bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seaplane research — the MAEE contribution
Authors: Hamilton Sir James , Allen J. E. 
Published: July 2022

AbstractSeaplanes were an important feature of aviation during its first four decades, both for long range transport and high airspeeds. Research, and the testing of new designs, was carried out at the Marine Aircraft Experimental Establishment at Felixstowe until 1958. However, the record of this scientific work at MAEE has never been fully reported until this paper. The main scientific topics described are, stability during take-off and landing, hydrodynamic resistance, landing impact, spray formation and its control. Armament research and testing receive special attention. A large fleet of prototype seaplanes was type tested; results from these type tests are summarised to show the wide range of designs needing to be assessed. In a final section the authors consider how seaplanes may return to the main stream in the 21st century.The two authors were respectively Head of the Scientific and Technical offices at MAEE in the 1940s.
Study of unsteady characteristics of flare-induced hypersonic shock-wave boundary-layer interaction flowfield with variation in γ
Authors: Verma S. B. 
Published: July 2022

AbstractExperimental work has been carried out to study the unsteady flow-field characteristics related to shock-wave/boundary-layer interaction. Tests were carried out on an axisymmetric configuration that has a semi-cone angle of 35° and a flare angle of 20°. Further influence of low γ gases (C02 and CF4) on the overall interaction process is also investigated. Both surface and off-surface analysis has been carried out. Off-surface study has been made with a laser schlieren system. The purpose of this study was to investigate the source of the unsteadiness related to such interactions. Two types of shock motions, namely, flapping and rippling could be identified for air, the relative importance of each of which is strongly dependent on the location within the interaction and on the type of test gas. Spectral analysis shows the large-scale motion of the separation bubble to be the main source of high amplitude fluctuations. However, the existence of separation bubble itself does not necessarily indicate the prevalence of unsteady flow conditions.
Biologically inspired visual sensing and flight Control
Authors: Barrows G. L. , Chahl J. S. , Srinivasan M. V. 
Published: July 2022

AbstractThere is increased interest in new classes of mini- and micro-UAVs with sizes ranging from one metre to ten centimetres. Many envisioned applications of such UAVs require them to be able to fly close to the ground in complex environments. The difficulties associated with flying in such environments coupled with the reduced payload capacity of such airframes means that new methods of sensing and control need to be considered. Good models for such methods are found in the world of flying insects. One particular visual cue used by insects is optic flow, which is the apparent visual motion seen by the insect as a result of its motion through the environment. This paper discusses several research efforts aimed at developing new sensing and control algorithms inspired by insect vision and flight behaviors. These efforts are part of DARPA's controlled biological and biomimetic systems (CBBS) programme. In these (and related) efforts, many elegant control stratagems have been discovered which suggest that simple reflexive schemes combined with the measurement of optic flow may be sufficient to provide many aspects of autonomous navigation in complex environments. Furthermore, these efforts are implementing these behaviors in real flying UAV platforms by using novel hardware and software to measure optic flow, and inserting optic flow measurements into a control loop using a combination of ‘best engineering approaches’ with inspiration taken from biology. This has resulted in fixed and rotary-wing mini-UAVs that are able to hold an altitude and perform terrain following.
Turbulent mixing layer from two non-parallel streams
Authors: Azim M. A. , Islam A. K. M. S. 
Published: July 2022

AbstractAn experimental investigation has been conducted on the mixing layers produced from the merging of two non-parallel streams. To study the effect of velocity ratio on its development, mixing layers were produced with velocity ratios 0·7, 0·8 and 0·9. The boundary layers were untripped and initially turbulent in all the cases. For each velocity ratio, measurements were made at six streamwise locations. It was found that for velocity ratios 0·7 and 0·8, mixing layers appear to attain self-similarity but failed for 0·9 within the measurement domain. The development distance of the mixing layer flow was increased with increasing velocity ratio and the splitter wake was found to play an important role in its development. The mixing layer growth was found to decrease with increasing velocity ratio though the spread of the layer was larger at the high speed side.
Progress in the development of a versatile pilot model for the evaluation of rotorcraft performance, control strategy and pilot workload
Authors: Bradley R. , Brindley G. 
Published: July 2022

AbstractThe evaluation of rotorcraft performance and handling qualities in piloted flight using a desk-top simulation is a desirable facility. The development of the SYCOS pilot model has brought this capability closer by simulating piloted flight along prescribed trajectories such as the Mission Task Elements of ADS-33. This development has overcome some of the limitations of the precise control of inverse simulation, by adopting a structure which includes a corrective component that adjusts the control strategy to counteract departures from the desired flight path. The development and implementation of SYCOS for a range of rotorcraft types and applications is shown to be well defined and straightforward. The capability and reliability of SYCOS is demonstrated through a number of recent applications in performance, control strategy and pilot workload studies. Some of the applications benefit from enhancements to the basic structure and these are described in context. The accumulation of experience with the SYCOS pilot indicates that it is a significant advance as a predictor of human control activity during helicopter manoeuvring flight.
Aerospace applications of luminescent paint
Authors: Kingsley-Rowe J. R. , Lock G. D. , Davies A. G. 
Published: July 2022

