bluuebunny/crossref_metadata_2025_split huggingface dataset:
An investigation of the grid fins as control surface devices for missiles
Authors: Chen S. , Khalid M. , Xu H. , Lesage F. 
Published: July 2022

AbstractRecently, grid fins have been receiving increasing attention as a practical and efficient means of controlling missile trajectory. Preliminary studies at IAR have demonstrated that modern CFD methods can be used for computing flows past complex grid fin type configurations, and that these methods are more soundly physically based than the earlier vortex lattice and/or shock expansion methods.The current paper addresses the issue of the grid fin size, in terms of both the panel thickness and the frontal shape. The study covers three thicknesses for the grid fin panel, with front shapes having a simple blunt square face, as well as a sharp knife-edge shape. In addition, an important aspect of the present investigation is to quantify the aerodynamic effect of the ramp fairing installed immediately upstream of the blunt base upon which the grid fin assembly resides. A comparison of flow field characteristics and aerodynamic coefficients of the grid fin assembly, with and without the fairing ramp, would provide a direct means of evaluating the effect of the ramp. At this stage, the investigations are based on Euler calculations. The present study focuses on a standard grid fin configuration mounted on a generic cylindrical body.
The Cranfield aircraft handling qualities rating scale: a multidimensional approach to the assessment of aircraft handling qualities
Authors: Harris D. , Gautrey J. , Payne K. , Bailey R. 
Published: July 2022

AbstractThe Cooper-Harper scale is currently the only well-established scale for assessing aircraft handling qualities. However, as a result of having a unidimensional format the Cooper-Harper scale lacks diagnostic power and has also been criticised for exhibiting poor reliability. The Cranfield Aircraft Handling Qualities, Rating Scale (CAHQRS) is a new, multidimensional rating scale using concepts from two established scales, the NASA-TLX workload scale and the Cooper-Harper scale. This paper provides an overview of the development of the CAHQRS and the results from a series of validation trials in an engineering flight simulator. An in-flight refuelling task and an approach and landing task using a range of control laws were used in these evaluations. The results showed that the CAHQRS had high positive correlations with the Cooper-Harper scale. However, the CAHQRS also demonstrated greater validity, diagnostic power and higher test/re-test reliability than the previous scale.
Inertial navigation and its impact on future avionics systems
Authors: McKinlay W. H. 
Published: July 2022

It is now over twenty years since the first experimental inertial navigation system was built and tested in America, by MIT. Over that period inertial navigation has come of age as a technology, and many thousands of inerital systems are in service in civil and military aircraft.Ferranti Limited have been active in this field over 15 years, developing and producing both the basic inertial instruments and complete systems for a range of aircraft and space applications. The first system was produced for the TSR-2, which was cancelled at the prototype stage. But a first generation production system has now been in RAF service for some time. A second generation system, now at an advanced stage of test and development, will equip the European Multi Role Combat Aircraft (MRCA). A version of the same system has been adopted in Japan.
A view of air freight developments in the next decade
Authors: Olason M. Lynn , Reynolds A. Dean 
Published: July 2022

The purpose of this paper is to provide a view of air freight developments over the next decade.Before we try to do that, it might be very useful to look back over the past 10 or 15 years to see where we are and to develop some understanding of how we got into the position that we find ourselves in today. Therefore, we are going to go back over the past 15 years and review the economic situation and assess the impact of selected air freighters in an attempt to develop some guidance in forecasting what we might look forward to in the next 10 years.
Rewards and penalties for suppliers of equipment
Authors: Passey R. D. C. 
Published: July 2022

Over the years, the evolution of legal and contractual relationships between the suppliers of equipment and their customers has been fragmentary. Fiscal incentives for the supply of economical equipment have been rare, while incentive contracts for developing military equipment have been the cause of some controversy, particularly as regards allowances for inflation.Immediate interests have tended to take precedence over longer term characteristics, which are often of more importance to customers. Relative merits of rewards, penalties and other motivating factors have received little attention in the literature, and philosophical considerations have been neglected.
Engineering and development problems of Spacelab
Authors: Hoffmann H. E. W. 
Published: July 2022

In the past thirty years the exploration and exploitation of space has been one of the few new eras into which man has penetrated and opened a new frontier. Naturally, this drive was made by the two world powers which possess the resources and which are pushed by their competitive fight for public prestige and world-wide admiration. Once again Europe supplied many of the ideas and many of the leading people. And what did we do for ourselves?In the beginning of post Second World War space activities we missed the start. The first satellites were already in orbit when the first space activities in Europe were proposed. But when we began to move in 1961 we began to move in the right direction. For our purpose the essential factor was the creation of the European agencies—ELDO and ESRO at that time—in which the national efforts of the member states were combined and co-ordinated towards the common goal.
Hybrid computation in aeronautical engineering
Authors: Greene K. R. 
Published: July 2022

