bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Brief Review of Wind Effects on Buildings and Structures
Authors: Scruton C. 
Published: July 2016

SummaryPresent 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

SummaryThis 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.
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.
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.
Lift Turbo-fans
Authors: Wilde C. L. , Coplin J. F. 
Published: July 2016

Summary: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

SummaryBoost-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.
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.
Eurocontrol—A European Organisation Its Structure and Future Prospects
Authors: Bulin R. 
Published: July 2016

On receiving an invitation from your distinguished Association to come and speak to you about EUROCONTROL, I was most pleased and honoured. I am glad to be able to represent our Organisation and in the name of the Organisation I wish to thank you most warmly.Before this gathering of legal experts I, as a technician, would fear to be presumptuous if I did not feel that nowadays no progress is conceivable without close collaboration between the legal and the technical. It is with this thought in mind that I shall lay before you some of the technical reasons which led to the setting-up of EUROCONTROL, the operation, the structure, the achievements and the future prospects of this new European Organisation for the safety of air navigation.
Note on a Generalised Velocity Parameter in Two-Dimensional Fluid Dynamics
Authors: Cohen M. J . 
Published: July 2016

The purpose of this note is to draw a formal parallel between the fundamental hodograph flow equations in subsonic and supersonic regimes when expressed in terms of a generalised velocity parameter. This parameter can cover, by simple algebraic extension, hodograph flows in either regime; it has simple geometrical and dynamical interpretations and models of the combined hodograph plans in terms of this parameter are also suggested.A similar, and perhaps familiar, velocity parameter appears to have been first used in the solution of certain subsonic flow problems by Tsien, following a suggestion of von Kármán, although a more general and basic form was not described.
Boundary Layer Transition Measurements Using a Surface Hot Film Downstream of Distributed Roughness at Mach Numbers from 1·3 to 4·0
Authors: Mabey D. G. 
Published: July 2016

SummaryA surface hot film was used as a boundary layer transition indicator on wind tunnel models at Ifiach numbers from 1·3 to 4·0. The results illustrate the difficulty of fixing transition with distributed roughness on small models at supersonic speeds.
RAE Guided Weapon Test Vehicles in the 1950s
Authors: Smith T. L. 
Published: July 2016

SummaryA test vehicle, in the G.W. sense is a body used in free flight to test components, structures, aerodynamics, servo controls, guidance systems and propulsion. The body may have weapon-like characteristics or may be designed purely to investigate a particular phenomenon or theory which has a bearing on the design of weapons. From the inception of the G.W. Department this work was given an important place in the programme and played a major part in laying the foundation of knowledge and experience on which the G.W. work in this country was built. Two early test vehicles were CTV.1 and KTV.1. CTV.1 was used for a good deal of aerodynamic investigation, together with the development of free flight instrumentation and measurement techniques, it was our first “beam rider”, and was also used in a command guided role. The beam riding work was done in co-operation with TRE who were responsible for the guidance aspects of CTV.1. RTV.1 was a larger vehicle used mainly on beam riding guidance research. A later version was used in a vertically launched role to study launching and stability problems preparatory to the Black Knight work. The CTV series culminated in CTV.S which itself took various forms. The CTV.S Series I was designed for aerodynamic measurements on a coasting dart at high incidences and therefore high altitude. CTV.S Series 2 was designed for kinetic heating investigations while CTV.5 Series 3 was an upper atmosphere sounding rocket, later known as Skylark and still providing a valuable service. RTV.2 was designed for further work on liquid fuel propulsion and semi-active radar guidance research and was developed further to become the better known GPV. An interesting method of recovery from the sea was developed for this vehicle. With the requirement for ballistic missiles and satellite launchers a whole new field of work on missile structures, stability, control and guidance was opened up. This called for the development of the latest and very successful test vehicle, Black Knight.
Licensing British Air Transport
Authors: Wheatcroft Stephen 
Published: July 2016

It is probably not necessary for an economist to justify his temerity in addressing the Air Law Group of this Society on Licensing since I am here by invitation. But it is worth noting that a great deal of air law is, in fact, concerned with the economic regulation of the industry: the law is endeavouring to give effect to conclusions about how best to arrive at certain economic results.I shall not discuss any details of the law relating to air transport licensing: I shall concern myself with the broad economic issues which underlie the law. I shall start from first principles and ask “Why should we regulate air transport?” and, if there are good reasons for so doing, “what are the essentials of a regulatory system?”.
Experiments which Disproved the Theory of Intercrystalline Corrosion of the Light Alloy Duralumin
Authors: Short Hugh Oswald 
Published: July 2016

The German metallurgists were the first to discover how to make the light alloy of aluminium which they called duralumin. I understand it is a mixture of 97 per cent aluminium and 3 per cent copper, but it may have a very small percentage of rarer metals. Whereas aluminium has a yield point of about nine tons per square inch, duralumin has a yield point of twenty-five tons per square inch.Before and during the First World War the German aircraft constructors used duralumin in the construction of Zeppelin rigid airships, aeroplanes and seaplanes and flying boats. Towards the end of the First World War, I began to fear that the Germans would invent all-metal aircraft with highly streamlined forms which would increase the speed of their aircraft and that at very high speed with their bombing aircraft, they would fly at almost house top level, drop a time bomb on our works and be at a safe distance before the explosion occurred.
Agricultural Aviation Potentials for Asia
Authors: Little E. C. S. 
Published: July 2016