AbstractA heat transfer measurement technique has been developed, which utilised a laser to heat a spot of the ‘standard’ luminescent paint on an insulated metal wind tunnel model. The convective heat transfer coefficient was determined from the experimental quasi steady-state surface temperature, and solutions obtained from radial and axial conduction in a numerical heat transfer model. The convective heat transfer coefficient variation over both a flat plate and a NACA 0012 aerofoil have been measured in transonic flow. Measurements obtained from the flat plate were seen to agree well with correlation data from the literature. Measurements on the NACA 0012 aerofoil indicated the point of transition from laminar to turbulent boundary layer as well as the location of shock boundary layer interaction. The luminescent paint provided simultaneous measurements of pressure and temperature (see Part 1). The distribution of pressure over the NACA 0012 aerofoil was shown to be in excellent agreement with conventional transducer data, although the luminescent paint data provided greater spatial resolution. The position of the shock determined from the heat transfer measurements was shown to be in excellent agreement with the pressure measurements.
Civil aviation and the environmental challenge
Authors: Green J. E. 
Published: July 2022

AbstractIn the coming century, the impact of air travel on the environment will become an increasingly powerful influence on aircraft design. Unless the impact per passenger kilometre can be reduced substantially relative to today’s levels, environmental factors will increasingly limit the expansion of air travel and the social benefit that it brings. This essay considers the three main impacts, noise, air pollution around airports and influence on climate change. Of the three, impact on climate change is taken to have the greatest long-term importance and is discussed at the greatest length. It is argued that, of the three main contributors to climate change from aircraft – CO2emissions, NOXemissions and the creation of persistent contrails – it is the last two which are the most promising targets. Ways of reducing the impacts of these two are discussed and it is noted that, in each case, the best environmental result is likely to entail some increase in CO2emissions. It follows that regulatory or economic measures to reduce impact on climate should be framed so as to do just that. Measures framed purely in terms of CO2emissions are likely to be counter-productive. Nevertheless, the design of aircraft to reduce fuel burn and hence CO2emission remains a key long-term objective; the essay considers the potential offered by new technology and new design concepts in this arena.
Passive mm-wave imaging from UAVs using aperture synthesis
Authors: Harvey A. R. , Appleby R. 
Published: July 2022

AbstractPassive imaging using mm-waves offers very significant advantages in scientific and military surveillance. However, the relatively long wavelengths mean that for the resolutions that are typically sought, the input aperture of the imager needs to be quite large; typically in excess of one metre. Deployment of conventional dish antennae of these dimensions on small aircraft is highly problematic. The use of snapshot synthetic aperture interferometric radiometry (SAIR) offers an attractive route to integrating a two-dimensional antenna array into the structure of an aircraft so that the transverse effective dimensions of the antenna can be almost as large as the aircraft. We report here a study into the feasibility of deployment of a SAIR on unmanned airborne vehicles and the achievable performance parameters. Critical considerations are the achievement of acceptable sensitivity and angular resolution from a SAIR that does not require excessive complexity. It is shown that traditional approaches based on fully sampling the spatial frequencies in the scene are unable to simultaneously meet all of these criteria, but that a SAIR based on thinned sampling of the spatial frequencies shows promise.
Future air traffic management: strategy and control philosophy
Authors: Brooker P. 
Published: July 2022

AbstractThe aim is to explore the philosophy of air traffic management with different strategic visions of the future: to answer the key question: ‘Who is to prevent mid-air collisions and how are they to accomplish this?’ The best strategic vision may just be the one that has the best match with the consensus on the desired strategic direction. Nevertheless, it must satisfy the main safety, financial, human performance etc. constraints. To explore the question, a blend of concepts from a range of disciplines has been used. These include risk analysis, financial decision-making, ‘cognitive engineering’ research and simple cybernetics. ‘full delegation’ – with pilots being responsible for all the tasks related to separation assurance – appears to meet most of the constraints. Some important issues for safety analyses of full delegation are sketched. Research into the nature and rate of future conflicts in a full delegation environment, using models of error processes, is crucial.
Flight simulation – viability versus liability issues of accuracy, data and validation
Authors: Rolfe J. M. , Hampson B. P. 
Published: July 2022

