Newspaper Page Text
NEW YORK-CHICAGO PLIGHT.
HOW AN AEROPLANE WORKS, AS SHOWN BY GLENN GURTISS A Simple Explanation of Flight in Un technical Terms For the Average Man. The aeroplane of Glenn II. Curtlss, In which he made his Albany-NVw York flight, Is the one from which the accompanying diagrams nre drawn. The Curtlss machine is held to have proved Itself, by the recent HUht, the most advanced type of aeroplane yet devised in, America, possibly In the world. The Curtlss aeroplane is shown In ground plan in Figure 1. The aero plane flics in the directum Indicated by the arrows. A Is the altitude rud der, perched out at the end of a bam boo framework, In front of the driver. A I . hi i' i Tliiilllllllpiilli mmf MM ;nGri.-GRDurib plan li B, are the two stabilizing rudders, out at the ends of tho planes. C is the rudder for lateral steering, perched out behind, as A Is before. P P Is the upper sustaining plane, four feet under which lies the lower sustaining plane, parallel and of the same shape and size. In front of the experience, exists us in the aeroplane planes Is the steering wheel, Just of to-day, rude and imperfect, corn back of V is the nernplanist's peat, S, pared to Its prospects, as it still pre and between the planes Is placed the ' snmably is. And the freedom and B; B t I y big engine. Hack of the engine and behind the big planes Is the pro peller, X. In the type of aeroplane now most developed, the propeller, X, placed be hind the engine, E, and the driver, at S, forces tho lnauhine forward In a horizontal direction. The planes, P, P, catch tho air on their under sur faces, slightly inclined and concaved for that pi'rpos". Tho pressure lifts the machine In the air or sustains it there at a desired level. The engine that, supplies the power Is a gasoleno explosion motor closely similar to that used In automobiles. Only slight differences are necessi tated by the adapting ot the engine to the aeroplane. The controls for the magneto and gasolene supply are placed forward of the engine, at the driver's seat, S, for be is under the disadvantage of sitting In front of the motor. It. is now to be seen how the pro peller, X, driven by tho engine, E, Bends forward tho machine, which is sustained by the gliding on the air of tho plane, P P, and the similar plane under it. There remains to be seen the more delicate aud difficult part of j J! . V j, (PROPgllEft t FIG5.VIEWlOFiTHE"AEROPLA flying, namely tlip work of keeping the flyer straight und level. Each of the rudders, A, R 11 and C, dees its own particular share of this work. It is a threefold work, and far more complicated than the control of auto mobile, ship or bicycle. All these travel on a horizontal surface and are guided only to right find left. The function of the forward rud der, A, Is to turn the course of the aeroplane up or down. Right here .ho tremendous difference between the neroplnnc nnd almost all methods of locomotion known to us becomes of curtiss'aeromane; apparent. To realize the difference, It is only necessary to try to conceive an automobile that one could, by a turn of the wrist, start to soaring up ward from the ground. Nothing elso so free and complete in the whole realm of motion, as known to human FIG.' 3.FR0NTi VIEWOE STABILIZING VPLANES,IB.8. complete command of space that dis tinguish the aeroplane all lie in rud der A, the altitude rudder. Figure 2 is a drawing ot the essen. tlal details of this wonderful rudder. The rudder is shown from a point of observation forward of it and to its left. The rudder consists of two hori zontal planes, p p. They are con nected with a framework similar in shape, to the skeleton of an oblong box. This framework has the planes p p for its top and bottom sides. The framework hinges at the two ends on the axis represented by the dotted line, a. It Is by turning on this binge that tie planes are made to act as rudders. This action is produced In the fol lowing manner: When the frame work is tilted so that the fronts ot the planes point upward, the air through which the aeroplane is ad vancing catches on their under side. The pressure of the air on the under sides of the planes lifts them up, and so lifts the nose of the whole aero plane up, making it take an upward direction. When, on the other hand, tho THE TWO MOST planes p p are tilted downward, the air as it is cleft presses on their top surfaces and forces them to point earthward. And so they give the downward direction to the course of the aeroplane, when the flyer desires to fly lower. It will readily be seen that without the altitude rudder, A, the aeroplane would bo helpless. How is the altitude rudder con trolled by the areoplanlst? The view in Fig. 2 shows this in the ap paratus, c c c. This Is a peculiar but perfectly simple device. The rudder is pushed forward or pulled back by a long rod. The rod runs from a erosspiece of the framework of the rudder back to the steering wheel. It Is fastened at tho hub of the wheel. The wheel works backward and for ward as well as turning. More vital still than the altitude rudder, and certainly more of a de parture from all other known meth ods of equilibrium, are the stabilizing rudders or fins, 13 B. The w orking of these is shown in Fig. 3. An aeroplane Is poised as delicate ly on its airy even keel hb a tightrope walker on bis wire. The stabilizing fins serve the same purpose as do the fan of the Japanese tightrope per former. They save the flyer from tip ping over to one side or the other. Fig. 3 will show bow this is done. The purpose of the arrangement hei; shown is to to tilt the one plane up ward and the opplslte ono downward at the same time. The control of the planes, B B, lies In the wires c c c c. The nxls of each plane lies in the dotted line, A. The wires, cc, fastened behind the axes of the planes, tilt them by an upward or downward pull. The wires e c run down from each plane to a pulley at the corner of the lower sustaining plane, P. From the pulley they run straight to the top of the back of the driver's seat, S. There they are fastened. When it Bways to the right, it pulls the wire that draws down the rear of the stabilizing plane out at the left wing tip. When the seat sways to the left, it draws down the stabilizing plane at the right wing tip. The wring, c c, runs also up from the tops of the stabilizing planes through pulleys overhead, and so con. nects the stabilizing planes from above. When, therefore, one stabilize ing plane has its after edge pulled down by the tilting of the seat back, tho same pull, communicated by the wire overhead to the other stabilizing