School of Engineering (SoE)

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Open Access
1966 international toy fair Nuremberg 13 - 18 February
(College of Aeronautics, 1966-02) Smith, Charles E.
Nuremberg is a magic city. For one week each February this quaint but bustling place becomes an international wonderland. Not only is a fortune in toy business transacted but a very warm and human thing takes place. Visitors renew old associations and make new ones. Germans, Amercians, Britons, Poles, Belgians, French, Italians, Czechs, Swedes, Danes, Russians, Orientals, and others are involved in the largest display of toys in the world; and with each other, Peoples attitudes toward merchandise become stereotyped after a number of years in the toy business. But their attitudes and behavior toward their one time a year friends take on a new vitality each succeeding year. For American toy buyers the Nuremberg Spielwarenmesse (Toy Fair) offers a convenience of shopping not found elsewhere. The slick, high pressure salesmanship of New York is absent here. It is truly a buyers market. For the American toy manufacturer, Nuremberg affords 4 he opportunity to broaden his market and sources of supply as well as the chance to look for hew items, and even more important, new ideas. The exhibitions are held in five connecting buildings and there is an ample sprinkling of restaurants, snack bars, and vendors purveying the popular Nuremberg bratwurst. These are small sausages served with or without sauer- kraut and mustard. The buildings are well lit and well heated. This year these pleasant physical conditions were supplemented by unseasonably warm, clear weather.
Open Access
2-port as an anlalogue of the Lorentz transformation of special relativity theory
(College of Aeronautics, 1961-04) Deards, S. R.
If the variables associated with a linear resistance 2-port are identified with the variables of special relativity theory, it is shown that a resistance 2-port transforms its port variables according to the Lorentz equations.
Open Access
Ablation studies of low melting point bodies in a pre-heated supersonic air stream
(College of Aeronautics, 1960-02) Cleaver, J. W.
This report is an investigation into the melting of axi-symmetric and two-dimensional bogies at a Mach No. of M[infinity] = 1.78 and stagnation temperatures up to 550 [degrees]K. In this temperature range, the most suitable material for the models was found to be an eutectic tin-lead alloy a melting point of 456 [degrees]K. For the cone and hemisphere-cone models two distinct modes of melting were observed. In cases where the estimated equilibrium surface temperature (Tw)o was approximately equal to the material melting temperature Tm, melting occurred only at the stagnation point of the model and was such that a flat surface normal to the gas stream always resulted. If the average rate of heat transfer at the air-liquid interface be defined as qi = LmPm x, where Lm is the latent heat of fusion, Pm is the density of the material and x is the rate of recession of the flat surface, it is found that qi decreases with increase of the radius of the flat nose. A very approximate theory is found to show some agreement with the experimental rates of heat transfer. When (Tw)o was considerably greater than Tm the flat surface was no longer preserved and the resulting steady ablating shape was paraboloidal in nature. When this occurred x was usually constant. This allowed some average steady state heat transfer rates to be evaluated and compared with theory. Preliminary tests were also made with a two-dimensional wedge model.
Open Access
An abstract of a paper by D. Battat 'a new kinetic approach to the shock wave structure'
(College of Aeronautics, 1966)
Open Access
The acquisition of high speed skills. First progress report on D.S.I.R. research project
(College of Aeronautics, 1963-04) Whitfield, D.
N/A
Open Access
Addendum to type record. Avro "Lancaster" Mk.1 P. A. 474 Type record No. 1/P1/Lancaster. Investigation of boundary layer conditions on wings. M.O.S. Contract No.6/Aircraft/9807/C. B. 6(a)
(College of Aeronautics, 1956-01) College of Aeronautics, Department of Aircraft Design
Introduction The investigation involves, briefly, the mounting of a wing of 45' sweep-back in a dorsal position on the fuselage of 'Lancaster' P.A.474 such that wing incidence will be variable in flight over a 20 range, i.e. ± 100. A ‘partial chord’ technique for swept wings has been established by the College using a similar wing mounting configuration on an Avro 'Anson' Aircraft and this technique has been applied to the current investigation.
Open Access
An advanced course in air transport engineering
(College of Aeronautics, 1966-08) Hyde, David
In 1963 K.G. Wilkinson, then Assistant Chief Engineer of British European Airways, emphasised the lack of formal engineering education in the maintenance and operation of aircraft. This report describes the nine-month postgraduate-level course in Air Transport Engineering which was started in October, 1964 at The College of Aeronautics, Cranfield, in order to help in satisfying this requirement.
Open Access
The aerodynamic characteristics of a family of related hovercraft shapes
(College of Aeronautics, 1967-09) Andrews, E. J.
