A Soaring Machine.
An instrument for making scientific experiments
Designed by James Means.
To any one who desires to take up this most fascinating study, [Figs. 3 and 4] will give a general idea as to the construction of his first instrument for making experiments. A represents a backbone five-eighths of an inch square and four feet long, made of pine wood; B, the main aeroplane, eight inches wide and three feet long. This should be made of light tin plate, and bent in the middle so as to form a flattened V; the angle should be about one hundred and seventy degrees. C represents a steering aeroplane six inches by twenty-four inches, pivoted at cc, also made of light tin plate; D, a vertical aeroplane four inches by twenty inches, rigidly fixed in the wooden backbone; E, a rod of steel wire, eighteen or twenty inches long, and carrying an adjustable leaden weight of three ounces; K, a rod two and one-half inches long, soldered in the centre of and vertical to the plane C, with a pivot at the upper end with which the rod MM is connected. This rod should have five or six pivot-holes at its forward end N, so that its working length may be varied for different experiments; J, a rod pivoted at G, free to swing fore and aft; N, a pivot where the rod MM joins the rod J; F, a leaden weight adjustable higher or lower upon the rod J; its proper weight is x, an unknown quantity. Upon ascertaining by repeated experiment the right weight for F, the right position for the adjustable weight E, and the right length for the rod MM, the reaching of the maximum efficiency of a system of aeroplanes largely depends. I think that this sets forth with clearness the problem as it stands to-day. When it is fully solved—and it certainly seems solvable—right and left steering will be a less difficult matter, and alighting will be accomplished by killing the momentum when near the ground by an abrupt upward slant of the main aeroplanes; but this is an anticipation and a digression. Now to return to the instrument we are considering: this soaring machine is intended to gain velocity by a swoop, and then automatically steer itself into a horizontal or very slightly descending course, as indicated by B and C in [Fig. 2]. It depends upon the principle that the pendulum rod always seeks the perpendicular; for instance, when the machine is launched pointing steeply downward, the positions of the pendulum and aeroplanes are as shown in [Fig. 5]; therefore the steering aeroplane C will, as soon as velocity is gained, lay a strong hold upon the wind of flight, and have a tendency to bring the machine into a horizontal course. Now, if the length of the rod MM is made correct by adjustment at the pivot-holes near N, when the desired course, a very gentle decline, is reached, both aeroplanes will be approximately horizontal, as shown in [Fig. 6]. If, however, the machine deviates either upward or downward from its intended course, the weight at the end of the pendulum causes the steering aeroplane to correct the error. [Fig. 7] shows the effect of a slight upward deviation.