Many engineering problems are unsuitable for either pure digital or pure analogue computation. An example is provided by the helicopter. Owing to the size of the problem, a digital solution takes too long, and far more equipment is required than is generally available on analogue computers. In addition, there is the difficulty of including important non-linear effects.A hybrid computer is a combined digital and analogue computer and can be used to advantage in these circumstances. I shall mainly be concerned with the integration difficulties which arise when applying this form of computation to helicopter simulations. The concepts developed are not restricted to the helicopter problem and an integration technique will be explained which has wide application in the study of other engineering systems.
V/Stol developments in Hawker Siddeley Aviation Limited
Authors: Brennan M. J. 
Published: July 2022

At the beginning of manned flight, aircraft needed some length of ground run in order to take off and fly. The Wrights took under 60 ft, and with a wing loading of 1.47 lb/sq ft and a CL max of approximately 0.9 they achieved first manned flight.Time went on, and man grew more familiar with the hazards of increased take-off length and take-off speed. His growing knowledge of aerodynamics allowed him to increase the CL max values on wings. These facts combined to allow him to use increased wing loadings to improve his flight efficiency in terms of payload, cruise speed and range. The following graphs show the growth of these characteristics.
An independent view
Authors: Wood J. C. 
Published: July 2022

Any assessment of industrial relations must start with consideration of the character of the industry in question. It would be, for example, impossible to understand the behaviour of the modern miner without some knowledge of the history of the coal industry. Aviation has only a brief history. It nevertheless has a flavour of its own.Three distinctive features are of note. To the outsider it is clear that the aviation industry brings with it the sort of challenge which appeals to the enterprising and the romantic. It is therefore no surprise that the industry has more than its fair share of strong character. There exists an independence of outlook on both sides of the industry which is not always easy to control within the normal industrial relations framework.
Assessment of measures, legal and physical to fight hijacking
Authors: Tymms Frederick 
Published: July 2022

The object of this paper is to assess the efficacy of various measures, legal and physical, for the prevention of hijacking. I limit myself to examining the inherent limit-ations of different measures; and I propose to elaborate certain proposals, already made, for closing the ring. First, it is desirable to see what conclusions can be drawn from past events.Reports from the airlines on hijacking incidents, during a period of three years from July 1968 to August 1971, have been recorded by IATA. Summaries of these reports have been made available to us, by courtesy of the Director General, through Sir William Hildred. I base my analysis in Tables A to D (see Appendix) on these records, for they are the only source of information available on the course of events and the consequences of each incident.
Another Flying Dragon
Authors: Hart Clive 
Published: July 2022

In my paper “Mediaeval Kites and Windsocks”, I attempted to throw some new light on the curious dragon-shaped objects shown flying on the ends of lines, or fixed to the tops of poles, in a number of mediaeval and Renaissance books of military technology. Until recently these have usually been interpreted as primitive aerostats whose lift is supplemented by wind-forces similar to those which raise a kite.A further illustration of the flying dragon is reproduced here (Fig 1). As it does not belong to any of the general categories or groups into which the other illustrations fall, it is worth considering in detail. Its three-part tail and general outline indicate that it bears some relationship to the dragons depicted in Figs. 6 and 7 of my paper.
Non-linear vibration of rotating cantilever blades treated by the Ritz averaging process
Authors: Rao J. S. , Carnegie W. 
Published: July 2022

The prediction of the forced vibration response of rotating cantilever blading is of considerable importance in the design of turbine and compressor blading where the rotational speeds are relatively high. Non-linearities in the blades arise from the effects of Coriolis accelerations due to the rotation of the blades mounted on the periphery of the disc.Lo and Renbarger derived the differential equations of motion of a cantilever beam mounted on a rotating disc at a given stagger angle and show, for a linear case, that the frequencies of a bar vibrating transversely to a plane inclined at an angle to the plane of rotation can be found by a simple transformation of the frequencies of vibration perpendicular to the plane of rotation. Boyce, Di Prima and Handelman applied the Rayleigh-Ritz and Southwell methods to the case of a turbine blade vibrating perpendicular to the plane of rotation and determined the upper and lower bounds of the natural frequencies.
A Comparison Between Some Approximate and Exact Solutions of the Laminar Boundary-Layer Equations
Authors: Stollery J. L. 
Published: July 2022