The handling qualities of hovercraft indicate the need for a better understanding of the influence of the basic aerodynamic characteristics. This report is the first of a series in which the aerodynamic characteristics of hovercraft shapes are studied with particular reference to current design variables starting with simple solid block models and progressing to more sophisticated hollow models having cushion efflux and air-induction.
Open Access
Aerodynamic characteristics of a hypersonic parachute
(College of Aeronautics, 1961-11) Boyd, E. A.
Newtonian theory, both in the form of the Modified-Newtonian and the Newton- Busemann pressure laws, is used to find the shape, cloth area and drag of the axisymmetric canopy of a hypersonic parachute, whose only load-carrying fibres are longitudinal ones. As an example, an estimate is made of the size of canopy needed to give a drag of 20,000 lb. in flight at a Mach number of 10 at 100,000 feet altitude.
Open Access
The aerodynamic characteristics of the jet wing and its application to high speed aircraft
(College of Aeronautics, 1961) Alexander, A. J.
The slender wings and bodies suitable for supersonic flight have, in general, relatively poor aerodynamic characteristics especially at lay speeds. In order to improve their performance the use of edge blowing has been explored. In this scheme high velocity air jets in the form of thin sheets are used to fix separation lines on the wing or body and to favourably influence the external stream. Thus the equivalent wing, called here the "Jet Wing” is composed of the wing-body itself plus the extended curved jet sheets which spring from its edges. A limited use of edge jets has been proposed in the 'Jet Flap' concept but the efficiency of this device fails off with decreasing aspect-ratio and the problem of trimming could be severe as most of the increased lift is generated near the trailing edge. At very law aspect-ratios a considerable part of the lift is contributed by the leading-edge vortices which dominate the flow field at moderate incidence. It follows therefore that leading edge blowing is particularly useful for small aspect-ratio wings and the trimming problem can be avoided by a suitable jet arrangement which does not disturb the conical nature of the flow. When sufficiently large auxiliary thrusts are available peripheral jet sheets can be deflected downwards close to the ground, the air craft becoming a Ground-Effect-Machine, with substantial reductions in both take-off and landing speeds and distances.
Open Access
Aerodynamic characteristics of two low aspect ratio rectangular wings at Mach 2
(College of Aeronautics, 1956-04) Marson, G. B.
This note summarises the important results of a detailed experimental investigation into the flow and pressure distribution over two rectangular single wedge wings. The experiments were carried out .in the 9" x 9" supersonic tunnel at the College of Aeronautics, 6 at a Mach number of 2.0 and a Reynolds number of 2.5 x 10 per foot. Both wings had a chord of 3 inches and a total wedge angle of 6°. They had no real trailing edge, but were faired into a cylindrical support which could be rolled and pitched in the tunnel. Wing A was of 2 inch1span, giving an aspect ratio of 0.67. `Ting B was of 1 1/4 inch span, 0.42 aspect ratio. 132 pressure tappings 4 were spaced regularly over half of one surface of each wing, and up to 19 pressure readings could be taken simultaneously on vertical mercury manometers. models were pressure plotted at pitch angles of 0°, 2 1/2°, 5°, 7 1/2°, 10°, 15°, 20°, 25°, and 30°, and at all roll angles at intervals of 30°. Since each wing was symmetrical about the centreline, the complete pressure distribution over all surfaces at any roll angle Ø could he obtained from the readings taken on the one surface at Ø, 180°- Ø, 180° + Ø, and 360°- Ø. The pressure readings were then integrated to give the forces and moments on the complete wing… [cont.].
Open Access
The aerodynamic derivatives of an aerofoil oscillating in an infinite staggered cascade
(College of Aeronautics, 1960-01) Craven, A. H.
Thin aerofoil theory is used to obtain, in integral form the aerodynamic derivatives of an aerofoil oscillating in an infinite cascade. The theory allows for arbitrary stagger angle and phase difference between adjacent blades of the cascade. The expressions obtained reduce, for zero stagger and for in phase and antiphase oscillations, to known results.
Open Access
The aerodynamic derivatives with respect to sideslip for a delta wing with small dihedral at supersonic speeds
(College of Aeronautics, 1947-12) Robinson, A.; Hunter-Tod, J. H.
Expressions are derived for the sideslip derivatives on the assumptions of the linearised theory of flow for a delta wing with small dihedral flying at supersonic speeds. A discussion is included in the appendix on the relation between two methods that have been evolved for the treatment of aerodynamic force problems of the delta wing lying within its apex Mach cone. Continues…
Open Access
Aeroplane design studies conventional and V.T.O.L. freighter aircraft (Academic Years 1959 and 1961)
(College of Aeronautics, 1963-11) Howe, D.