This contribution to the proceedings of the Agricultural Section of the Society is intended: —(a) To describe a problem in agricultural logistics which when solved should help developing countries in Asia to increase their food production, especially of rice.(b) To suggest that the problem could be solved from the air.(c) To offer some layman’s suggestions as to methods by which aircraft and associated installations might be designed and organised to meet the special situation to be found in Asia. From professional advice on these suggestions it is hoped that a workable plan may be devised, and the necessary finance provided from Government or commercial sources to carry out the necessary research and development.(d) If a workable plan can be devised it is hoped that one or more of the countries which might benefit would wish to accept any assistance offered and to co-operate in the arrangements necessary.(e) While the observations in this paper are believed to be generally applicable to the flat rice-growing monsoonal areas of Asia the ideas have been derived from working experience (for three years) in only two of these countries: Burma and E. Pakistan.
Maintenance and Overhaul in Relation to Operators’ Field Requirements and Official Airworthiness Requirements
Authors: Best-Devereux H. 
Published: July 2016

The agricultural aircraft is a special vehicle with special needs for simplicity in design coupled with interchangeability and accessibility of components and equipment. Cheap price, commercial availability and easily maintained equipment of high reliability, field replacement capability, freedom from the need of special tools and rigs, together with lack of complication, reflect markedly in the economics of operation and provide improved safety in operation.To establish that these parameters are appreciated and allowed for, it is profitable to consider whether operators themselves give adequate and logical thought to engineering problems in their forward planning, and whether aviation legislation permits an adequate projection of this philosophy rather than reducing true airworthiness, true safety levels, and reasonable economics.
Comment on the Effect of Proof Stress on Notched Fatigue Strength
Authors: Welbourne E. R. 
Published: July 2016

In his note, Forrest compares the results of an experimental investigation of the notched fatigue strength of HE 15 aluminium alloy (L.64/L.65 type) in three conditions of heat treatment with predicted values obtained using the analysis by Gunn. This analysis appears in R.Ae.S. Fatigue Data Sheets A.00.01 and .02.The analysis requires a minimum knowledge of four parameters, Kt’ the elastic stress concentration factor, ft the tensile strength, ƒp the 0·1 per cent proof stress and Sao the fatigue strength under reversed loading for the specified endurance Ncycles.
Effect of Third Harmonic Vibratory Force on a Linear Spring-Mass System
Authors: Kirk C. L. 
Published: July 2016

SummaryThe response of an elastic system having a single degree of freedom, to a vibratory force whose waveform can be varied, is examined. The variable waveform is produced by a system of two pairs of unbalanced rotors in which one pair rotates at three times the speed of the other pair. The waveform depends on the frequency of excitation, the phasing of the rotors and the ratio of their amounts of unbalance. If the rotors are run at a speed at which the faster pair rotates above resonance while the slower pair rotates below resonance, a frequency is found at which the rate of change of amplitude with respect to frequency is zero. At this point, however, the waveform is quite sensitive to small changes in the frequency of excitation. If the rotor speeds cannot be maintained constant, and if stable vibration waveforms are required, it is necessary to run the slowest rotor well above the resonant frequency where both the amplitude and waveform will be virtually independent of frequency.
Materials
Authors: Fielding J. 
Published: July 2016

The Materials Engineer should provide materials of proven integrity with the highest possible strength to weight ratio. This paper discusses the potentialities with the basic materials used for airframes. Attention is directed mainly to materials for subsonic aircraft.It will be helpful to consider the distribution of materials in present day aircraft, and Fig. 1 shows clearly that the basic airframe materials at present are aluminium alloys and steels.
Factors Affecting the Surface Temperature of a Hypersonic Aircraft
Authors: Sinnott C. S. 
Published: July 2016

SummaryIt is shown that by combining the dependence of boundary layer heating on local flow conditions with the lifting characteristics of hypersonic wings a simple relationship between wing loading and surface temperature can be derived. This replaces the common concept of an altitude/Mach number flight corridor through which hypersonic flight appears possible without exceeding an acceptable surface temperature, and indicates that flight beyond Mach 6 will in fact require considerable material or cooling developments.
Effect of Shock Boundary Layer Interaction on Aerofoil Pressure Distributions at Transonic Speeds
Authors: Tirumalesa D. 
Published: July 2016

SummaryA method of improving pressure distributions predicted by inviscid theory over two-dimensional aerofoils at transonic speeds taking into account shock-wave turbulent boundary layer interaction as obtained in the case of the flat plate is described.The method was applied to a non-lifting circular arc aerofoil of eight per cent relative thickness. The shock wave location, pressure distribution and drag coefficient were calculated and compared with experimental and inviscid theoretical results.It has been found that the method gives results which are consistent with experimental results in various aspects.
The Estimation of the Non-Linear Lift of Delta Wings at Supersonic Speeds
Authors: Squire L. C. 
Published: July 2016

Summary:Up to the present most of the methods used to calculate the flow over delta wings with leading edge separations have been based on slender wing theory. In this paper one of the simplest of these methods is carried over to linear theory and the overall lift calculated. In general the results are in agreement with experiment, in particular both show a fall in nonlinear lift as the leading edges of the wing approach the free stream Mach angles. The discrepancies which exist appear to arise mainly from the use of linear theory rather than from the mathematical model introduced to treat the separated flow.