FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1922
1922 - 0412.PDF
JULY 20, 1922 THE HANDASYDE MONOPLANE, TYPE H.2 Rolls-Royce " Eagle" Engine ONE of the most interesting machines which we have had the opportunity of seeing is now nearing completion at the Bleriot Works at Addlestone. The machine referred to is the new Handasyde monoplane, designed by Mr. G. H. Handasyde, of the Handasyde Aircraft Company, for Australia. Being at the moment without works for manufacturing aircraft, the Handasyde Aircraft Co. have made arrangements with ,JMr. Chereau for the construction of a batch of these machines at the Bleriot Works, and here we had the opportunity of inspecting the machines last week for the purpose of com piling the following notes, and obtaining the accompanying illustrations. It should be pointed out that, at the time of our visit, no drawings were available of the engine cowling and undercarriage. Although as regards general lay-out the accompanying scale drawings are accurate, the portion relating to these two items should be taken as representing the general idea only, and is not guaranteed to be exact as regards dimensions, as we were unable to obtain certain necessary information relating to wheel track, size of wheels, etc. For the rest, however, the scale drawings on p. 413 may be taken as being accurate. General Design To those who have followed the development of flying since its earliest days it will not come as a surprise that the new H.A.C. machine is a monoplane. From the very first Mr. Handasyde was a great believer in the monoplane, and it will be remembered that his early machines, round about 1911, 12 and 13, were of this type. During the War Mr. Handasyde turned his attention to biplanes, not because he had lost his faith in the mono., but as a result of the demands of the R.A.F. He proved that he was quite as capable of designing biplanes as monoplanes, and probably his F.4 is the most beautiful aeroplane that has ever been produced. It must be admitted that, purely as regards appearance, the new monoplane is not up to the F.4, but probably this was impossible of attainment in a monoplane type. The new machine, which is of the cantilever type, is characterised, in the matter of construction, by being built almost entirely of wood. Metal is used very sparingly in the construction, and the manner in which the wood has been used is everywhere interesting and, in places, highly ingenious. The Fuselage .The fuselage is built up of a framework of four main longerons, a certain number of stringers, and shaped formers or bulkheads. The covering is three-ply wood. Although the main frame work is of rectangular section, the cross- section of the complete body is rounded, the flat sides, top and bottom having been brought up to a rounded section by curving the formers and bending the three-ply covering over them. It is an old axiom that one can bend three- ply sheet over a single but not over a double curvature. In other words, although it can be bent over a cylinder, it cannot be bent over a barrel. In the Handasyde H.2, as the new machine is called, it would appear that an attempt has been made to bend the three-ply covering over a barrel. On closer examination, however, one discovers that the old saying has not been disproved, since here and there it has only been possible to persuade the ply-wood to bend by sawing little vee-shaped pieces out of the ends. By using smaller panels elsewhere, the desired curvature is obtained, or, more correctly speaking, the curvature consists of several relatively small straight faces. The four main longerons are of ash, while the simple struts and stringers are of spruce. The shaped bulkheads or formers are built up into box sections from ash flanges and three-ply walls. A noticeable feature of the fuselage, which, incidentally, has also characterised Handasyde-designed biplanes, is that all tapers are straight, with the longerons butt-jointed and the joints reinforced by fish-plates of generous area. Thus in the H.2 the cabin portion of the fuselage is one piece, with the longerons running parallel. To this portion the rear part of the fuselage is joined and runs in a straight taper to the tail. Similarly, the part of the fuselage which is in front of the cabin is of straight taper, with joints well secured by large fish-platea. I The Monoplane Wing Perhaps the most interesting feature of the machine is the manner in which the wing has been built up. Aero- dynamically also the -wing is interesting, on account of the sections employed, which taper from a deep bi-convex section at the root to a very thin section, with perfectly flat bottom camber, at the tip. So far as we were able to discover, there is no change in the angle of incidence along the span : in other words, there is neither " wash-out " nor " wash-in." Constructionally, the wing is interesting ; first, on account of the fact that it is built up on four main spars, and, secondly, because of the unusual wooden covering which takes the place of fabric. From the plan view of the general arrange ment drawings, it will be seen that the wing, which is built in two halves, joined on the centre line, has a pronounced taper from root to tip. The front main spars are parallel, the. others tapering so as to fall always at the same percentage of the chord from the leading edge. The use of more than two., spars in a cantilever wing has previously been advo cated in this Journal as being more economical, but up to the present no machine except the new Handasyde has been built in this country which incorporates this feature. The construction, quite apart from the number of the spars, is interesting. Obviously with four spars each can be built much lighter and the usual forms, such as simple I sections or box sections may not necessarily be the best. The form which the spars of the H.2 take is a built-up I section, with a thin web of two-ply spruce and divided flanges of the same material. The web is built up of two thicknesses, each composed of thin strips about 4 inches wide crossing the other at right angles, each crossing the horizontal at 45 degrees. In order further to strengthen the web, its two sides are covered with fabric. The flanges, which are made up of two strips each, have their halves screwed and nailed through the web, which comes up to the level of the outer faces of the flanges. Between the spars there are two sets of stringers, one set on the upper surface and one on the lower, and the ribs^which are of a construction somewhat similar to that of the spars, are notched to receive the stringers. The ribs are built up of thin three-ply webs, stiffened with vertical and diagonal pieces of spruce, having two sets of flanges, one of which passes inside the stringers and the other forms the outer flanges. The sketches will serve to indicate the construction. All ribs project past the stringers and come up to the level of the wooden wing covering. Where local loads occur, such as, for instance, the petrol tanks, the attachment of the undercarriage struts, etc., double ribs are used, whose construction is also shown in the sketches. Both single and double ribs have the outer flanges running across the spars, and the shear stresses are taken by the inner flanges and three-ply webs resting against the inner faces of the spar flanges. Interesting as is the construction of the spars and ribs, the wing covering is even more so. Although it appears possible that the wood covering takes a certain part in supporting the load, the manner of applying the strips of which it is composed is such that no allowance has been made for this in stressing the wing. The covering consists of spruce strips approximately J inch thick and about 4 inches wide, laid parallel in a fore and aft direction. In order to lighten these strips, they have been spindled out, leaving narrow ridges the full depth of the thickness of the strips. It was noticed that where the strips are bent over a fairly steep curve, the spruce covering strips, or planking, as one might term them, had sagged between these ridges, much as does the fabric between ordinary wing ribs, but, of course, to a much smaller extent. There is no internal drag bracing; as the wing planking, running fore and aft, is capable of resisting drag stresses. The leading edge of the wing is formed by TlB inch three-ply, packed up by strips on the front spar to come level with the thicker spruce covering. We have no figures relating to the weight of the wing, but Mr. Handasyde informs us that, although heavier per square foot than the ordinary thin wing with bracing, in view of the high lift coefficient of the thick section, the wing comes out quite light. Naturally the first wings have been very ex pensive to build, as jigs, etc., had to be erected, but it is thought that for production in quantities the construction will not be unduly expensive. The finished wing certainly looks a beautiful piece of work, and we think Mr. Chereau is to be congratulated upon the manner in which his works have carried out a difficult piece of construction. The attachment of the wings to the fuselage is very neat and simple, and should prove very satisfactory. On the four formers in the cabin, near the top longerons, are metal fittings, roughly of T shape, with the one arm of the T projecting out through the fuselage covering. As there is 412
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
