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Aviation History
1914
1914 - 0820.PDF
^m\ CORRESPONDENCE:. Brakes for Aeroplanes. 1880] I have read the correspondence in FLIGHT on the above subject, and, if I understand correctly, it is only suggested to apply a brake after the aeroplane has alighted. Would it not be better to use a brake which can be applied before the machine alights, and thus land in greater safety ? Most people would answer " Yes, but as the speed is reduced the machine would fall more rapidly." As many of your readers are aware, I have been conducting experiments for some years with the object of including as many " desirables" as possible in one simple device, so, with your permission, I will give the net result of these experiments up to the present. The following is a design of a combined propeller, lifter, brake, steerer and stabiliser : The upper figure represents an end elevation of a propeller of the paddle-wheel type, revolving in the direction of the arrow, C, On a stationary crank shaft, L, having feathering planes, BJ to B4, worked by means of connecting rods, D, one end being attached to said planes and the other end to crank, E, the planes, B1 to B4, being pivotally attached to the arms A1 to A4. The dotted curves, M, show the position of the planes, B' to B4, at various points in a revolution. The machine is travelling in the direction of the arrow, F. Here are two chief peculiarities in this design. 1. It revolves in the opposite direction to that of an ordinary paddle-wheel. 2. The hollow surface of the blades or planes is on the outer side. As a propeller, the thrust is largely obtained from A-1 to A2, a very rapid movement of the near edge G of plane taking place within that quarter revolution. Compare the angle made with plane B;i and arm A3, with that made by plane B- and arm A2. As a lifter, the hollow surface of plane presses down on the air from As to A1. Further, a carnage wheel travels horizontally at three different speeds at the same time, viz., the centre travels at the same speed as the carriage j the point touching the ground does not travel at all; and the point opposite, i.e. the top of the wheel, travels horizontally at double the speed of the carriage. Now apply this law to the above design. If there were no " slip," A* would be stationary in the air and A1 would be travelling forward at double the speed of the aeroplane. With what result ? Either an enormous increase in the lift, or the capacity of flying more slowly on account of the increased lift. But as there would be some " slip," A1 would be travelling forward at more than double the speed of the aeroplane and the lift still further increased. In a coarse pitch propeller the hollow surface of plane would be as at M', the others remaining practically unchanged. On this and another point I had a stiff argument with the late S. F. Cody at the Olympia Aero Show of 1913, and who remarked after some discussion, " I don't see it, but if I do I'll give way." I was able to demonstrate my points by means of a model, and, like a good sportsman, he gave way. To use the device as a brake, it is only necessary to partially revolve the crank shaft, L, in the direction of the arrow, C. If the reader will turn the design 45" in that direction, so that N is at the top and NM at the bottom, it will show him the relative positions of the planes Bl to B4 and M when the crank shaft L has revolved 45°. The aeroplane is still travelling in a horizontal direction, viz. O to P, but he will observe that the plane at NM forms a greater angle of incidence than at B1 when A1 to A3 is vertical, and of course gives greater lift and helps to support the machine when the flying speed is reduced. If the reader will turn the design still further until As and A4 are vertical, he will notice that the plane Bs (which is now at the bottom) has a still greater angle of incidence and the lift is double what it ® ® Flying Over Monte Rosa. DURING a trip from Novara in Italy to Viege, Valais, Switzer land, on the 26th inst., the Italian pilot Landini on a Gabardini monoplane flew over Monte Rosa in the Pennine Alps, the highest point of which is 15,217 ft. He flew by way of the Nordengrat, the Gornergrat, the Findelen Glacier, and then along the Zermatt valley. He was accompanied by Dr. Giuseppe Lampugnani. It is claimed that during the flight Landini beat the Italian height record for pilot and one passenger with 3,450 metres. The old record to the credit of Pettazzi was 3,275 metres. New Italian Height Record. ON the 27th inst. at Milan, the Italian pilot Desbrueres on a Gabardini monoplane succeeded in improving on the Italian height record by going up to 4,950 metres. The previous record was 4,700 metres made by Lieut. Salome. JULY 31, 1914. was when B1 was at the bottom. The machine is still travelling horizontally, viz. from A8 to A1, and the brake may be considered " hard on," or nearly so. If we turn the design still further (which is equivalent to the pilot partially revolving the crank shaft L), the machine would run backwards when the planes at any point from B9 to B3 are at the bottom, assuming the machine to have alighted. This gives the same result (but with safety) as reversing the thrust of a screw propeller by reversing the engine, which I should consider most dangerous. Is it not a fact that in order to overcome the torque of a screw propeller, the engine and propeller are fixed slightly on one side of the lateral centre of gravity ? If so, and the engine is reversed, which means the torque of propeller is reversed, what is going to prevent the machine from capsizing laterally ? In order to steer with this propeller, two would be fixed on a machine, one on either side of the fuselage, and just as an oarsman A3 \M may backwater with one oar and stefer to right or left, so by converting only one propeller into a brake, an aeroplane may be steered. To obtain lateral stability, divert the thrust of one propeller up and the other down at!the same moment to counteract any tendency to capsize laterally. The lower figure shows a back view of plane B1. These details have not previously appeared in FLIGHT or any other journal devoted to aeronautics, and for lack of them a rather peculiar incident occurred at this year's Aero Show at Olympia. I attended most of the lectures arranged bythe Aeronautical Society, and at one of them, on " How an Aeroplane is Propelled," I heard my invention quoted and wrongly described. It was not the lecturer's fault, for, in conversation with him afterwards, he told me he had taken it from an old copy of FLIGHT (March 18th, 1911). These particulars were as supplied by me, but it was then in its early experimental stage. I note you are frequently advising modellists to make experiments of a more scientific nature ; if they care to try this device on their models, they may obtain permission by asking. The No. of my English patent is 16402 of 1912. JOSEPH CLARKSON. Prestwich Park, near Manchester. ® ® A Fatality at Juvisy. LIEUT. VALENSI, of the French Navy, was killed on Monday through a fall from a height of 500 ft. when flying at Juvisy. Renaux Crosses the Channel. WITH Mdme. Renaux as passenger on board his Maurice Farman, M. Renaux on the 23rd inst. flew from Hendon to Beau- marais, close to Calais. After a short rest he flew across to Hardelot. From Paris Across Bavaria. ON a Voisin biplane fitted with a 130 h.p. Salmson-Canton- Unne engine, Laporte, on the 22nd inst., set out from Villacoublay to fly to Bucharest and Constantinople with a view to securing the Coupe Pommery and the Prince Bibesco prize, &c. He was, how ever, brought down by a storm at Osterhofen on the Austro- Bavarian frontier, and in landing the propeller was smashed. The distance covered was about 850 kiloms. The machine carried a passenger, M. Sauval, as well as 450 kilogs. of fuel, &c. 820
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