the development of these potential differences, aircraft are commonly fitted with a number of so-called “static dischargers” or “neutralisers” to control the nature and occurrence positions of the corona in such a way as to minimise the generation and radiation of RF noise, which would otherwise be quite capable of causing complete mis-function of navigational aid systems.
Some Aspects of International Collaboration Between Bristol Siddeley and SNECMA
Authors: Smith G. T.
Published: July 2016

International collaboration can mean many different things depending on its context. It has been applied over recent years to almost every international activity from licence manufacture to joint design and development projects and in each case, although some features are common, there are unique difficulties and problems to be solved.

One of the most important aspects of international collaboration is that currently being practised between sections of the aircraft industries of the United Kingdom and France and, in particular, the following joint ventures of aircraft and engine design and manufacture
The Management of Cost Reduction-Method or Myth?
Authors: Davies H.
Published: July 2016

“When I use a word”, Humpty Dumpty said in a rather scornful tone, “it means what I choose it to mean—neither more nor less.” Lewis Carroll's words could hardly be more appropriate than to the expression “Cost Reduction” as used by the businessman. To some, cost reduction appears as a game played with imaginary money to earn “brownie points” to please a customer. To some in organised labour, the words are viewed in the same generic class as “sweat shop” and “scab”. To others, however, cost reduction seemingly implies a business discipline exercised in earnest and to be reflected in the company balance sheet. The question then, may well be asked, “What is cost reduction?“—“Is it possible to provide a meaningful management technique to motivate cost reduction activities and to measure the results?“
The Training of Test Pilots
Authors: Watts R. A.
Published: July 2016

“Learn to Test. Test to Learn.”which succinctly state the task of the student and the graduate test pilot, were selected in 1953 as the most suitable inscription to place under the Armorial Bearings of the Empire Test Pilots’ School. This small Unit, which was formed in 1943 at the Aeroplane and Armament Experimental Establishment, Boscombe Down, has, over the past 22 years, provided the formal training necessary to enable test pilots to meet the requirements of the Flight Test Establishments of the Ministries of Aircraft Production, Supply and Aviation. During this period the School has trained some 595 test pilots, 34 per cent of whom have come from 26 Commonwealth and Foreign Air Forces.
A Brief Review of Wind Effects on Buildings and Structures
Authors: Scruton C.
Published: July 2016

Present day structural forms and methods of fabrication have considerably increased the importance of wind as a design consideration. For estimations of the overall stability of a structure and of the local pressure distribution on the cladding, a knowledge of the maximum steady or time-averaged wind loads is usually sufficient. Mind tunnel tests to determine the wind loading coefficients are often made in smooth uniform flow, but for more accurate data account must be taken of the effects of the vertical gradient of wind speed and the turbulence of natural winds. Further research is needed into these effects and also into methods of obtaining a sufficient representation of the natural wind in the wind tunnel.

There are a number of ways by which wind excites structures into oscillation; among these are vortex excitation, galloping, proximity effects including buffeting, stalling flutter and classical flutter. The vortex and galloping excitation might be expected to be especially sensitive to the turbulence properties of the air flow. Also, in the absence of any mechanism for instability, atmospheric turbulence may directly excite oscillations through the random forcing by the pressure fluctuations which it produces. Further understanding of this problem must come through research into the effects of turbulence (and to the extent to which these effects may be disregarded), but the range of the conditions is so vast and complicated that it seems unlikely that sufficient aerodynamic and wind data will be accumulated to permit the response of a proposed structure to be calculated with reasonable certainty, and for major projects it is anticipated that comprehensive tests on aeroelastic models in wind tunnels with appropriate turbulent air flow will continue to offer the more reliable predictions.