AbstractFlight simulation has become an indispensable tool for aviation training. Important decisions relating to the acquisition and certification of aircrew proficiency are made based on performance in simulated flight conditions. Such a high dependency on simulation can invite questions about the validity of the assumptions on which their employment is founded. If these should be shown to be in any way deficient, those who consider that they have suffered as a result may seek redress. The paper considers the possibility that such conditions could arise and require those involved in the design, manufacture, regulation and operation of flight simulators to justify their decisions. The paper suggests that the culture should be one which acknowledges that simulation has its limitations and, consequently, exercises a duty of care for those who undertake training and assessment in flight simulators.
Elastic buckling design curves for isotropic rectangular plates with continuity or elastic edge restraint against rotation
Authors: York C. B. 
Published: July 2022

AbstractElastic buckling design curves are presented for flat isotropic rectangular plates, which are either isolated or form part of a larger continuous plate structure. The design curves illustrate the effect of introducing combinations of elastic rptational restraints to the edges of simply supported isolated plates, which are subject to uniform in-plane compression or shear. Results for infinitely long and/or wide plates, with rectangular bays, are superimposed for comparison.
50 years of turbomachinery research at Pyestock — part 2: turbines
Authors: Dunham J. 
Published: July 2022

AbstractThe two parts of this paper summarise the turbomachinery research undertaken at Pyestock during the 50 years since the National Gas Turbine Establishment was formed in 1946. The theoretical and experimental activities are described, and their influence on UK military and civil aero engines is assessed. The way in which NGTE supported non-aeronautical gas turbines is also explained. Part 2 covers turbines.
Civil helicopter operations with British Airways
Authors: Parker M. A. 
Published: July 2022

My experience qualifies me only to discuss maintenance aspects of our operation, and I feel very strongly that we in British Airways Helicopters have been forced into developing major design modifications in the past and that insufficient time and experience has been left over to devote to improving our maintenance philosophies and systems.This was inevitable in the early days, but I now wish to make our position perfectly clear. We, in engineering, are predominantly in the maintenance business and our development and research time will become more and more biased towards maintenance problems.
The economics and noise of subsonic aircraft
Authors: Brown D. G. , Lawson K. S. 
Published: July 2022

Noise and economics are major interlinking factors which are likely to have an impact on the whole future pattern of civil air transport development. In the past decade environmental pressures increased the need to design for low community noise levels; however, the fuel crisis and inflation have now shifted emphasis back towards fuel economy and lower operating costs.The rate of growth achieved by air transport during the past three decades far exceeds that of any other transport system; this considerable rate of growth is clearly illustrated by, for example, the overall increase in total annual passenger movements at London's Heathrow airport, as shown in Fig. 1. It will be further noted that, despite the tendency for aircraft size to increase, the total annual aircraft movements at the same airport also show an overall growth pattern.
An attitude control system for a flexible satellite providing active damping of flexural motion
Authors: Gething J. M. , Gill K. F. 
Published: July 2022

A great deal of interest has been shown in recent years in the problem of flexibility in spacecraft structures. Much published work has been devoted to analysing the dynamic interaction between deformation of flexible appendages and attitude control systems. A limited number of publications have sought to find ways of providing some form of active control of flexible motion. Where this has been attempted idealised systems consisting of flexible coupled pendulums or rotors have been considered.The problem of flexibility may be tackled in three ways. Where the flexure can be shown to be secondary in nature, careful design of the attitude control system can ensure that interaction is kept to a minimum. To this end surveys of structural flexibility effect in spacecraft are invaluable to the design engineers. Where the flexural motion has a more dominant effect, as will follow from the inevitable increase in power requirements for communications, then a more direct approach will become necessary.
Design for safety
Authors: Tye W. 
Published: July 2022

Since the advent of air transport half a century ago, safety has been a dominating influence in aeroplane design. It is by no means the only factor. The successful designer is one who uses his talents to arrive at the best balance between the competing demands of speed, reliability, comfort, and cost, while satisfying the demands of safety.The fundamental reason why the aeroplane places high demands on the designer, perhaps to a greater degree than is the case with surface vehicles, is that the aeroplane proceeds on its way in defiance of gravity. It has to be light enough to fly, and it cannot stop for running repairs. Working within the limitations of available materials and fuels, it took mankind a long time to discover how to make an aeroplane light enough to fly at all. It is a near miracle that some 70 years later, today's aircraft carry large loads for long distances with remarkable safety.
Operations
Authors: Owens Charles 
Published: July 2022