There are many approximate methods for solving the laminar boundary-layer equations. They vary greatly in complexity and ingenuity but are similar in that most of them use the momentum integral equation together with data culled from Cohen and Reshotko's valuable catalogue of similarity solutions. Further details may be found, for example, in the book by Curle.Perhaps one of the simplest approximate methods to use is that due to Luxton and Young. More recently Luxton has extended the method so that heat transfer rate distributions also can be obtained. He is careful to point out that, since his method depends on correlations obtained from similar solutions, it cannot be claimed a priori that the method gives an accurate result. Until recently there have been few “exact” calculations against which approximate methods may be tested. Indeed when Morduchow made his review of boundary-layer calculations in 1965 he quoted only two exact results for non-zero Mach number (by NPL) and cast doubt on one of those. Fitzhugh has now computed a number of solutions of the laminar boundary-layer equations using the finite-difference program of Sells. Further solutions have recently been obtained by F. Smith.
Report on the Whittle System of Aircraft Propulsion (Theoretical Stage)—October 1935
Authors: Bramson M. L. 
Published: July 2022

The purpose of this Report is to record the result of an independent step by step check of the theories, calculations and design proposals originated by Fit. Lt. Whittle, and having for their object the achievement of practical stratospheric transport. No investigation of the patent situation has been attempted.The inventions and discoveries of Fit. Lt. Whittle have not yet reached the experimental stage, and so the material available for investigation is, necessarily, confined to a reasoned statement of the principles involved, coupled with justifying aerodynamic and thermodynamic calculations and design proposals.
The Pictures of The Three Favorite Aerial Travellers
Authors: Norton Kings 
Published: July 2022

Early in May 1785, Mr. Vincent Lunardi, famous for the first balloon ascent in England on 15th September 1784, announced that he would ascend again, in his new balloon, on 13th May, this time accompanied by his friend Mr. George Biggin and a lady.For the occasion a stipple engraving (Fig. 1) was published, entitled “V. Lunardi, Esq., Mrs. Sage, G. Biggin Esq.”, showing these individuals in the balloon’s car. On the engraving, the date of publication is given as 13th May, the date fixed for the ascent, Mr. Bovi is named as the publisher, F. Bartolozzi as the engraver and Rigaud as the artist who had painted the picture from which the engraving had been made.
Synthesis of an Aircraft Roll-Stabilisation System: An Application of Inverse Optimal Control Theory
Authors: Porter B. , Woodhead M. A. 
Published: July 2022

During the past decade, the theory of optimal control associated with linear multivariable systems having state and output equations of the respective formsandhas been applied extensively to the design of controllers for a variety of aerospace systems. Such applications of this theory have been mainly concerned with the design of controllers that generate optimal control vectors, ẑ, which minimise performance indices of the form.where Q and R are positive-definite matrices.
Multivariate Search and Its Application to Aircraft Design Optimisation
Authors: Stepniewski W. Z. , Kalmbach C. F. 
Published: July 2022

Long before the legendary Queen Dido cleverly maximised the area of future Carthage by choosing the optimum perimeter shape, man probably consciously or subconsciously tried to optimise his designs as well as his actions.In a more modern time, the post Renaissance period witnessed development of the principles of optimisation on a rigorous mathematical basis, as exemplified in works of Newton, Leibniz, Euler and many others. Eventually, those optimisation ideas were even transplanted by Leibniz and his school to the field of general philosophy, providing an attractive target for the merciless satire of Voltaire in Candide.
Technical Development in Aviation
Authors: Rowe N. E. 
Published: July 2022

It is a signal honour to be invited to give this particular lecture; for me personally, it is especially significant, since for a brief period, 12 months in 1937/38, I held at A&AEE, then based at Martlesham Heath, the equivalent of the post originally held by Tizard in 1916/17, when A&AEE was first formed. At an earlier period, 1926/29, I had been on the staff of A&AEE as a Technical Officer, one of the most enjoyable and fruitful periods of my career. Hence it gives me special pleasure to be here this evening, and a great sense of fulfilment.Sir Henry Tizard was not only a great man, a great man of science, an inspired leader; he was also a great patriot. He spent himself in the service of the country he loved. His anxiety, always, was to see this country forge ahead, to realise her leadership in research and so stride ahead in industry.
The Slug, an Erstwhile Unit of Mass
Authors: Pankhurst R. C. 
Published: July 2022

The general adoption of the International System of Units (SI) in engineering as well as in science makes this the time to relinquish the slug, an engineering unit of mass. Seldom has a convenient unit proved so contentious. This note sets out salient points in the controversy, and indicates basic issues which could scarcely have been appreciated universally at the time.In essence the slug is the unit of mass that goes with the pound force or the pound weight, just as the poundal is the force unit that goes with the pound-mass. There has, however, been a great deal of argument as to whether it is a true derived unit or simply a fundamental unit in disguise, and about how to realise it in practice: in particular, if unit force is defined or established by reference to the gravitational force on the pound-mass, there arises immediately the question of the appropriate value to use for g, i.e. should it toe the local value, the value at a specified place, or some other agreed standard acceleration?
On the Rolling Up of a Trailing Vortex Sheet
Authors: Hancock G. J. 
Published: July 2022