The air flow around buildings is of concern inasmuch as it influences the dispersal of combustion and other gases from the smokestack and also in its effect on the speeds and turbulence of the wind over areas used by pedestrians. The erection of a tall building may cause an increase in wind speeds and gustiness at ground level. These problems of the external flow over buildings are readily examined in wind tunnels. For this purpose tunnels with large working sections are desirable to permit a sufficiently wide area of the neighbourhood to be represented.
The Drag Due to Lift of Plane Wings at Subsonic Speeds
Authors: Gardner D. , Weir J.
Published: July 2016

This note outlines a method for the prediction of drag due to lift of plane wings at Mach numbers below drag divergence and Reynolds numbers above 106. The method is based on the correlation of a number of wind tunnel measurements in terms of the effect of viscosity on lift curve slope. A comparison is made of the accuracy of estimating the induced drag factor, k, using this method, with the method of ret. 1, and it is shown that considerable improvement has been made, and that, in general, the predicted value of k is within 10% of experiment.
Blockage Corrections for Blunt-Based Bodies of Revolution
Authors: Calvert J. R.
Published: July 2016

Maskell has developed a theory for the blockage effects of bluff bodies in a closed wind tunnel and has shown that it gives good results for flat plates normal to a stream. For streamline bodies there are well established methods of calculating the corrections, but for long bodies with blunt bases it is not obvious what method should be used.
Relationships Between Government and Aeronautics–A Discussion
Authors: Haviland Denis W. G. L.
Published: July 2016

A Discussion on the Relationships between Government and Aeronautics was held at the Society on 4th November 1965 with the President, Sir George Gardner, KBE, CB, HonDSc, FRAeS, in the Chair. Short introductory papers were given by Mr. Denis W. G. L. Hayiland, General Robert Lecamus and Brigadier General Ake Sunden. Introducing these principal speakers Sir George said how fortunate the Society was to have persuaded three such eminent people to open this Discussion; they were particularly grateful to their French and Swedish colleagues. General Sunden had graduated as an engineer and had been a pilot since 1934. He had served in a number of commands and had been a flying instructor and a test pilot. He was now a member of the Board and Director of Aircraft, Royal Swedish Air Force Board, which included responsibility for aircraft, armament, aero engines, airborne electronics and test flying.

General Lecamus was also an engineer and a pilot; he had served as an engine specialist in various duties, including three years as Head of the Engine Test Section at the French Test Flying Centre at Bretigny. In 1948 he had joined Direction Technique des Industriel Aéronautiques (DTIA) (which later became DTCA—Direction Technique des Constructions Aéronautique) as Deputy Chief of the Development Department and later had served as Chief of Inspection Services in Toulouse for the South West of France. He was now Director of DTCA.

Mr. Haviland had served throughout the 1939-45 War in the Army but he also had learned to fly. After the War he had been Principal, Control Office for Germany and Austria, becoming Assistant Secretary; in 1951 he transferred to the Ministry of Supply becoming Under Secretary, and from 1959-64 was Deputy Secretary, Ministry of Aviation. In 1964 he had joined Industry and was now Chairman and Managing Director of Staveley Industries Ltd.
A Manufacturer's Viewpoint
Authors: Laight B. P.
Published: July 2016

What I talk about relates to an experience on military aircraft produced for our own Services under the working arrangements which were then usual.

We have heard that the Services are finding that unreliability is taking too much of their time and money and could impair their fighting efficiency. I think that this situation is well understood by aircraft constructors, and that there is a real desire to improve the situation and to do whatever can usefully be done. But it is not easy to quantify the subject of reliability, and some of the approaches which have been suggested for improving reliability do not seem feasible to me.
Note on the Prediction of the Local Flow Conditions at the Crest of an Aerofoil Section in a Sonic Stream
Authors: Thompson N.
Published: July 2016

The pressure distribution on the surface of an aerofoil section at near sonic speeds is not sensitive to small changes in free-stream Mach number, and the distribution at M0=1.0 is often referred to as the sonic-range pressure distribution. Attempts to predict this form of pressure distribution have met with some success in the past, the work of Spreiter and Alksne, using an approximate solution of the non-linear equations of transonic small-disturbance theory, being of particular note. Reference 1 demonstrated the application of this theory to a family of non-lifting, sharp-nosed aerofoils and found good agreement with experiment at free-stream Mach numbers close to unity.
A Review of Panel Flutter at Low Supersonic Speeds
Authors: Johns D. J.
Published: July 2016

It has been shown both experimentally and theoretically that the Mach number range from 1·0 to 1·5 is very critical for panel flutter. Also, the correlation between experiment and theory in the above range has generally been poor.

