FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1912
1912 - 0946.PDF
[/ycSf OCTOBER 19, 1912. MODERN WING SECTIONS. Tin; sectional sketches of wings that occupy pages 944 and 945 of this issue are published in the interests of those who are unable to attend the various centres where they might frequently see the actual machines on which the wings in question exist; but they are not published with any pretence at being geometrically accurate, for the conditions under which they were prepared scarcely permitted more than a resemblance to the reality to be obtained. It was down at Salisbury Plain during the Military Aeroplane Trials that these sketches were made, and they originated from a desire to compare the salient points of the wing sections of the various competing machines. When you try to remember features of this kind while wandering from one machine to another, you are more than apt to become hopelessly confused by the time you have inspected a dozen or so, unless you make a point of putting down on paper the characteristics that strike you about each wing while you see it. And each of the wings illustrated does certainly possess the characteristics that are most prominent in these rough sketches, notwithstanding that the sketches themselves may be much out of scale. In some cases, they were made by the designers themselves, but in all cases they were at least drawn with the assistance of some responsible person who was thoroughly familiar with the machine. Thus, notwithstanding their in accuracy as scale drawings, they may fairly be regarded as characteristic pictures of what the eye sees when looking at the wings. Directly one has collected a set of sketches like these, their interest is self-evident, for it would be difficult to imagine any collection with more diverse characteristics. Moreover, what is so interesting about the matter is that every designer seems to put great faith in the virtues of his particular wing section, and yet, to judge from the variety of contours in this collection, one might be pardoned for doubting whether any one of them possessed merit above another. At any rate, they all fly, so whatever special quality may appertain to particular shapes it would seem that its investigation is more properly related to laboratory research, such as, for example, that conducted so patiently by M. Eiffel—and even his results, some people consider, should be read with discretion. • In the matter of these sketches, however, it is not our purpose to attempt to dilate upon the merits or otherwise of the wings represented; it suffices to draw attention to the extraordinary differences between one wing and another. Indeed, although the wings illustrated cover practically all the important aeroplanes in the Trials there are scarcely two sections alike. The closest resemblance appears to be between the Bristol mono plane and the Hanriot, both of which have a peculiar entry causing a reversal of curvature under the front main spar. The Hanriot has a flattened top, which appears less pronounced in the Bristol monoplane, ® $ Col. Cody Again Wins Michelin Cup No. 2. ON Saturday last Col. Cody succeeded in flying round one of the stipulated courses for the British Empire Michelin Cup No. 2, and as he was the only one to comply with the conditions—which stipulated that the machine and engine must be all-British and piloted by a British subject—he has now been awarded the prize. Starting from Farnborough at 11.50 a.m., on the machine which won the recent Military Trials, which has now been fitted with a 100-h.p. Green engine, he made Salisbury Plain without incident, and then got somewhat off his csurse owing to the fog, and found himself over the sea at Southampton instead of Newhaven. He, however, followed the coast to Newhaven, and from there had no difficulty in where the camber is gradual but appears to be regularly maintained. Both wings have a slight reversal of curva ture in the run so that the trailing edge is, as it were, washed out. The trailing edges of these wings, however, are not specially flexible, as it is on the Breguet for instance, where a somewhat similar characteristic is noticeable, then considering the Breguet section, it must be borne in mind that the ribs only have to contend with one main spar, to which they are attached by spring-like hinges. The necessity of encircling two spars, governs very largely the shape of any wing section that can be satisfactorily constructed, and especially is this the case when the spars lie far apart or when they are of equal depth. The Avro is an example of a wing section surrounding two spars of equal size, and is a perfectly rigid rib from entry to trail. The under surface at the point of its entry is flat. Two other examples of wing sections that tend to facilitate equality of spar section are the Eiffel curves used on BE 2 and the Coventry Ordnance. Of these XIII ins brings the maximum top camber further forward than is the case with No. 8. There is an interesting distinction between the top and bottom planes of the Flanders biplane, but in most of the other biplanes the top and bottom members seem to be alike. There were, however, some slight distinc tions between the wings of different monoplanes of the same make, as, for instance, may be seen by comparing the British with the French Deperdussin and Bleriot No. 4 with Bleriot No. 5. The French Deperdussin has a slightly more pronounced dip on its leading edge than the British model, and the same remark applies to the Bleriot sociable as compared with the Bleriot tandem. Two of the most extraordinary wing sections are the Handley Page and the Cody, especially when seen together as they are in these sketches. The Handley Page has an immense depth of front spar but it must be remembered that the wing is crescent shaped and that the camber as well as the angle of incidence varies from shoulder to tip. At the tip it is almost entirely a washout, and the object of the design is to produce a well graded loading over the span. Compared with the Handley Page, the Cody looks a very lean rib, especially as it has a flattened top surface between the spars, which gives it a kind of waist. The under surface of the Cody is one continuous smooth curve from behind the front spar. It is interesting to note the similarity of characteristics, but on an entirely different scale, between the Cody and the Hanriot, both in respect to the flattening of the top surface and in the shape of the entering edge. Whereas most wing sections are designed to drop the top surface sharply downwards to meet the bottom surface at the point of entry, the wing sections just mentioned reverse this principle by curving the under surface sharply upwards round the front spar. ® ® finding his way, via Brooklands, to Farnborough, where he arrived at 3.16 p.m., having taken 3 hrs. 26 mins. for the trip, the official distance being 186 miles. A Try for British Michelin Cup No. 1. ALTHOUGH he had only had a short practice on the machine the previous day, Mr. Hawker started at 6.51 a.m. on Wednesday morning last, on the new Sopwith biplane with twin propeller, fitted witha40-h.p. A.B.C. engine, for a try for the British Michelin Cup No. 1. This cup is offered for the longest duration flight on an all-British machine made before October 31st. After he had been in the air 3 hrs. 31 mins., mostly at a height of about 500 ft., a valve spring broke, which necessitated a descent. 946
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