This paper deals with two operational aspects of civil aircraft design of major interest to Operators and Pilots,
(i)Flight Control Systems and(ii)Information Requirements.The first of these describes the problems encountered in our 10 years experience of autoflight, and the operational requirements arising from this, while the second describes the problems caused by the limitations in the availability and display of information to the pilot, and proposes improvements in three areas.
Ground organisation of aerial crop spraying
Authors: Perrow Peter M. G. 
Published: July 2022

Although the aeroplane itself is the king pin of aerial spraying, without the staff to sell the proposition and the ground personnel to organise and service it, the aeroplane could not operate efficiently and economically.Aerial spraying is undoubtedly the most dramatic operation which contractors undertake on farms in the United Kingdom. It is the one about which the general public are most aware because in the first place they are affected more by this operation in areas near farms than by other contract operations; and second if there is any untoward incident with an aeroplane they hear about it on television and read about it in the newspapers. If a contractor has an accident with a sugar beet harvester or a combine it is hardly newsworthy.
Co-operation between the parties to the project itself and third parties
Authors: White C. B. 
Published: July 2022

Mr. Jenkins has described to you the matters between the collaborating parties. My task is to describe the problems between them and outsiders.Because hardly any major European aerospace project lacks some form of collaboration, perhaps I may just make a few points from my own experience of this sort of business.International collaboration has daunted many people, for rather the same reason that a lawyer like myself feels incapable of imagining how the process of a design office can ever achieve anything!A lot of what occurs in the design office is summed up in the phrase “know-how”—I have often thought that there is no less a “know-how of collaboration”, particularly international collaboration.
Some experiments on the flow past a sphere
Authors: Calvert J. R. 
Published: July 2022

There is little published work on the flow past a sphere. Some experiments were carried out in the 1930s (see Fage), and other measurements have been made more recently (Cometta and Kendall). Much of the work has been restricted to flow visualisation and to measurements of drag and surface pressure distribution. Very few measurements have been made in the near wake.In the present paper, measurements of vortex shedding frequency, wake dimensions and static pressure up to three diameters downstream are reported. The experiments were carried out in the Aerodynamics Laboratory of the Cambridge University Engineering Department, under the supervision of Professor W. A. Mair.
An airports system for United Kingdom air services
Authors: Masefield Peter 
Published: July 2022

Forty years ago Flight Lieutenant John Nelson Boothman, AFC, RAF, won the Schneider Trophy outright for the Royal Aero Club of the United Kingdom, flying a Vickers-Supermarine S-6B (S.I595) on Sunday 13th September 1931. “The better the day the better the deed.”To some, that win at 340.8 mph over a 270 mile course seemed the end of an era and the climax of the careers of both Reginald Mitchell, and of Henry Royce, the designers of the S-6B and of its 2300 bhp Rolls-Royce “R” engine.In the event, as history has unfolded, the winning of the Schneider Trophy was but the opening page of a more significant story—the evolution of Mitchell's Spitfire, of Camm's Hurricane and of their Rolls-Royce Merlin engines. Those later Schneider Contests—from 1927 to 1931—led directly to the winning of the Battle of Britain in 1940—and to our presence here in a free world tonight.
Industrial relations in civil air transport
Authors: Thomas Tudor 
Published: July 2022

Under the Civil Aviation Act there is a responsibility on the Airways Corporations to establish machinery for the determination of terms and conditions of employment and consultation with the staff they employ. There is, equally, a responsibility upon the Boards of the Corporations to recognise those unions who are appropriate to the grades of staff they employ.The machinery, which was created in 1949, was based on the concept of Whitleyism but its application had to be rather wider than was the case in other industries because:(i) Civil aviation was in its infancy at the time(ii) The formidable task of bringing together a wide variety of skills(iii) The problems of adjusting to the varying practices and philosophies of unions catering for a wide variety of occupational groups.
Pitcher and the Multiplane; an addendum to the paper published in the May issue of The Aeronautical Journal
Authors: Jarrett Philip 
Published: July 2022

Following the publication of my paper “Pilcher and the Multiplane” in the May issue of the Aeronautical Journal, I have had cause to reperuse the various accounts dealing with the operation of the “gust damping” device used by Chanute on his quadruplane and probably adopted by Pilcher for the multiplane.Referring back to the original patents, which I had read thoroughly during the preparation of the paper, I realised that I had omitted to mention Chanute’s proposal of the deliberate operation of this system as a positive means of control.
The operational angle
Authors: Newham D. F. 
Published: July 2022

The purpose of this paper is to outline the “operational angle” of the hijacking problem and of the measures which might be taken to combat it.Before considering what can be done on the aircraft itself to prevent or deter the hijacker from achieving his or her objective, I think it important to first review the likely circumstances of a hijack incident. By this I hope to ensure that my conclusions are seen against an essentially practical background.