Sufficient papers have now been written which are relevant to the title subject that it is possible to make a review of the subject and to make recommendations for further work. These papers are reviewed in approximate chronological order. In all cases the panels referred to are rectangular and unswept with the air flow on one side only, unless otherwise stated.
Centre of Pressure of Cowl Shapes Having Minimum Drag in Supersonic Flow
Authors: Carey D. J .
Published: July 2016

Formulae are presented giving the centre of pressure of axi-symmetric bodies at zero incidence having profiles for which the drag is a minimum in Newtonian flow.

Boyd has suggested that a close correlation may exist between such profiles, and profiles derived from exact pressure distributions, in supersonic flow.
Computerised Diagonal Tension Analysis
Authors: Robinson John
Published: July 2016

Diagonal tension analysis of flat panels in shear is commonplace in aircraft design; such an analysis is presented in detail in the Royal Aeronautical Society Structures D.S., 02.03 series. In their present form, although well presented, they are time consuming and laborious to the engineer. It is therefore desirable to transform these data sheets into a form which can be easily programmed for solution by computers. The aim of this paper is to present such a format. The method is adequately covered in the data sheets, but important points are listed here. A step by step procedure for the analysis is given with a suggested programme input sheet and output format. An example is given with corresponding output data to be used for programme check-out purposes.
Aeronautical Research at the University of Southampton
Authors: Richards E. J.
Published: July 2016

F. W. Lanchester obtained his first technical education at the Hartley Institute in Southampton, later to become the University of Southampton, during the years 1886–89. His autobiography describes in vivid terms the primitive nature of the workshop and apparatus available. He would indeed be shocked at the wealth of modern equipment now encountered in engineering departments of a University. At the same time, no one can possibly say that this lack of equipment influenced his pioneer spirit or his extraordinary clarity of thought, not only in the fields of aeronautical and automobile engineering, but also in subjects as diverse as the musical scale, poetry and even relativity.
Lift Turbo-fans
Authors: Wilde C. L. , Coplin J. F.
Published: July 2016

In the past decade many powerplant systems have been proposed for VTOL aircraft. Of these, flight tests have shown the lift jet and vectored thrust engine to be practical and suitable for forming the basis of operational VTOL military strike aircraft. High on the list of proposed VTOL powerplant systems is the lift turbo-fan which has the inherent advantages of better hover fuel consumption, lower efflux velocity and lower jet noise. So far there has been no practical demonstration of this type of powerplant in Europe, and it is useful to look at some of the studies that have been made to compare the characteristics of the lift fan and the lift jet.

The paper compares the Rolls-Royce RB 162 16:1 thrust/weight ratio lift jet and its installation with a range of Rolls-Royce lift fans derived from the RB 162 using the latter as the gas generator.

The comparisons between the basic engines reveal the fan to have worse thrust/volume, thrust/weight and response rates. The installation of these engines in a lift pod is fully described showing the equipment required for complete VTOL powerplant. A comparison of the Installed weight breakdown for the two types of pod is made. Some of the advantage of the fans’ inherently lower fuel consumption is lost in the longer take-off transition time which accrues from the higher momentum drag of the lift fans and higher pod drag.

