23,347. Holle, A. A. Nov. 2. [Cognate Application No. 1803, A. D. 1909, dated Jan. 25.] Aerial machines without aerostats; aeroplanes ; steering and balancing. - In a device for automatically maintaining the stability of aeroplane machines, two side planes A, A<1> and a rear plane B are provided, and are so interconnected by cords that an upward movement of the tip of one side plane, say the plane A, produces (1) a downward motion of the front edge of that plane, (2) a downward motion of the tip and an upward motion of the front edge of the opposite side plane A<1>, (3) a downward motion of the right-hand tip and an upward motion of the left-hand tip of the rear plane B. Provision may be made to prevent the tips of the rear plane from moving upwardly, and the planes may be moved manually for steering. The side planes A, A<1> are curved longitudinally and transversely and are pivoted on a universal joint at a, a' to the frame of the machine. The rear plane B is secured at its forward edge b to the machine. The tips a<2>, a<3> of the planes A, A<1> are connected by cords a<4>, a<5> passing over fixed pulleys x. The forward edge a<6> of the wing A is connected by guided cords a<7>, a<8>to the tip a<2> of the wing, and by the cords b<3>, b<4> to the opposite tip b<2> of the rear plane. The cord b<3> may be provided with an adjustable spring c. The forward edge a<9> of the plane A' is similarly connected to the tip a<3>, and to the tip b<1> of the plane B. Instead of connecting the tips b<1>, b<2> to the planes at the points a<6>, a<9> they may be connected directly to the tips a', a<3>. In the form shown, the tips of the plane B are prevented by stops d from moving upwardly, the cords b<3>, b<5> having springs c to permit this. One or other of the tips of the rear plane can be depressed by cords c<1>, c<2> passing round a drum on the operating-handle C so that the movements of the planes can be made manually. Springs c are introduced into the cords c<1>, c<2> to prevent interference with the automatic action of the device. In another form, the auxiliary planes are divided into parts 1, 2, Fig. 9, which are hinged to the main supporting-aeroplane X on longitudinal and transverse axes, respectively. The planes are interconnected and operate as described above. According to the Provisional Specification, No. 23,347, the balancing device consists only of the two side planes, the tailplane and the connexions thereto being omitted. These planes serve as the main supporting-surfaces, and are flexible at the tips,