AIRCRAFT E N G I N E E R I N G 153 ing between. It seems that the time is approaching when the BRITISH STANDARDS INSTITUTION will have to go into the question Aircraft Engineering of nomenclature to clarify a position which is beginning to become obscure. Such a phrase as "thermoplastic" (as opposed to Th e Monthly Scientific and Technical "thermosetting" ) plastic is, for example, clearly not ideal with its Orga n of the Aeronautical Engineering slightly confusing tautology and yet these two terms will soon be irrevocably embodied in the literature of the subject; if that posi Professio n tion has not already been reached. There seems to be some argu ment for saying that the thermosetting varieties are no more—if Editor: Lieut.-Col. W. Lockwood Marsh, O.B.E..F.R.Ae.S.,M.S.A.E.,F.J.Ae.S. not, indeed, less—"plastic" than any of the metals. Vol. XVI. No. 184 June, 1944 The Plastic Age However that may be, it seems more than possible that we are E publish in this issue, by courtesy of the Institute, two nearing something approaching a "plastic age". We are impressed papers recently read before the ENGINEERING INSTITUTE OF with the experiments carried out by the CANADIAN NATIONAL CANADA by members of the staff of the National Research RESEARCH COUNCIL, described by MR. HISCOCKS, in the making of Council on plastics and allied materials. Following as it does the control surfaces, and a complete rear fuselage, for the Harvard in description of the Duramold "electronic" process of gluing which what he calls "plastic plywoods "—a term which seems to confirm appeared in these pages last month, Mr. W. GALLAY'S paper is of the difficulty in distinguishing between the two materials, to which particular topical interest because it deals with another method of we have confessed above. It certainly does not seem as certain as electrically heating the "glue line" developed in the Division of it did to many people only a little while ago that the "plastic Chemistry at Ontario. Both systems have been evolved to over aeroplane" is merely the idle dream of fanatical enthusiasts. He come the difficulty of applying heat to "cure " the adhesive with would, we feel, be a bold man who would say that it is inherently out the wood being involved, but Mr. GALLAY'S system seems to go impossible, or even unlikely; though how far the material will a stage further by avoiding the use of special electric equipment prove better or worse than others, in strength/weight ratio or ease and only calling on the normal supply. We are not familiar with of production, it is too early, perhaps, to express any realistic " acetylene black " and do not know how far this is available in opinion. England. Its adoption ingeniously avoids the incorporation in the We are not, of course, attempting to prejudge the issue and no one glue of substances likely to affect its qualities. can yet say how far plastics as a constructional material will be able to compete with the. metal alloys at present in use on a strength/ The Ground Covered weight ratio. Enthusiasts for the new technique are already mak The materials generically known as plastics—though they cover ing claims the justification, or otherwise, of which time alone will a range with widely differing characteristics—are gradually emerging show. It does, however, appear from the Canadian experiments that out of the mists tha t have been enshrouding them, with the evolution at any rate some parts of an aeroplane can even now be produced to of methods of dealing with them, and the ordinary engineer can now give adequate efficiency—as we have said the development of this begin to get a picture of their possibilities and limitations. As it promise rests with the future. It does seem, at any rate, that pos chances, in this same issue appears a brief summary by PROFESSOR sibly in this direction lies the best hope of the truly monocoque KLEMIN of two papers on the use of wood—both natural and "im structure for aeroplanes which is, we suppose, an ideal to be aimed at. proved"—which seem to cover somewhat the same ground as the There is no doubt whatever, as the increasing literature on the sub second Canadian paper by MR. HISCOCKS. Following on the ject shows, a very great deal of energy being put into the improve description of the design and construction of the Mosquito by M R ment of all the qualities of plastics and very rapid strides have been MCINTYRE in March this year—also through the good offices of the made in the last two or three years. ENGINEERING INSTITUTE OF CANADA—we have a very complete picture of present practice and likely development of the immediate future. We may perhaps be permitted to recall that wood as a AN ANNUAL EVENT constructional material for aeroplanes in its modern metamorphoses has received full consideration in the pages of AIRCRAFT ENGINEER- In this issue we start publication of PROFESSOR KLEMIN'S cus ING. So long ago as 1938 we published translations of two tomary summary of the papers read at the Annual Meeting of the German papers on " Wood as a Homogeneous Material " which were INSTITUTE OF THE AERONAUTICAL SCIENCES, the rest of which has followed in 1940 by a far-sighted series of four articles by MR. WEY L had to be held over till next month. We wonder if the American on " Modern Wooden Construction " which will bear fresh reading members appreciate how fortunate they are in having only the even to-day. minor difficulties mentioned by him to overcome. They could at any rate make plans in advance for the holding of the meetings as usual ; The authors of both the papers read before the INSTITUTE OF THE- with us fears that the place of assembly might meanwhile have AERONAUTICAL SCIENCES agree that it is the appearance of synthetic ceased to exist through enemy action; or that the travelling of so resin adhesive that has, as it were, put wood "o n the map"—a s is, many people for the purpose might be so frowned upon as to be in indeed, obvious; though it must not be forgotten that trainers are effect prohibited owing to their country being the training and being constructed both in England and America, and at least one assembly ground for an invasion force on a large scale. We are very operational type in Russia, of " pure " timber. conscious that by contrast with the occupied countries of Europe England's sufferings have been almost infinitesimal but even they A Question of Terms offer some contrast to the complete inviolability enjoyed by the We may seem to be confusing plastics with wood but, truth to tell, soil of the United States. It is none the less good that someone it seems to us tha t the two are so tending to merge into one tha t it is somewhere should still have the opportunity to chew the cud over becoming difficult to draw a hard and fast line between them. As a year's progress and development, and many of the papers appear one goes from solid timber through plywood (with the grain in the to have been of the high standard to be expected from past ex ayers set at an angle to each other) to laminated wood (with parallel perience. arrangement of the grains) closely impregnated with resin adhesive and from there to the completely homogeneous material consisting of PROFESSOR KLEMIN seems impressed by the attendance at the wood fibres embedded in a resinous surround, it becomes increas rotating wing meeting, but we cannot help wondering how far this ingly difficult to decide precisely where wood ends and plastic begins. may not have been influenced by the prospect of seeing films. In the hot-pressed laminated wood differs, as it seems to us, only in our experience, it is astonishing how even the most technically the medium used as the "carrier" for the resin from the fabric- sophisticated assembly reacts to the lure of a moving picture, strengthened plastic—with the Togo film and its counterparts com while it will remain completely unmoved by a "still" of a graph.
Aircraft Engineering and Aerospace Technology – Emerald Publishing
Published: Jun 1, 1944