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AERONAUTICS owes much to the selfless devotion and enthusiasm of its early pioneers. As was noted by the author in the Fourth Lanchester Memorial Lecture,1 Queen Mary College can claim to have the oldest established University Department of Aeronautical Engineering in the country due to the pioneer work of Dr A. P. Thurston, a graduate of the College, t It was in 1908 that he decided to establish an Aeronautical Laboratory there. He inspired the interest and support of like‐minded friends and Mr P. Y. Alexander, in particular, contributed a major part of the funds required to equip the laboratory. From Professor J. L. S. Hatton, the then Principal of the College, Dr Thurston received warm encouragement and the space for the venture, but College funds were then less than adequate for its longer established activities, and so the College could not afford to offer financial support to the new venture in its early days.

WITH reference to the article on the “New Transformed Wing Sections,” by Piercy, Piper and Whitehead, (P) in the November, 1938, number of AIRCRAFT ENGINEERING, it is of interest to note a very simple approximate formula for the symmetrical type of section. This formula is:

THE basic method of air navigation is deduced reckoning or simply dead reckoning. The method comprises the maintenance of an air pilot, which is made by calculating true airspeed and hence air distance run and then plotting this along the aircraft's heading from some initial ground fix. Subsequent ground positions may then be deduced by laying off the wind vector from the air position. As an example (Fig. 1) suppose an aircraft flics for one hour on a true heading of 060 deg. starting from an initial ground position A. If the true airspeed is 180 knots the air position will be at B, and if the mean wind over the flight is 45 knots from 340 deg. true then the ground position (by D.R.) corresponding to an air position at B would be at C. Now if the aircraft flics for the next hour on a true heading of 085 deg. and the mean wind over this hour is 30 knots from 310 deg. true, the air position with respect to A would be at D and the ground position at F. If a new air plot had been started at C then the air position, at the end of the second hour, would be at E and the ground position (by D.R.) again at F.

ANOTHER paper (Ref. 1) establishes a new approximate solution of the boundary layer equations devised to meet difficulties that are encountered in applying earlier solutions to laminar flow aerofoils and similarly thin cylinders. The advantage is in respect sometimes of accuracy, sometimes of applicability. The solution is a little unwieldy in its general form, however, and the present paper describes simplifications to facilitate rapid technical use. They are of two kinds, one being much more drastic than the other, and that first given, or both, may be used according to the nature of the problem and the accuracy required. Examples suggest that the resulting loss of accuracy and applicability will be small in most instances. This matter is described in Section I.

THE study of the flight of birds has provided and will still provide much valuable information for tiie progress of human flight. Many suggestions for the improvements of wings by the use of special wing tips owe their existence to the observation of nature. In spite of such suggestions, free‐flight experimentation—as far as published work goes—is still rather rare and restricted in scope. This reluctance may be due to practical design considerations (handling) as well as to the necessity of making the conventional aileron as efficient as possible; it may also be caused by the impression that experiment in this direction is not worth the effort.

(1) Theoretical consideration of aerofoils of limited span led, in Article III, to a need for some assumption as to lift‐grading along the span, to give the span‐grading of circulation. Fig. 1 shows at (a) the experimental distribution of lift along a rectangular aerofoil of 7·6 per cent camber and aspect ratio 6, at an angle of incidence of 6 deg. At (b) elliptic loading is shown, which, from several points of view, may be regarded as ideal for the same lift coefficient. Assumption of the latter form permits of greatly simplified treatment. Even compared with rectangular aerofoil distribution, the assumption gives differences of little importance in many practical calculations, while these are still less with aeroplane wings, owing to the wash‐out usually introduced at their rounded wing‐tips. The following is, therefore, restricted to elliptic loading, but sufficient generality of presentation is preserved to allow, if desired, other forms to be substituted.

AIRCRAFT ENGINEERING was born at the very beginning of a period of great developments in aeronautics. For over a decade the steady improvement in the performance of aircraft had been due almost entirely to the efforts of engine designers, and their very success tended to obscure the deficiencies of aeroplane design.

IT is a matter for congratulation that we are able to publish this month the fully illustrated article, describing the production of a prominent type of modern aero‐engine, written by Captain J. C. Briggs. We are sure that our readers will join us in warmly thanking Armstrong‐Siddeley Motors Limited for thus revealing the details of their methods. This is a public‐spirited action which cannot be too warmly commended, but which is, unfortunately, far too uncommon—at any rate in England. In some other countries, notably America, designers and manufacturers of air‐craft are always ready and willing to lay their cards on the table and reveal their “secrets.” In England, on the other hand, there is in general a very different attitude of mind, and there is an almost universal feeling that aeroplane production methods are matters to be maintained as closely‐guarded secrets. This is a curiously ostrich‐like policy which is difficult to understand. After all, it usually comes down in the end to the more or less detailed adaptation of tools and machines of general commercial design to special uses. The details of the products turned out cannot be kept hidden, since the whole object of them is that they shall be placed on the market. The attitude of jealousy argues a self‐satisfaction and complacency of mental outlook that can seldom be justified. One would have thought that no one, even a production engineer, would be so certain of his pre‐eminence that he had nothing to learn. And yet if he is unwilling to publish his own methods how can he expect others, from whose experience he might profit, to do so? Furthermore, one would have thought that he would welcome the criticisms that might come from discussion; as they would inevitably, one would imagine, bring fresh ideas to a man of original and inventive mind. Even if, he might say to himself, none of his methods could in themselves be open to direct criticism there might none the less be ideas for detailed improvement to be gained from discussion.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued

AN approximate solution of the boundary layer equations recently completed involved the assumption of a velocity profile through the boundary layerdepending on two parameters. As a result the problem was reduced to that of the construction and solution of two equations governing the variation of these parameters around the surface of the cylinder considered. Earlier solutions, such as Pohlhauscn's, have made use of a single parameter only and have employed Kármán's momentum integral for its determination, but the additional, parameter now introduced necessitates the use of a further equation. It is the purpose of the present note to discuss and illustrate the properties of the second condition that was selected.