Looking to the future, the authors suggest fan engines based on more advanced gas generators and having a greater degree of ingenuity to minimise the weight and volume penalties.
Boost-Glide Vehicles for Long Range Transport
Authors: Ashford D. M.
Published: July 2016

Boost-gliders offer the possibility of rapid long distance travel (e.g. England-Australia in 75 minutes) and boosters using similar technology offer the possibility of “everyday” travel between the earth and space stations. This paper uses simple parametric methods to assess conditions for boost-gliders to be commercially competitive and to discuss their evolution in relation to other boosters and advanced aircraft. It is concluded that booster-gliders using a similar state of the art to presently-projected aerospace transporters (i.e. winged, two-stage, hydrogen-fuelled vehicles) would be reasonably economical given cheap hydrogen fuel and a market large enough to support about 50 aircraft each making 5 antipodal flights per day. In addition, numerous problems would be involved in developing this type of vehicle to an acceptable level of design and operational familiarity but, at first sight, none of these appears to be insurmountable.
The General Requirements of the Three US Armed Services for Helicopters and Other VTOL Aircraft
Authors: Hewin Larry M.
Published: July 2016

It is necessary at the outset to discuss the limitations that are imposed by (1) the security classification normally attached to approved requirements and (2) the inter-relationship of technology and the establishment of formal requirements.

“Military requirements” may be defined broadly as formally stated military needs that are considered technically obtainable at reasonable cost in a specified time period. The required and obtainable performance will normally be classified as security information, as will the details of the intended concept of military operation and application. Hence, it is possible to deal with the subject only in a rather generalised manner.
The Influence of Attached Boundary Layers in Determining the Optimum for Blades in Cascade
Authors: Allan W. K. , Stratford B. S.
Published: July 2016

Dr. Stratford (p. 133, February 1965 Journal) is to be supported in his endeavour to apply boundary layer theory to the prediction of optimum loading requirements in flow through blades in cascade. Inevitably some simplification of the general flow system in a blade passage is necessary if undue complexity is to be avoided. In the simplified flow model, however, care must be taken to avoid over-simplification, and the limitations imposed by legitimate approximations must be appreciated.
Fifth Cierva Memorial Lecture
Authors: Henrich Focke E. H.
Published: July 2016

I Have the great honour to give the Fifth Memorial Lecture in tribute to Juan de la Cierva, a great man and pioneer in rotating wing development, whose work was predominantly done in England.

His fundamental practical achievement, resulting from a deep knowledge of aeronautical science, was the demonstration of the fact that a big airscrew with suitable pitch could serve as a lifting surface without the danger of stall which is inherent in fixed-wing aircraft.
Low Speed Handling of a Slender Delta (HP115)
Authors: Henderson J. M.
Published: July 2016

The title of this lecture is a little misleading in that the intention is to give broad coverage not only to the handling qualities of the aircraft, but also to some of the general information and lessons derived from the flight-testing, some of the background and some of the supporting work. Attempts will be made to correlate some of the characteristics with shapes that are generally regarded as less radical. Only limited attempts will be made to cross-read to larger applications of the slender delta, not because of absence of cross-read, but because this is an activity which must not be undertaken lightly or ill-advisedly, and is within neither the time-scale nor the scope of this lecture.
Transition Due to Roughness
Authors: Head M. R.
Published: July 2016

It is commonly stated in the literature on laminar flow control (see, for example, ref. 1) that the important parameter controlling the height of tolerable roughness is the Reynolds number per foot, or unit Reynolds number, Vh; provided this parameter is the same in any two cases (which are closely geometrically similar) then it is assumed that the tolerable roughness height will also be similar. It is the object of the present note to point out that this is true only in very restricted circumstances and that in general the actual physical scale is also of considerable importance, as the following shows.
Scheduling of Commercial Air Movements: The Airline Point of View
Authors: Watts R.
Published: July 2016

The Airline is satisfying a demand, a demand for transportation. Such transportation is not something in itself—people do not simply go for the ride—but is part of a bigger demand. The airline attempts to create, stimulate and, to some extent, change this demand by tariff and other means but nevertheless it is attempting to satisfy a naked demand as it arises. If the demand is for 8 a.m. out of Glasgow, we as an airline—contrary to popular opinion— attempt to satisfy the demand at that time within the overall context of profitability. In a competitive situation—and this includes competition with other forms of transport, not simply air, as well as other forms of consumer expenditure—the airline's ability to take of this demand what suits it and ignore the rest, is strictly limited. The success of an airline depends upon the efficiency with which it satisfies this demand.