THE PELTERIC MONOPLANE. An aeroplane which is attracting considerable atten tion at Paris is the invention of M. Robert Esnault-Pelterie, an aeronaut of great scientific ability as well as practical skill. For some time past M. Pelterie has been making a series of calculations and experi ments with small models, and recently he built the large full-sized aeroplane shown in the accompanying illustrations and made several short flights with it over the plain at Bue, a point not far from Versailles. The new flyer has a long cen tral body and a single trans verse plane, which gives it the general appearance of a butter fly. The plane is somewhat curved from its front to its rear edge. At the rear of the body is a flat plane used as a horizontal rudder, while the motor and propeller are placed at the front of the main body in advance of the single aero plane. Joined to the bottom part is a light frame carrying a pair of wheels for traveling upon the ground. The 25-30-horse-power air-cooled motor is built according to the invent or's designs and is of a some what unusual construction, having seven cylinders stag gered and arranged in a circle. It is of light weight, its total weight in running order being but 44 kilogrammes (97 pounds) which makes it weigh between 3 and 4 pounds per horse-power. The machine illustrated has a supporting surface in its single aeroplane of 18 square meters (193% square feet); but the reconstructed machine will have only 16 square me ters (172V4 square feet). The total weight of the flyer with operator is 240 kilogrammes (529.1 pounds), of which the motor and propeller make up 55 kilogrammes ( 121VL pounds), the rudder, wheels, and gasoline 10 kilogrammes (22 pounds) each, the aero plane 60 kilogrammes (132% pounds), the framework 20 kilogrammes (44 pounds), and the operator 75 kilogrammes (165 pounds). The new aeroplane was recently tried for the first time near Paris. The first trial was made at 2:20 P. M. on the after noon of October 22. After the aeronaut had seated himself in the machine, the motor was readily started, and the aeroplane was released. It ran along the ground lightly like a bird taking flight, the wheel on the end of one wing touching the ground gently as the machine tipped to one side. After running some 64 feet, the machine had attained a speed estimated at about 37 miles an hour. M. Pelterie operated the horizontal rudder, with the result that the aeroplane rose off the ground and made a flight of about 328 feet at a height of 5 or 6 feet. It dropped lightly to the ground and ran on its wheels for about 65 feet, after which it again rose in the air a few feet and, in a very graceful curve, described a semicircle hav ing a radius of about 1,640 feet. M. Pelterie then cut the ignition current, and the machine once more landed lightly without damage. At 2.40 P. M. a second trial was made. This time the machine was started in the high grass and on very uneven and rough turf. It again responded to its horizontal rudder, and rose in the air when going at full speed. This time it made a flight of about 492 feet, and rose to a height of from 20 to 25 feet. In stead of coming down gently and running along th ground, the machine suddenly dropped almost vertical ly. Although the shock of the fall was a severe one, the wheels, motor, propeller, etc., were not damaged; but the wooden framework and aluminium braces gave way, and one end of the -monoplane (which is made in two halves) was broke-.1. The inventor had two new planes ready, but as it was a matter of sev eral days to replace the broken half, no further flights were made on this particular day. The new machine is to have less sustaining surface, yet the inventor estimates it will leave the ground at a speed of 31 miles an hour instead of 37. The width of the plane will be 8.6 meters (28.21 feet) instead of 9.6 meters (31.49 feet). The Pelterie aeroplane resembles the monoplane machine with which M. Bleriot experiment ed unsuccessfully last spring. The machine is mount ed on but two wheels placed in the same vertical plane beneath the center of the body. The idea of having wheels on the ends of the plane appears to be new, and it seems to have worked out well in practice. FARMAN'S RECORD FLIGHTS. M. Henri Farman, who has been carrying on a series of experiments with his new aeroplane at the drill grounds of Issy, near Paris, recently had a bril liant success, and in a flight made on the 26th of October he covered a distance of no less than 2,529% feet. The delegates of the Aero Club were present on this occasion, with the official timekeepers, so that the result is registered in due form and thus consti tutes the world's record for an aeroplane flight. Such a performance is most encouraging in the present state of aeroplane work. Hitherto Santos Dumont held the record for the longest flight, and the record of 22 meters (721 feet), covered in 211/5 seconds, which he made as far back as November 12, 1906, had hither to not been surpassed, in spite of the efforts made by the numerous experimenters in the field. We have already given a description of M. Farman's aeroplane, with some of the principal data, referring also to a flight of 285 meters (935 feet) which he made not long since; but as this was not officially observed, it could not be taken as a record, although it already exceeded Santos Dumont's flight. During several days after this. M. Farman made a nr iiber of flights, cover ing distances of 300 to 600 feet. In these flights the aeroplane showed a remarkable stability and it was well under control, keeping at different heights above the ground of between 12 and 18 feet. It alighted without any difficulty, thus demonstrating its staunch construction. Most of these distances were officially observed, and some of the flights were carried out in the presence of Grand Duke Leopold-Salvator, of Austria, as well as M Archdeacon, Capt. Ferber, Louis Bleriot, and oth ers. On the 26th of October, M. Farman