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MANY hold the view that the attainment of very high speeds of flight will be prohibited by the excessive skin temperatures involved, particularly in the vicinity of the wing leading edge, at least until that time when unforeseen advances in metallurgy, or in the application of ceramics, enable the extraordinary problems involved to be overcome. As an opinion it may for all one knows be justified by the event, but it seems (at least to the author) to exaggerate the facts, because it surely ignores the important role played by the conduction of heat along the skin in limiting the temperature. It is the intention of the present article to convert others to this way of thinking.

IS there anything magic about the shape of a wing section? Asked to sketch the profile of a wing on the back of an envelope, one would have no difficulty in representing a shape which would probably, for most purposes, be adequate. Assuming this generalization to be true—perhaps it is a rather rash one—one might equally well question the need for an article on aerofoil design, or indeed the need for the long and painstaking research which, over the years, has been conducted on this particular subject. But it is this same research which, in the long run, has resulted in the recognition of certain general rules relating to aerofoil geometry, which are now taken so much for granted that they would probably be embodied in one's preconceived notion of what a wing section should look like. Recently, also, rather complicated theoretical techniques have made possible the design of profiles which, if manufactured faithfully and carefully in each detail, can provide a performance which is considerably better than any more arbitrary shaping to general rules would produce. Finally, of course, one must recognize that there are exceptional conditions where the application of conventional ideas is inadvisable, and where theoretical and experimental research is needed to suggest what is more appropriate. This article will be concerned for the most part with amplifying these remarks; but, by and large, it must be admitted at the outset that we cannot point to any revolutionary discontinuities in the progress of aerofoil design such as have characterized advances in the means of aircraft propulsion, or structural design.

THERE have been various suggestions that the return of man from his trips of exploration into space may best be effected by glider. The design of such an unusual form of aircraft will present many unusual and difficult problems, and here we shall merely be content to remark upon those which fall into the category of stability and control.

We shall attempt here to summarize the existing data on the values of the low‐speed CLmax. of wings, in the absence of a fuselage, and without including information on stalling incidence or pitching moment. The summary is limited to the consideration of unswept wings, and those of delta plan form, which have symmetrical sections: there is some discussion of the maximum lift increments due to the use of flaps of various kinds.

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.

WRITING an introduction to an article by Mr S. B. Gates on Trailing‐Edge Flaps, which appeared in these columns in 1937, the Editor felt constrained to admit his bewilderment over the number and variety of types of high‐lift aid which then existed. Without intending any disrespect, I imagine that the progress of years must have added to his embarrassment. It has certainly added to the number of devices in use and under test.

Waverider has high lift to drag ratio and will be an idea aerodynamic configuration for hypersonic vehicles. But a structure permitting aerodynamic like waverider is still difficult to generate under airframe’s geometric constrains using traditional waverider design methods. And furthermore, traditional waverider’s aerodynamic compression ability cannot be easily adjusted to satisfy the inlet entrance requirements for hypersonic air-breathing vehicles. The purpose of this paper is to present a new method named osculating general curved cone (OCC) method aimed to improve the shortcomings of traditional waveriders.

A basic curved cone is, first, designed by the method of characteristics. Then the waverider’s inlet captured curve and front captured tube are defined in the waverider’s exit plane. Osculating planes are generated along the inlet captured curve and the designed curved cone is transformed to the osculating planes. Streamlines are traced in the transformed curved cone flow field. Combining all streamlines which have been obtained, OCC waverider’s compression surface is generated. Waverider’s upper surface uses the free stream surface.

It is found that OCC waverider has good volumetric characteristics and good flow compression abilities compared with the traditional osculating cone (OC) waverider. The volume of OCC waverider is 25 per cent larger than OC waverider at the same design condition. Furthermore, OCC waverider can compress incoming flow to required flow conditions with high total pressure recovery in the waverider’s exit plane. The flow uniformity in the waverider exit plane is quite well.

The analyzed results show that the OCC waverider can be a practical high performance airframe/forebody for hypersonic vehicles. Furthermore, this novel waverider design method can be used to design a structure permitting aerodynamic like waverider for a practical hypersonic vehicle.

The paper puts forward a novel waverider design method which can improve the waverider’s volumetric characteristics and compression abilities compared with the traditional waverider design methods. This novel design approach can extend the waverider’s applications for designing hypersonic vehicles.

THE work of Johnson, Mathur and Henderson on the ‘Creep Deflexion of Magnesium Alloy Struts’ raised the question in the present writer's mind of the stress distribution in the beam cross‐section, and the variation of this distribution with time. The precise computation of the stress distribution in an eccentrically loaded strut appears to be a very difficult problem, and the present note is concerned with the much simpler case of a beam subjected to a constant bending moment.

In the preface it is stated that a need exists for a ‘comprehensive treatment of the subject that will present fundamentals in broad perspective but without emphasis on any one type of system’. The book is written as a single volume introduction to the subject so as to fill this need in part. The missiles dealt with in the book are what, in this country, would be more properly called guided missiles; the author states that the broader description ‘advanced’ was adopted to avoid implying any unintended restriction upon the applicability of basic principles. The book is competently written and a number of diverse technical aspects are handled in a workmanlike manner. There is a refreshing soundness and depth to the book which regrettably is not often found in books on guided missiles from across the Atlantic. To cover a subject embracing so many different techniques in a book of less than 600 pages is, of course, a difficult task. The treatment on the whole therefore has to be concise. This in itself is not a failing as the reader will generally be expert in at least one of the areas and will gain enough from the book to refresh his memory and enough to see what are the main features applicable to guided weapons. In areas where the reader is less well trained it will be necessary for him to supplement the text by reading elsewhere. To aid him in this the book is adequately provided with references (without overburdening the text). The treatment is a formal presentation of the basic theories, emphasising the common ideas underlying, for example, signal detection in the presence of noise and quality control. The reader would finish the book with a sound idea of the fundamentals but with only the vaguest idea of how to set about the design of a missile. What is required is a sequel to this book where the logical design, say, of three or four types of missiles is worked through with a generous number of examples.

THE paper selects for brief discussion a very few of the successful aeronautical researches conducted in the United Kingdom in recent years. The selection includes illustrations of the work of government establishments, of industry, and of universities. Moreover, the choice made is intended to exemplify the principal fields of activity of the Aeronautical Research Council, as represented by its standing committees and group of special committees: aerodynamics, mechanics, propulsion, and special topics. The paper concludes with a plea for continued research on as large a scale as possible.