Flight, June 26, 1909
THE BOKOR TRIPLANE.
IN the accompanying photograph we illustrate the triplane with which Mr. Morris Bokor is experimenting at the American Aeronautic Society's grounds at Morris Park, New York. The three main planes measure 25 ft. from tip to tip, and are 6 1/2 ft. wide, giving a lifting surface of 507 sq. ft. A further 70 sq. ft. are obtained from the horizontal rudder, the dimensions of which are 14 ft. by 2 1/2 ft., while another addition is secured by the two planes which are mounted at a sharp dihedral angle behind the two upper main planes. The machine in going order with Mr. Boker on board weighs 1,181 lbs. The middle main plane is placed 5 ft. above the lower one, while the top one is 6 ft. from the one below it.
Two 8-ft. wooden propellers, of 11 ft. pitch, are driven by chains from the 4-cylinder 4-in. motor, the gear ratio being 3 1/2 to 1. One special feature of the machine is that the aviator's seat is mounted on a pendulum, with the object of obtaining automatic stability. When the machine tips to one side or the other, the flexible rear edges of the main planes are warped by means of cables from the pendulum. Since this photograph was taken, the machine has been mounted on skids, and for starting it is mounted on a little four-wheeled truck, which is left behind when the machine rises in the air.