commenced the se ries of flights which ended in establishing his present record. In the morning he made four successive flights in very good condition, these being 120 me ters (393.7 feet) at 3 meters (9.84 feet) height; 85 meters (278.87 feet) at 4 meters (13.12 feet) height; 112 meters (367.45 feet) at 3 meters height; and 180 meters (590.55 feet) at between 4 and 5 me ters height. At 11 o'clock he made a fine start and suc ceeded in covering 363 meters (1,190.94 'feet) in a straight flight, and recommencing the experiments in the afternoon he started at 2 o'clock and made a flight of 403 meters (1,322.17 feet). After this the Aviation Commission of the Aero Club was convoked upon the grounds. At 4 o'clock he succeeded in covering 350 me ters (1,148.29 feet) at 3.5 me ters (11.5 feet) height in 27 seconds, measured by Messrs. Peyrey and Voisin, with the time taken by M. Archdeacon. In the final flight he steered diagonally across the drill grounds, keeping a height of 6 meters ( 19.6 feet) and cover ing a distance of 771 meters (2,529.52 feet). He stopped at thirty feet from the inclosing wall by a skillful maneuver, and were it not for this ob stacle he could have gone far ther. A great crowd was as sembled on this occasion, and much enthusiasm was mani fested at this remarkable re 359 suit. M. Farman wishes to continue his experiments so as to try to solve the difficult problem of steering in a curved line, and as he has the flyer under good control we may expect some interesting results. Should he be successful, he will make an entry at the Aero Club to compete for the Grand Aviation Prix for one kilometer (0.621 mile) in a closed circuit, which is offered by Messrs. Deutsch and Archdeacon. His machine is apparently capable of winning the SCIEN TIFIC AMERICAN Trophy, as it has already covered three-fourths of the distance required to be made by the first winner. One of our illustrations shows Far-man's aeroplane in flight. In connection with the above description of M. Far-man's recent flights, the appended letter from him to the editor of "The Car" may be found of interest to our readers: "The machine on which the recent trials were car ried out is of the cubic type; that is to say, it is formed of two linen cubes, a large one at the front being 12 meters in length, 2 meters in width, and 2 meters in height, the other smaller at the rear, attached to the first by means of wood rods. A point-shaped car finishes this machine and holds the motor, the tanks, the driver's seat, and the operating appa ratus of the motor. The equilibrator is placed at the front of the car, and the rudder at the back. "To leave the ground is still not an easy matter, but to fly is still much more difficult. I succeeded in leaving the ground every day during the last two months, but it is only quite recently that I managed to make a flight of a distance of 285 meters, thus beat ing M. Santos Dumortt's record. Unfortunately, this flight was not controlled by the necessary officials, but this is only of slight importance, as I am absolutely convinced that I shall succeed in making most inter esting flights. "Up to the present all flying machines constructed lacked stability. At every experiment they were smashed in landing; whereas I am glad to say that notwithstanding my several flights, varying between 100 to 2S5 meters, nothing in my apparatus broke or gave way; besides, it stands absolutely horizontal. "However, I am up*'ble for the moment to fly more than 600 or 700 meters; for once in the air, one of the two following things happens: I rise too high, and my present motor is not sufficiently powerful to produce the work necessary to lift the apparatus, weighing 500 kilogrammes, to between 5 and 10 meters, or else a wrong movement is given to the equilibrator, which brings me back to the ground. This can be remedied once I have my machine well in hand, and after more practice. One important point is the regulation of the motor, which will render it more efficient, so as to compensate the errors in the driving of the machine which are unavoidable at the beginning. "As an indication of the difficult nature of the work, the following are the different parts which I have to survey and handle for the driving of my apparatus: The rudder at the rear, the equilibrator, the advanced ignition, the carbureting handle, manometer for water pressure. Moreover, I have to move from right to left according to the direction taken by the machine. I have also to keep the machine face to the wind. The crowd usually present also calls my attention, and my movements are somewhat impeded. I must also observe the motor explosions, as the least irregularity in these would bring me immediately back to the ground. All this is very difficult and complicated, but with practice and skill I am sure to succeed. "My hopes are unlimited, and I expect to be able one day to travel at a rate of 100 kilometers per hour with a flying machin' ; for I am convinced that the aviation problem is solved in principle, and that in the near future progress will be such that a journey at a rate of 100 kilometers per hour will be just as possible in the air as on the road. For the moment, I limit my ambitions to the accomplishment in a few months of a flight of a kilometer." On November 7 M. Farman twice beat his best pre vious record of 771 meters. The longest measured flight on this date was 800 meters (2,624.66 feet). In a subsequent flight during the same afternoon his ma chine is said to have covered fully 100 meters more, or a total distance of 900 meters (2,952% feet) in 70 seconds. In this flight the machine made a double turn in the shape of the letter S, and accomplished this maneuver with excellent stability. THE BREGUET GYROPLANE. Up to the present, most of the flying machines which have been brought out by leading aeronauts, on the Continent, at least, have been of the aeroplane type. Another type is the combination of a small dirigible balloon and one or two