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ON Friday, March 24, 1961, the Minister of Aviation, Mr Peter Thorneyeroft, officially opened a new high supersonic speed wind tunnel at the Royal Aircraft Establishment, Bedford. This tunnel provides the final stage in the present plans for expansion of the wind tunnel facilities at Bedford, being capable of providing speeds from Mach 2.5 up to Mach 5 in a working section measuring 4x3 ft. Three other tunnels arc already in operation at Bedford—these being the 13x9 ft. working section low‐speed tunnel, the 3x3 ft. tunnel, which is transonic and supersonic to Mach 2, and the 8x8 ft. tunnel, which is subsonic and supersonic to Mach 2.8.

DURING the first forty years or so of the history of manned flight, the application of aerodynamics was confined largely to subsonic speeds and to one basic aircraft shape. Since the end of the Second World War the aerodynamic domain has expanded in spectacular fashion in terms of speed and shape until at the present time ‘conventional’ manned aircraft are penetrating into the realms of hypersonic velocities and the satellite vehicle has brought with it aerodynamic problems at what must surely be the near‐ultimate speed range for the technology. Nor are these advances confined to high‐speed aerodynamics: they include radically new approaches to low‐speed problems, particularly those arising from take‐off and landing manoeuvres.

Originally, this article took the form of the Twenty‐first Brancker Memorial Lecture delivered to a meeting of The Institute of Transport. The author began his lecture by saying how honoured he was by the invitation to present the 1964 Brancker Memorial Lecture and that he felt especially privileged to have the opportunity of surveying a prospect which he believed would have excited Sir Sefton Brancker's most ardent enthusiasm—the prospect of reducing inter‐continental journey times‐by air to the same durations as those universally accepted for inter‐city journeys by rail and road. Previous Brancker Memorial Lectures had summarized the general development of British civil aviation from its earliest days to 1946 and had covered particular aspects of its very rapid expansion since that date. 1946 was a significant year because it marked the resurgence of commercial flying after seven years of wartime restrictions and regulation; it promised a new deal to both operators and travelling public, with the opportunity of usefully applying technical advances achieved during the war period; at the same time it threw into sharp contrast the relative design capabilities of the British and American aircraft manufacturing industries.

Part I—The Jet Propulsion Engine IN a study of high‐speed flight presented to the Accademia dei Lincei in 1926 (G. A. Crocco, The Possibilities of Super‐Aviation, February 7th, 1926) an outline was given of the problem of ‘super‐aviation’, i.e. flight in excess of the speed of sound and made economical by operating in the stratosphere. Then in 1931 (G. A. Crocco, Aerodynamic Bodies of Negative Resistance, Rendiconti Lincei, June 12th, 1931), a jet‐reaction engine in which the external air was entrapped was described as representing a possible solution of this problem; the principle was indicated diagrammatically as long ago as 1931 by Lorin.

This study aims to decrease the aerodynamic drag of the body of revolution at supersonic speeds. Supersonic area rule is widely used in modern supersonic aircraft design. Further reduction of the aerodynamic drag is possible in the framework of Euler and Reynolds averaged Navier–Stokes (RANS) equations. Sears–Haack body of revolution shape variation, which decreased its aerodynamic drag in compressible inviscid and viscous gas flow at Mach number of 1.8 under constraint of the volume with lower bound equal to volume of initial body, was numerically investigated.

Calculations were carried out in two-dimensional axisymmetric mode in the framework of Euler and RANS with SST model with compressibility correction equations at structured multiblock meshes. Variation of the radius as function of the longitudinal coordinate was given as a polynomial third-order spline through five uniformly distributed points. Varied parameters were increments of the radius of the body at points that defined spline. Drag coefficient was selected as an objective function. Parameter combinations corresponding to the objective function minimum under volume constraint were obtained by mixed-integer sequential quadratic programming at second-order polynomial response surface and IOSO algorithm.

Improving variations make front part of the body become slightly blunted, transfer part of volume from front part of the body to back part and generate significant back face. In the framework of RANS, the best variation decreases aerodynamic drag by approximately 20 per cent in comparison with Sears–Haack body.

The results can be applied for the aerodynamic design of the bullets and projectiles. The second important application is knowledge of the significance of the difference between linearized slender body theory optimization results and optimization results obtained by modern computational fluid dynamics (CFD) optimization techniques.

Knowledge about the magnitude of the difference between linearized slender body theory optimization results and optimization results obtained by modern CFD optimization techniques can stimulate further research in related areas.

The optimization procedure and optimal shapes obtained in the present work are directly applicable to the design of small aerodynamic drag bodies.

A Summary by Dr. Alexander Klemin of the Papers Presented Before the Fourteenth Meeting of the Institute held at Columbia University, New York, on January 29–31, 1946. AERODYNAMICS IN spite of increased wing loadings, the use of full span wing flaps has been delayed, because of inability to find a suitable aileron. The Development of a Lateral‐Control System for use with Large‐Span Flaps by I. L. Ashkenas (Northrop Aircraft), outlines the various steps in the aerodynamic development of a retractable aileron system well adapted to the full span flap and successfully employed on the Northrop P‐61. Included is a discussion of the basic data used, the design calculations made, and the effect of structural and mechanical considerations. Changes made as a result of preliminary flight tests are discussed and the final flight‐test results are presented. It is concluded that the use of this retractable aileron system has, in addition to the basic advantage of increased flap span, the following desirable control characteristics: (a) favourable yawing moments, (b) low wing‐torsional loads, (c) small pilot forces, even at high speed.

In this informal symposium, presided over by R. D. Kelly, United Air Lines, after talks, rather than the reading of papers, the pilots concerned assembled on the rostrum and answered questions. They were:

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued

Describes a novel concept in aircraft propulsion: investigates a variable cycle jet engine for a supersonic advanced short take‐off vertical landing (ASTOVL) aircraft. The engine is the selective bleed turbofan. The selective bleed turbofan is a two shaft, three compressor, variable cycle gas turbine. At subsonic flight speeds it operates as a medium bypass turbofan. It becomes a low bypass turbofan when flying faster and is capable of supersonic cruise in the dry mode. A preliminary design of an ASTOVL aircraft from Cranfield, the S‐95, was used as the vehicle. Outlines the performance of the engine and its integration with the aircraft. Explains off‐design engine performance characteristics and describes variable geometry requirements. The major advantage of this engine is that all the components are employed all the time, for all operating modes, thus incurring low weight penalties. Predicts that the aircraft/ engine combination will perform in a satisfactory way, meeting most performance targets provided that some improvements are carried out.

AT a ceremony at Lancaster House on November 29, 1962, Mr Julian Amery, the British Minister of Aviation, and His Excellency M. Geoffroy de Courcel, the French Ambassador, signed an agreement providing for the joint development and production of a supersonic air transport.