During the second year of their course in the Department of Aircraft Design, students have the option of working as a member of a team engaged in a design study. The subjects for the studies are chosen to represent the current interests of the industry and include unusual features considered to be worthy of investigation. Examples of these design studies are the F-59 freighter and its derivative the F-61, V. T.O. L. freighter. In a conventional role these designs are intended to carry a payload of up to 77000 lb. , over 800 nautical miles range, using four turboprop engines. V. T.O. L. capability is given to the F-61 design by the addition of two wing pods, each of which houses 22 lift engines. The application of boundary layer control in the form of blown ailerons and flaps has been investigated for the F-59 design. Both aircraft have been designed in detail. The major conclusion of the studies is that the application of V. T.O. L. to large freight aircraft is feasible, but further detailed work is necessary to resolve some flutter and noise problems.
Open Access
Aeroplane design studies mach 2.2 and mach 3.0 supersonic airliners (academic years 1960 and 1962)
(College of Aeronautics, 1965-02) Howe, D.
This report is divided into three parts. The first two of these describe the A-60, Mach 2.2 airliner and the A-62, Mach 3.0 airliner design studies respectively. Apart from the different cruise speeds these two aircraft were designed to meet the same basic requirements and the third part of the report is a comparison of them. The Mach 2.2 design was based upon the use of a slender, integrated, delta layout with six turbojet engines buried in the rear fuselage. It was intended to carry up to 120 passengers over transatlantic ranges. Although the chosen engine installation enabled a compact aircraft to be designed it did introduce severe structural and installation difficulties. A canard delta arrangement was proposed for the Mach 3.0 aircraft. Drooping of the wing tips for supersonic flight was found to confer important stability advantages without introducing an unacceptable weight penalty. The steel structure was designed around the use of both corrugated reinforced and honeycomb sandwich skins, the former being preferable. An interesting feature was the choice of a sealed, cryogenic, environmental control system. This was found to be very attractive but as it proved to be somewhat heavier than anticipated it is suggested that a good compromise could be obtained by using a more conventional system for subsonic flight phases. The major conclusion from the comparison between the two study aircraft was that in many respects there is very little to choose between them. However the Mach 2.2 aircraft represents a more logical step from existing airliner designs and presents fewer materials problems. As it is comparable economically it represents a better choice for a first generation supersonic design.
Open Access
Aeroplane design studies: bpropeller turbine and pure jet powered general purpose transport aircraft (academic years 1963 and 1965)
(College of Aeronautics, 1967-05) Howe, D.
The recent interest in the air bus conception of air travel is reflected in the aircraft chosen for study by the students in the Department of Aircraft Design during the 1963 and 1965 academic years. The first study was based upon the use of four propeller turbine engines to power an aircraft capable of carrying up to 40,000 lb. of payload over short stage lengths. Emphasis was placed on the need for operations with mixed passenger and freight loads and the fuselage layout incorporates two decks, the lower one of which is designed as a freighthold with nose loading doors. The second study was similar except that four wing mounted pure jet engines replaced the propeller turbines of the earlier design. The cruising speed is thus some 50 per cent higher with a Mach number limitation of 0.8. The two deck fuselage layout is retained, but with a rear loading door for the freighthold, and the wing has 28° of leading edge sweepback . An initial economic comparison of the two aircraft revealed that when the aircraft are operated over 250 n. mile stage lengths the direct operating costs of the propeller turbine powered design are some 20 per cent less than those of the pure jet version. This is mainly due to the much lower first cost of the simpler aircraft.
Open Access
Aircraft design studies: variable sweepback naval aircraft
(College of Aeronautics, 1967) Howe, D.
A preliminary survey of the possible applications of variable sweepback indicated that a substantial improvement in performance can be expected when the concept is applied to a naval strike aircraft. In order to assess this performance gain and to obtain experience of the engineering problems involved, the subject of the design study 'ay the students in the Department of Aircraft Design during the 1964 academic year was chosen to be a variable sweepback naval strike aircraft. The aircraft has a maximum take off weight of 60, 000 lb. and a limiting Mach number at altitude of 2. 5. Various payloads up to a maximum of 4000 lb. can be carried externally over ranges which vary up to 4000 n. miles according to the role. Alternative mechanical arrangements for the wing hinge system were investigated.
Open Access
American teaching and practice of industrial engineering and management
(College of Aeronautics, 1956-02) Cherry, J.