plane, pulls Its rear up. Whichever way the one stabilizing plane is turned, the other one is turned oppo sitely. The manner In which this action rights the aeroplane will be readily understood. The process is as fol lows: As soon as, in the course ot flight, the aeroplane sags to the left, the driver leans over to the right la his seat. It is the motion that be would naturally make to find his own equilibrium. In leaning to the right he pushes the seat back over with him. This pulls the wire that draws down the left stabilizing fin's after part. Thus the fin turns on Its axis, or In such a way as to present a slant Ing under surface to the wind. The wind delivers an upward pressure on this surface, and this upward pressure tends to right the sagging left end of the aeroplane. At the same tiue the pull that started from the seat back FEASIBLE ROUTES FOR THE AIRSHIP RACE. is sent on from the left fin over the overhead wire and down to tho upper surface of the right fln, which is drawn up. The right fln Is thus made to present Its upper surface to the wind, and the wind then depresses the right end of the aeroplane at the same time that the left is being raised. In a moment the aeroplane is righted. The driver thereupon straightens up in his seat, bringing the seat back again to the upright position and so drawing the stabiliz ing fins back again to their original place. The third of tho important con trols of the aeroplane in the air is thown in Fig. 4. It is the Bide to side steering gear, the most complicated, "ft- FIG.2.-ELEVATI0N OF. because it is the least important. It needs a second motion of the hands, which are already busy with the alti tude control. Fig. 4 shows a view ot the slde-to-side rudder, C. It is cleft, and through this cieft passes a horizontal plane. This is just a fixed plane, placed to sustain the weight of the after end cf the aeroplane. The rud der C, save for this cleavage into an upper and a lower part, is very sim ilar to a ship's rudder. It Is note worthy that this is the only vertical plane on the whole Curtlss machine. The rudder C swings on a vertical axis, a. The positions into which it may swing are shown by the dotted lines. It is with this wheel, ot course, that the driver turns to right nnd left, doubles on his course and makes the most complicated evolutions. There are other things that the aviator has to ottend to besides his direction and stability control, of course. But they do not require his ever taking more than one hand from the steering wheel. There is the throttle which feeds the fuel to his engine. It is a short, slender lever, at his right hand. A brief motion cuts off his fuel and shuts down his engine, or lessens his speed or in creases It. The electric control is In a little twist-button fastened on the front of his seat between his knees. In starting, Curtlss, after testing his engine, first takes his place In the driver's seat, turns on the throttle and grasps the steering wheel. Then, while two or three men hold the ma chine from darting forward on its wheels, a mechanic starts tho engine with a quick turn of the propeller. With the propeller going briskly, Cur- t:FIG;4.ELEVATI0N OF. tiss gives a Blgnal, and the aeroplane is released by the men holding it. It starts forward rapidly on its wheels. When the right Bpeed is reached, Cur tlss pulla the steering gear back a little toward him. The aeroplane rises from the ground. The ground friction overcome, it gains speed rap Idly and rises faster, till It reaches the desired level. In descending, Curtlss picks out with his eye the favorable spot. When within some 200 yards ot it and at some twenty yards' elevation, he shuts oft his engine with a move ment of the right hand. Depressing the head of his flyer, he glides down mentum. Condensed From the New York Evening Sun. 2 The Value of an Eye- S Witness. 2 The experiment tried by Professor McKeever, of the Kansas State Agri cultural College, as to the reliability of the average witness is but the rep etition of other tests upon a more ex tended Bcale and directed toward th same end. The results also were sim ilar, and they help to Batisfy us that the evidence of the ordinary eye-wit-nesB has a very Blight value and that there are few among us who can de scribe accurately even the simphj events that transpire In full sight, AI) VTUDE'RUDDERT A.vi Professor McKeever went to soma trouble in his experiment, which was arranged in imitation of an actual crime. He drilled three ot his stu dents to perform a "hold up," and the little drama was enacted upon a stage in front of the class. A subse quent examination of the audience disclosed the fact that It was at sixes and sevens as to what had actually happened. The students were unable to agree as to which of the "robbers" hnd carried a revolver or worn a rain coat, and all the other facts were sim ilarly obscure. Any ono of the wit nesses could have given an account of what he believed he bad seen, and no doubt by Itself It would have pnssei as good evidence, but unfor tunately the student who sat next to him believed hiriself to have seen something quite different. Professor Munsterberg recently car ried out a whole series of experi ments directed toward the same end, and the result was even more remark able. He used for the purpose a large class of Btudents whose powers of correct observation ought to be above rather than below the average. He tested them In a great many ways, requiring them to estimate the cum ber of colored spots upon a sheet ot white paper, the numberof persons in a room, and the length of a pendu lum stroke. The results showed not only an extraordinary Incapacity to observe correctly, but a still more ex traordinary difference in the kind of Incapacity, inasmuch as the estimate of one Btudent would be ludicrously too high, while that of the man next to him would be ludicrously too low. It is evident that we must revise our opinion as to the value of eye witness evidence. Its value seems to SIDE TOPSIDE RUDDER. (3 be very slight, even with the best of Intentions, and we may yet find it necessary to subject our legal wit nesses to tome kind of test before al lowing them to testify as to what they have seen. They may be incap able of seeing anything with accu racy. San Francisco Argonant. Truthful Bobby. Mother (reprovingly) "Bobby, t told you distinctly if Mrs. Jones asked you to have a second piece of cake, to say 'No, thank you.' " Bobby "I know, ma, but saa didn't say wouU I 'have,' she al4 would I 'like' another piece, and It I'd said 'No,' I'd er told a lie." Bo ton Transcript.