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Aviation History
1918
1918 - 1495.PDF
P ^SSe^ DECEMBER 26, 191* always that the weaving of it can be brought into line withthe peculiar qualities of flax. Certain Mechanical Limitations So far, the necessities of the case in aviation—chiefly dueto the mechanical limitations of the fabric as woven—have demanded the drawing on of the coverings endwise over thewing frames in a loose fit, depending on the subsequent taping up for the most part and then on the doping, for theadequate drum-like tightening. This condition has conse- quently endured merely in terms of hours of active flight,after which—and no great amount of service, in some weather conditions—hopeless " sogginess " has set in. And—totrace the matter back to its real root—while the weaving of the fabric remained as it did, nothing could be done. Onemerely imagined that with a different system—as for instance the incorporation of diagonal reinforcing threads, both way3athwart the matt or even the twist of the weave, so as to allow free movement in all directions, but precluding stretchin any one of them—much might be done. Indeed, that then it should be possible to revise all the more obstructivemechanical conditions. So too, with tyre fabric, which serving as a foundation forthe rubber, must not only be able to withstand enormous tensions in all directions as well as shock-stresses, but mustat the same time retain its flexibility unimpaired. Which latter idea is at once contradicted by the use of merely heavierthreads I And for aviation fabric, any extra weight per square foot is in itself objectionable, whatever the mechanicalsake or gain. The New Diagonal-Weave Loom • ' - :: . Thus it occurred to Mr. W. G. Trautvetter of Patterson, NewJersey, that the solution of the problem lay in designing a fabric which,while no heavier as to actual fibre-content, shouldhave just such diagonal threads incorporated with its regular warp and filling. This idea — or ideal — once defined,it became necessary to create practically a new model loom to weave it; for as any one with the least acquaintance•with such machines will realise, bow revolutionary must the mechanism be that would put bias threads into a weavesimultaneously with the run of the warp and filling. Hence the machine illustrated in Fig. 1 ; which, assuming,as one may fairly do, that it realises all that is claimed for it in this way, seems destined to revolutionise the weaving ofboth aero and tyre fabric : and therefore should be of the first interest to readers. Complicated as it looks, it willbe seen first that the mass of it merely consists of a drum frame, with a series of spools or winders staged in threesupon it; these feeding the actual loom in much the usual way. The further diagrams. Figs. 2, 3 and 4—all of which I takefrom the Scientific American—then become easier to follow. And The Weaving ProcessAs for instance, in Fig. 2, we see an enlarged perspective of the fabric showing how the threads run. A is the warp,B the filling and C indicates the bias threads ; and it will be specially noticed that the weft or filling threads always passunder the warps and over the bias threads. Referring then to Fig. 1, we see that these last are those which are carried inthe spools on the big winding drum or reel. Figs. 3 and 4 now show that they run to a pair of threaded screw rollers, D. Thewarps pass through the needle frame E, which constantly raises them through and above the bias threads, the shuttlespassing with the weft between both threads during this period. Now, owing to the revolving motion of the reel—theplane of which is naturally athwart that of the loom—it becomes evident that the upper half of the reel will move .the bias threads diagonally athwart the fabric in one direc- tion while the lower half will move them in counterwise inthe other. Also it will be seen that the rollers D serve to- keep them properly spaced. Or to make the operation per-haps clearer, the fingers of the needle frame pass between the diagonals and lift the warps as shown in Fig. 3. Then the .shuttle-throw carries the weft B across the fabric ; next the needle frame drops and the lay F beats the weft into place,as shown in Fig. 4. Just as the needle bar comes below the diagonals, the latter are carried by their rollers in the destinedopposed diagonal directions ; and then as soon as the bar rises its fingers pass between another set of diagonals. Thusthe diagonals are interlaced relatively to the warps, but the wefts are intermeshed between both the warps and thediagonals. The Apparent Textile ResultThe result at any rate of this mechanical thread-leading _- should be as claimed, a fabric equally strong in all directions ;and thus able to sustain—as has not been the case hitherto— diagonal strains as well as those running with or across thefabric squarely. Such a result may well revolutionise the whole aspect and technique of pneumatic tyre construction ;and at any rate, the obviously added strength without further weight can be hardly less desirable for aero-fabrics. One, itwould be imagined, that might render possible a different application to wing'frames ; more direct and to a moreaccurate fit, prior to doping, and independent of it for the, ultimate result of drum-like tightness. And if that be so, the 'final result—at least one may hazard this speculatively— might well be the elimination of sogginess, as the dope itselfwould then need to have no other function than its primary one of glazing the surface. At any rate, from the foregoing considerations, now thatthe end of the War promises greater liberty of machinery- importation, this matter of the new Trautvetter loom seems 'well worth the attention of aero-industrialists and spinners of tyre canvas. French Government and Commercial Aeronautics AN intenninisterial commission has recently beenestablished in France to deal with matters arising out of the future developments of aircraft. It will be the endeavourof the commission to establish rulings which will not hamper the development of aviation, and they will be charged withsketching out legislation which will exercise a tempered control. Such matters as direction signs, the lighting ofaerodromes at night, recognised signals of distress, &c, will come within their purview. The Commission is beingorganised by M. Rodolphe Soreau, President of the Commis- sion of Aviation of the Aero Club of France, and M. PaulRousseau. M. Soreau gives it as his opinion that Governmental aidwill be forthcoming in connection with the development of French commercial aviation, and more particularly as regardsthe exploitation of the North African Colonies. Commercial Aviation in U.S.A. CAPT. BENJAMIN B. LIPSNER, who a few days ago resignedhis position as Superintendent of the United States Aerial Mail Service, announced in New York on December 17th,that a syndicate had been formed with ^200,000 capital for establishing an aerial passenger and express service betweenNew York and Chicago The service between Chicago and New York will, he hopes, start in May with a number ofaeroplanes capable of carrying 4^ passengers or their equiva- lent in weight. Another Transatlantic Competitor CAPT. LIPSNER also stated that, unless someone should' anticipate him, he would attempt the Transatlantic flight on June 15, on a seaplane which is now being constructed. He proposes to follow the route taken by the " George Washington " on its voyage to France with Mr. Wilson oa , board. Wireless and Commercial Aeroplanes - I" > ~ ' : - IT is stated that arrangements are being made by the Marco» Company to instal on all aeroplanes engaged on" commercial service, a combined wireless and telegraph set and an efficient operator, the scheme being very much on the same lines as that which now applies to ships. General weather reports will be issued from wireless stations at home and abroad The large number of ships at sea on which there are Marconi installations will help in the complete organisation. As every aeroplane will doubtless have either a name or a distinguishing number it will be possible to send telegrams from any part of the world, or from any ship on the sea, to the aeroplane. It is intended that this organisation will be ready by the time peace is signed, and the relaxation of restrictions will allow the free flight of aeroplanes. Where the Big Machine can Help AN important part is to be played by aeroplanes in theerectiori of wireless stations in the extreme parts of China, one on the frontiers of Cashmere and the other on the Chineseside of Siberia. The necessary machinery will have to be conveyed right across China, and as there is neither railwaynor road other means of transport have been sought for. The Marconi Company has arranged with Mr. Handley Pagefor the transport by one or more of his big machines. The journey inland will take two or three days in place of thesame number of months, besides the safe crossing of a dan- gerous bit of country which would otherwise have made thescheme impracticable. I464
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