aeroplanes placed beneath it. This arrangement is also heavier than air and is made to soar by the action of the planes. There have been but few machines of the flapping-wing type con structed as yet. Still anothei form of flyer, and one which is of great interest, is the helicopter, in which the lifting action is brought about by two horizontal propellers revolving in opposite directions. Up to the present, inventors do not seem to have had much suc cess with this form of machine, but recently a new flyer has been brought out in France which is to use the helicopter principle. It is at present in the first stages of experiment, but the inventors have already demonstrated that it has ample lifting power to rise in the air vertically and at the same time to lift a man. It now remains to adapt a propelling mechan ism to the flyer in order to make it travel horizontally, and this the inventors propose to do in the next stage of the experiment. The new flyer, which is shown in our illustrations, was built at Roubaix in the Br guet establishment, under the direction of Messrs. Louis and Charles Br guet and Prof. Richet. It differs essentially from what has been constructed up to the present, both as to the ideas involved and also in the execution. In this case the lifting action is obtained by the reaction upon the air obtained from four gyratory systems, each of which consists of eight revolving aeroplanes. A motor placed in the center of the apparatus is con nected, through horizontal shafts and bevel gears, to the four vertical shafts of the revolving aeroplanes, and these are all driven at the same time. Each of the gyratory systems consists of an upper and a lower horizontal rod mounted on a vertical tubular shaft and connected together by vertical braces. At the outer ends of the rods are mounted small aero planes which give the whole the appearance of super posed four-bladed propellers of large diameter (26% feet). The inventors claim that on account of their special arrangement they utilize the gyroscopic action of the revolving aeroplanes, which, they claim further, gives the machine perfect automatic stability in the air. At any rate, the application of the gyroscope principle to an aeroplane is of interest and may lead to some very practical results. For this reason the inventors give the name "gyroplane" to the present apparatus. As to the mechanical design of the new helicopter, the present apparatus is merely a first experimental form made in order to demonstrate the lifting power. The main frame of steel tubes which carries the whole is built in the form of a St. Andrew's cross. In the middle part is mounted the gasoline motor, which is of the extra light-weight, eight-cylinder, V-type, capa ble of developing a maximum of 45-horse-power. The aeronaut's seat is placed below the motor, and above it is located the gasoline tank. At the four ends of the long horizontal tubes that extend out from the motor are placed four vertical shafts fitted with castors at their lower ends and carrying tubular sleeves to which are secured the horizontal rods of the eight aeroplanes. The use of twin planes is said to give a better equi librium in the air. There are thirty-two surfaces divided into four sets and giving a total area for the flyer of 26 square meters (280 square feet). They are driven at a speed of 48 revolutions per minute, and describe a circle of 8.1 meters diameter (26% feet), corresponding to a speed of 26.4 meters (86% feet) per second at the center of action. The total weight of the flyer when mounted by an aeronaut representing 70 kilogrammes (154 pounds) is 540 kilo grammes (1,190 pounds). The motor weighs 170 kilo grammes (374 pounds) in this case. In the trials of the lifting power it was found that at the above speed of the planes the apparatus could rise in the air and keep itself off the ground at a height of a few feet, but as it was not equipped with steering devices it was considered unwise to make any more than a demonstration of the lifting power, and therefore the helicopter was.held by hand so as to prevent it from rising higher. When the motor was slowed down, the machine settled down on the ground very easily and without shocks. To avoid any accident from a false maneuver, the lifting test was limited to one minute, but there is no doubt that it could keep in the air for a long time under the same conditions. The inventors have thus proved the value of their theories as to the gyroplane in a striking manner, in view of the fact that they were able to raise and hold a weight of 1,169 pounds in the air. Supposing the motor to have developed 40 horse-power at 1,380 R. P. M. (the speed at which it ran), it will then be seen that the gyro plane lifted 29.2 pounds per horse-power. In reality, however, it probably did even better than this, which shows that the new arrangement is rather efficient despite its cumbrousness. The area and curves of the aeroplanes were deter mined from the following formulas: R — the vertical reaction obtained by the system of revolving aeroplanes. ? — the number of revolutions per second of these systems. D — the diameter of the circles described at the periphery of these same systems. W — the power absorbed in kilogrammeter-seconds to drive these systems, including the transmission losses. P = the weight of a complete system of revolving aeroplanes. From these symbols we have the following rela tions: = 0.017 n2D4. W = 0.0075 n3D\ P = 0.6D2. It should be noted that on account of the method of construction employed, the weight of the machine increases only as the square of the diameter instead of as the cube, which was the relation found by Col. Renard, and as a result of which he found it practi cally impossible to build a helicopter with sufficiently large propellers to lift a man and a motor.
This article was originally published with the title "The Latest French Aeroplanes and Their Records" in Scientific American 97, 20, 358-359 (November 1907)