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THE INDIA RUBBER WORLD 



[May 1, 1912. 



RUBBER AND AVIATION IN FRANCE. 



By Rene Bobet. 



THE numerous applications of rubber to aviation include 

 four main classes of products, very different in char- 

 acter: 



I. Wheels with pneumatic tires ; 



II. Rubbered fabrics for the wings ; 



III. Mechanism for breaking falls; 



IV. Aviation equipment. 



Each of these branches will be considered separately. 



PNEUMATIC TIRES. 



All the wheels used on aeroplanes have pneumatic tires. The 

 wheels consist of a metal rim, of an air chamber with valve, and 

 of a tire; being constructed with bicycle or motorcycle axles 

 and metallic spokes, so as not to increase the weight. The 

 tires are sometimes made with wires and sometimes in the 

 clincher style; being cemented on by hand. 



When aviation started, people were satisfied to use bicycle 

 wheels. Today the types of wheel employed are very numerous, 

 varying in each instance; it being thus rather difficult to give a 

 complete list. Aeroplanes are seen with wheels from 10 to 28 

 inches in diameter, and from Ij^ inch to 3j4 and even 6 inches 

 in thickness. Over 20 separate sizes are formed by combinations 

 of these dimensions. Owing to the fact that the clincher tire, 

 while suitable for motorcycles or for automobiles, is perhaps 

 a little heavy for aeroplanes, many constructors of the latter 

 prefer to use tires with rods. The latter have the advantage 

 of being lighter, and moreover the weight and resistance can 

 be very easily varied by altering the number of layers of fabric 

 and the thickness of the rubber, while combining the various 

 dimensions. 



There is a tendency to eliminate small pneumatic tires, Ij^ 

 to 154 inch thick of the bicycle type, which are really too small 

 and are being replaced by pneumatic tires of 2, 2j/2 and 3J4 

 inches, mounted on wheels of 20, 26 and 28 inches in diameter. 

 Most aeroplanes have two wheels in front and one behind. Some 

 have four in front on same axle ; two at each side. 



RUBBERED FABRICS. 



The wings of aeroplanes are covered with fabric possessing 

 extreme resistance. Some constructors are satisfied with using 

 varnished or oiled fabrics or even ordinary materials, but most 

 frequently rubbered fabrics are used. These fabrics ought to be 

 very light and yet very strong, being, moreover, waterproof, so 

 that in case of rain the aeroplane would not be weighted ; the 

 rubbering being on one side or both sides. It is effected by the 

 rubbering machine or spreader ; the fabric receiving several layers 

 of Para solution, so as to ensure very regular application. 



The following table illustrates some fabrics : 



Weight, Resistance 



Width, sq. yd., in ozs. per 



Designation of fabric. inches. in ozs. sq. yd. 



Ordinary cotton fabric 42 4 29j4 



Light cotton fabric 47 i% 24 



Very light cotton f.nbric 47 3^ 13^2 



Silk fabric 35 3J4 32^4 



Linen fabric 51 4J4 42 



Heavy linen fabric 42 5j^ 52J/2 



Aeroplane wings fitted with rubbered fabrics present more 

 security than those with ordinary fabrics, being on that account 

 destined to be more and more used by aviators. 



FALL-BREAKING APPLIANCES. 



Aeroplanes are usually provided with landing cars in combina- 

 tion with fall-breaking systems in such a way as to protect the 



aviator and the mechanism against concussions of too violent a 

 character. These fall-breaking appliances are most frequently 

 composed of threads of first quality rubber, grouped together and 

 covered with a lace-work of cotton. The extremities are fitted 

 into attachments so constructed as to be fixed to the aeroplane. 

 These attachments are made in various lengths from 10 to 20 or 

 30 inches and in diameters from yi inch to 1^ inch. 



Of course, these fall-breaking appliances vary according to the 

 construction of the aeroplane and the mode of landing con- 

 templated. They consequently vary according to its weight and 

 should be designed for resisting considerable strains. 



Instead of employing a number of threads of rubber grouped 

 together (of uniform diameter) rubber cords of various diam- 

 eters, for instance, from Ys Xo Ys inch can be used. Some fall- 

 breaking appliances have the form of a bracelet or ring, composed 

 of braided threads of rubber, with a lacing of cotton underneath. 



Still another type of fall-breakers is constructed, composed of 

 rings of first quality rubber, grey or red, very elastic and full 

 of nerve, placed flat above the axle and fixed on two points 

 attached to the landing mechanism. The rings are usually 4 to 5 

 inches internal diameter, and 5 to 6 inches external diameter, 

 with a thickness of Ys to 1^ inch. Three rings are placed three 

 or more on each side, beside each other. 



It would seem as if fall-breakers of various kinds are destined 

 to be more and more employed, their usefulness being incontest- 

 able. Suitably placed they deaden concussions of all kinds, both 

 horizontal and vertical, thus permitting landing in very easy 

 conditions. 



For this purpose the use of rubber is the natural course, it 

 being very elastic and possessing marked properties of resistance. 

 It is, moreover, so light that it will always be preferred to 

 metallic springs, for mechanisms intended to diminish con- 

 cussions. 



AVIATION EQUIPMENT. 



Among the numerous objects composing the aviator's equip- 

 ment may be cited the rubber "combination," of black, grey or 

 brown vulcanized rubber, a garment in one piece and therefore 

 inconvenient for putting on and taking off. A similar costume 

 but in two pieces, consists of blouse and pants, the whole being 

 of vulcanized rubber in various colors. The aviator is often 

 provided with an elastic belt, composed of a band in two parts, 

 united by a fastening, to' which are attached elastic cords fixed 

 to the leather straps, adjustable as desired, attached to the aero- 

 plane. This belt makes the aviator of one piece with his seat. 

 He cannot be thrown out, while, by reason of the elasticity of 

 the belt, the concussion in the event of accident is considerably 

 deadened. The fastening is easily removed when the aviator 

 desires to leave the aeroplane. 



Aviation, in fact, presents numerous uses for rubber and the 

 manufacturers who will take the necessary steps to furnish really 

 practical specialties for that purpose, will find satisfactory outlets 

 in this new industry. 



NIW FRENCH BUBBER COMPANY. 



With a capital equalling $250,000, a company is being incor- 

 porated in Paris, under the style of the "Manufacture de Caout- 

 chouc — Etablissements Edeline." The company will continue the 

 operation of the Edeline plant, located at Puteaux, Seine. It 

 is expected to maintain and develop the old connections of that 

 influential firm, the new organization being considered likely 

 to occupy an important position in the French rubber industry. 



The company has been organized by M. Gustave Bouquillon, 

 who lately resigned his position as consulting engineer of the 

 Societe Industrielle des Telephones. He will bring to his new 

 post the fruit of his long experience, as well as new processes 

 for the manufacture of automobile tires, which are regarded as. 

 ensuring the immediate success of the new company. 



