CHAPTER V. Remarks.

In a little booklet such as this it is even impossible to cover the subject of gliding flight fully much less power driven aeroplanes, but a short description of such a machine built by the author, assisted by Mr. Harold Dodd and Mr. Safford Adams will no doubt interest many since it has been used successfully as a glider in towed flights.

The machine was attached to an automobile by means of a long piano wire bridle. It rises at a speed of between 15 and 20 miles per hour and remains in the air as long as the auto keeps moving at this rate. The grounds used by the author in his experiments limited the flights to about 800 feet.

The automobile in one flight traveled about 50 miles per hour, but the machine soared on a perfectly even keel and without any pitching. Just as the author was about to descend, the towing wire broke, but the aeroplane glided so gently to the ground that it was impossible to tell where it first touched.

The following description of the machine is an extract from an article written by Mr. R. S. Brown.

"The two supporting surfaces of the aeroplane are five feet wide in the direction of flight and twenty six feet long. When the machine is moved rapidly forward, the action and reaction of the still air on the lower side of the moving surfaces, lifts the aeroplane from the ground and supports it in the air. The curvature of the planes is that segment of a parabola, whose depth is one ninth its length. They are spaced one vertically above the other and about four and one half feet apart in the middle. The ends converge slightly to make the machine less affected by cross gusts. The longitudinal curvature of the planes is maintained by spruce ribs half an inch square and spaced nine inches apart. Their front ends are ingeniously fastened in brass sockets on the front horizontal members and their rear ends project about a foot over the rear horizontal pieces. The fabric a close woven muslin is put on over the top and bottom of the ribs and is fastened by grommets to a wire running through the rear ends of the ribs, and by strips of felt fastened down to the ribs with upholsterer’s tacks.

"The stanchions are six feet apart except the middle two, which are only eighteen inches apart. The horizontal pieces of each surface are parallel and four feet distant from each other. All are of selected spruce, shaped so as to give the greatest strength with the least resistance to the air, and the least weight. All the many rectangles of the structure are braced diagonally with steel piano wire. In every one a small turnbuckle is inserted to adjust the length. The nuclei of these turnbuckles consists of bicycle spokes. By this wiring a perfectly rigid truss is formed.

"Ten feet to the rear of the main body, there is a horizontal tail, which halves a vertical rudder of about the same area. This vertical surface is movable and turns the aeroplane to the right and left when moved by rotation of the steering wheel. As can be seen in the accompanying illustration these rudders are strongly supported from the principal structure.

"At an equal distance in front of the supporting planes is the elevation rudder. This consists of two horizontal plane surfaces, six feet by two. These turn about a horizontal axis transverse to the direction of flight. Thus the angle which they present to the wind can be altered at the will of the operator. This is accomplished by pushing and pulling on the steering wheel. Through the middle of the horizontal surface runs a triangular vertical plane. This is designed to prevent the turning of the machine by a gust striking the rear vertical rudder, for if it strikes both vertical surfaces, one in front and one behind, the two neutralize each other and no turning takes place.

"On the ground the machine runs on three twenty-inch pneumatic tired wheels. These were especially made for the purpose, with seamless rims and heavy motorcycle spokes. Two are set in regular forks of tubing under the rear edge of the lower plane, while the third wheel is considerably in advance of the body proper. When running on the ground preparatory to rising, the machine is carried on these little wheels.

"The operators seat is in front of the supporting planes, and as the photograph shows is carried on two braces from the front wheel. Sitting in the seat, the aviator can direct the aeroplane from side to side by turning the steering wheel before him. This steering wheel is mounted on a post hinged at the bottom, and by pushing or pulling on the wheel the aviator is enabled to control his height above ground by means of the elevation rudder which is connected by a wooden rod to the steering post.

"Mid-way between the two main surfaces and at the front of each end is a small plane. These are tilted at positive and negative angles to the wind, by means of cords connecting them with a pivoted bar moved by the pilots feet. In flight, if one end rises, the aviator presses down the end of the bar on the rising side. This causes the ’balancing plane’ on the high side, which is the name given to the movable planes just described, to form a negative angle with the wind so that the high side is forced down. The other balancing plane assumes an equal positive angle, so as to force up the lower side. Thus the machine is again brought to an even keel. After a little experience, this action becomes almost automatic, so that no difficulty is experienced in keeping the flyer level.

"The motor, which at present has not been installed, will be supported between the two main planes and connected to a laminated spruce propeller, six feet in diameter.”

Those who of until late have not been associated with aeronautics can scarcely realize the steps by which aviation had progressed and the trend towards building machines.

The aeroplane worker can no longer be classified with the seeker after perpetual motion. It is therefore to be lamented that so many of these machines partake of freak construction. Originality is always to be fostered but must bear some degree of proportion.

Only a very few favored people in comparison to the rest of civilization have been enabled to see an aeroplane in flight. Many times less are those who have had the privilege of examining a successful machine.

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