In June 1954 a small mission, comprising T.B.Worth, A.M.I.E.E., M.I.Prod.E., F.R.S.A., Principal Senior Lecturer in Production Engineering and Assistant Head of the Department of Mechanical and Production Engineering at Birmingham College of Technology, K.J.Shone, M.A. (Cantab),A.M.I.Mech.E., M.I.Ear.E., M.E.I.C., Head of Department of Industrial Administration, Royal Technical College, Glasgow, and the author, visited the United States of America to "observe and gain experience of American methods of training in Industrial Engineering and Management both in universities and industrial plants". Subsequently, in September, D.M,Williams, Ph.D., B.Sc., (H.M.I.) joined the mission, which returned in November 1954. Each member investigated different aspects and separate reports are being presented. This report deals mainly with education in Industrial Engineering. Other Sections, dealing with education in Management, Industrial Engineering and Management in Industry, Research and Consultancy will be presented subsequently by the author. Education in Industrial Engineering in the U.S.A. laid emphasis on the need for sound education in the bagic and engineering sciences prior to the study of Industrial Engineering subjects. Considerable attention was paid to the economic aspects of industry and subjects such as Engineering Economic Analysis were prominent. Awareness of the impact of new developments in the industrial engineering field was also evident and curricula were being revised to introduce subjects such as Electronic Theory into the electrical programme, and the application of Operations Research techniques'to the mathematics programme. The value of formal education in Industrial Engineering was acknowledged by most industrialists, who were absorbing I.E. graduates at a rate exceeding 1500 per annum.- In 1954 there were approximately 8,000 students enrolled in. I.E. courses. A comparison of equivalent courses in Great Britain showed that less than 50 students were enrolled. The comparison also revealed the inadequacy of the Higher National Certificate courses in Production Engineering, and a strong plea is made for more facilities for students to take Higher National Diploma courses in Production Engineering.
Open Access
An analogue method for the analysis of current carrying semiconductor systems
(College of Aeronautics, 1963-09) Loeb, H. W.
In an earlier Internal Technical Memorandum (1) and in subsequent work(2), it has been demonstrated that a particular kind of resistance network, in which non-linear elements are associated with each mesh point, can be made to represent an exact analogue to a non-degenerate semiconductor system in the equilibrium or quasi-equilibrium state. The term !exact' in this context implies that the difference equation which governs the potential distribution in the network becomes identical, for the limit of vanishing mesh interval, with the differential equation for the electrostatic potential within the semiconductor system, i.e. the Shockley-Poisson equation. From this type of analogue network information concerning the variation of maximum field intensity and of junction capacitance with applied bias voltages can be obtained for one, two and three dimensional configurations of p and n type regions of arbitrary geometry and impurity concentration profiles. One limitation to the applicability of the analogue technique arises from the restriction to quasi-equilibrium conditions. This restriction precludes the investigation of situations in which current flow contributions to the carrier concentration pattern become significant - for example, in the case of strongly forward biassed p-n junctions, and of p-i-n junctions and transistors operating at high injection levels. In the present paper, the problems involved in an extension of the basic analogue method to the treatment of non-equilibrium situations are examined, and means for their solution are discussed. A review of the methods previously described and an illustration of the nature of their limitations is given in Section 2. This is followed, in Sections 3 to 7, by a detailed treatment of the case of a current carrying semiconductor system in one dimension which leads to a theoretically possible realization in terms of resistancenetwork/ analogue computer techniques, which is, however, too complex to. be considered practical. Section 8 discusses means for the simplification of the proposed schemes and leads to the description of a relatively simple system in which a significant reduction in equipment complexity has been made possible by the adoption of an operating mode based upon an iterative process of successive approximations. The extension of the technique to three dimensions is outlined in Section 9.
Open Access
An analysis of an unstiffened cylindrical shell subjected to internal pressure and axial loading
(College of Aeronautics, 1961-03) Houghton, D. S.; Johns, D. J.
General equations are obtained for the deflections and stresses in long thin unreinforced cylinders, which are subjected to an axial load and internal pressure. By making suitable simplifying assumptions, results are presented which show the variation of the structural weight parameter with the structural axial loading index, for both pressurised and unpressurised shells. An allowance is made for the effects of shell initial eccentricities on the buckling stress coefficient K, in accordance with R. Ae.S. data sheet 04.01.01. Extreme cases are considered, in which the shell is assumed to be either fully effective (K = 0.6). 0:. completely ineffective (K = 0), in resisting axial compressive loads. For this latter case, complete pressure stabilisation of the shell is considered, and it is shown that the weight penalty involved in using this design philosophy, is negligible for a certain range of the structural loading index. A simple modification to the analysis for this case, i.e. K = 0, is made to allow for the effect of an external longitudinal bending moment.