One of the best known results in finite wing theory, which is quoted in aerodynamic text books, states that the distance between two rolled up vortices behind a wing with an elliptic spanwise load distribution is sπ/2, where s is the wing semi-span. Within the framework of linear wing theory this result is correct. But it is of interest to enquire how this result is affected when the standard linear model becomes less valid, for example, at higher wing lift coefficients.In this note, it is assumed that a continuous trailing vortex sheet rolls up into two discrete vortices. These two discrete vortices are assumed to have cores of finite radius; inside the cores the flow is taken to be solid body rotation, while the flow outside the cores is the standard irrotational vortex field. It is assumed that this rolling up process takes place far downstream of the finite wing which generates the trailing vorticity.
Airworthiness and the Air Registration Board
Authors: Tye Walter 
Published: July 2022

To be invited to give the British Commonwealth lecture was an honour which I was proud to accept. As one whose professional life has been concerned mainly with airworthiness of civil aircraft, the choice of the title of the lecture was simple.But I found some difficulty in choosing a theme. The invitation to give this lecture coincided with the issue of the White Paper Civil Aviation Policy. This White Paper placed a large question-mark against the pattern of airworthiness control in future. It seemed to suggest considerable changes to the form in which the Air Registration Board had existed for 33 years, but what the future form would be was obscure.
Space Technology “Spin-off” Benefits to Mankind
Authors: Wiltshire D. A. 
Published: July 2022

With the continuing advances in aerospace technology, the “spin-off” benefits increase, too. Although man has now set foot upon the moon, sent unmanned probes to Mars and Venus and placed a series of satellites into earth orbit, we have only touched upon the fringe of celestial and interplanetary venture. Yet from these early and what will one day seem to be clumsy attempts, we have, as individuals, gained many assets which affect our daily lives.It is indeed regrettable that the enumerable persons who denounce the space-programmes as “a waste of money” “an absolute waste of time”, “unfortunate in that the money could be used to improve the living standards of so many people”, etc., do not give a little more thought to the space programme as a whole, including the “spin-off” benefits.
Future challenges and opportunities in aerodynamics
Authors: Kumar A. , Hefner J. N 
Published: July 2022

AbstractInvestments in aeronautics research and technology have declined substantially over the last decade, in part due to the perception that technologies required in aircraft design are fairly mature and readily available. This perception is being driven by the fact that aircraft configurations, particularly the transport aircraft, have evolved only incrementally over the last several decades. If, however, one considers that the growth in air travel is expected to triple in the next 20 years, it becomes quickly obvious that the evolutionary development of technologies is not going to meet the increased demands for safety, environmental compatibility, capacity, and economic viability. Instead, breakthrough technologies will be required both in traditional disciplines of aerodynamics, propulsion, structures, materials, controls and avionics as well as in the multidisciplinary integration of these technologies into the design of future aerospace vehicles concepts. The paper discusses challenges and opportunities in the field of aerodynamics over the next decade. Future technology advancements in aerodynamics will hinge on our ability to understand, model and control complex, three-dimensional, unsteady viscous flow across the speed range. This understanding is critical for developing innovative flow and noise control technologies and advanced design tools that will revolutionise future aerospace vehicle systems and concepts. Specifically, the paper focuses on advanced vehicle concepts, flow and noise control technologies, and advanced design and analysis tools.
Propulsion airframe integration design, analysis and challenges going into the 21st century
Authors: Early K. 
Published: July 2022

AbstractPropulsion airframe integration design and analysis has many challenges as we move into the 21st century. Along with the conventional challenges of integrating a propulsion system on an aircraft, new technologies and new business drivers dictate innovative approaches to the design process be developed and applied.On the technical side, new innovations in jet noise suppression and new aircraft concepts such as the blended wing body (BWB) will give rise to many challenges in propulsion system performance, operability, and meeting system requirements such as thrust reverse capability. Aircraft engine and aircraft manufacturers must have the appropriate design and analysis tools in place which provide the ability to react quickly to inevitable design changes, driven by constantly changing requirements, during the product development cycle.On the business side, the rapid globalisation of the business dictates that the latest electronic technology be utilised to enable speed in communication with global customers as well as revenue sharing partners. More than ever, cost and schedules dictate the use of analytical methods to minimise the amount of qualification testing. Design and analysis software must be flexible and capable of integrating CAD/CAM and CAE tools while maintaining configuration control of the product.The following paper describes some of the new technical challenges facing the industry. Innovative methods of addressing those challenges are described.