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AT a time when the name Handley Page is continually in the news, we are privileged to announce that our next issue will contain Part 1 of an article entitled ‘Boundary Layer Control for Low Drag’, written by that acknowledged international authority on the subject, Dr G. V. Lachmann. As Director of Research with the Handley Page Company, Dr Lachmann has been responsible for maintaining this country's stake in the development and application of laminar flow techniques, and it is a sad commentary on Ministry of Aviation policy that while sponsored work is being carried out in the United States with a view to flight testing full‐scale laminarised aircraft, the Handley Page Company has been obliged to continue its work without the substantial financial backing which only a Government contract could provide.

THE change from the parallel wings of the now obsolescent biplane to the tapered wings of the monoplane, usually fitted with flaps, raised a great number of problems, both aerodynamic and structural. Work on these has been pursued vigorously during the past few years, but the designer is still some considerable distance from having all his questions answered. For instance, further information is required as to the relation between wing thickness and profile drag before it can be decided what is the maximum thickness which can be used, taking both aero‐dynamical and structural considerations into account. This question is complicated by the fact that, so far as the tip sections are concerned,. the indications are that the thickness ratio has important effects on the nature of the stall, violent or gentle. So, too, will such factors as centre line camber and position of maximum ordinate affect the nature of the stall in greater or Jess degree. Added to these factors there is, of course, the important one of the taper itself, including—as is now realised—the question as to the way in which the tapering is done, that is, whether by sweeping the trailing edge forward or the leading edge back, or, as is more usual, a combination of the two.

Since the end of the Second World War, many spectacular advances have been made in aeronautics, thanks chiefly to the development of more powerful and economical jet engines. As to the parasitic drag of manned aircraft, progress has been confined to reducing unfavourable compressibility effects (area rule, Whitcombe bodies); methods to suppress separation have been developed but no new methods to reduce the drag resulting from turbulent boundary layers developing over the exposed surfaces have as yet found practical application.

MR. SERBY'S article on trimming and balance tabs gives a very concise theoretical explanation of the working of trimmer and balance tabs, and explains certain characteristics which have baffled most designers.

OPTIMIZATION of wing design aims at finding the best compromise between conflicting aerodynamic requirements and considerations of structure weight and stiffness. Since the profile drag of a laminarizcd aircraft is very small, the induced drag has to be correspondingly reduced for proper matching. Reduction of induced drag can only be obtained, for a given dynamic pressure at the cruise, by increasing the span, and that reflects on structure weight.

IT seems rather strange that while the general property of wing flaps of putting up both the lift and the drag of a wing at the same time has been known for many years, so little practical application of this result has been made until quite recently.

A FUNDAMENTAL method of determining the distribution of lift across the span of, e.g., a monoplane wing is that of Graphical Successive Approximation, proposed originally in 1923 by A. Fage and B. N. Jurieff independently.

THE fundamental problem of aerofoil theory is to predict accurately the characteristics of wings of various sections and plan form when the former may be any function of the latter. The vortex theory of aerofoils enables us to predict the chief properties of aerofoils below the stall. We are, however, interested also in the conditions obtaining at and above the stall. In the present state of the art we are obliged to rely on wind tunnel tests. The number and variety of wings that would have to be tested in order to give us at all a comprehensive survey of the possibilities of taper, aerodynamic twist and varying section are so great that wind tunnel tests can so far only be said to have touched the fringe of the problem.

THE basic theory of stability has undergone no important modification since the publication of Professor G. H. Bryan's book on Stability in Aviation in 1911. The stability equations derived therein serve to‐day with the difference that axes and symbols have now been standardised and with the additional refinement of a non‐dimensional form of the stability equation introduced by H. Glauert. Due to the vastly increased knowledge of aerodrynamic characteristics, however, the stability derivatives are more readily assessable in any particular design case. This applies more particularly to longitudinal stability calculations which may, and indeed often arc, carried through with no wind tunnel tests available apart from a lift and drag curve for the aerofoil section used. There has also been some extension of the use of stability charts for deriving an approximate knowledge of the behaviour of the aeroplane when it receives a disturbance. These charts are exceedingly useful for obtaining periodic time and damping factor, but the assumptions on which they are based should be clearly realized.

I PROPOSE to review the company history firstly by reference to some of the many types of aeroplanes and projects it has engaged upon. A major difficulty arises in that to date the aeroplane type numbers used within the company already exceed 140. Of necessity, therefore, the types mentioned must be strictly limited.