University of Virginia Library

Pressey Automatic Control.

Another ingenious system of automatic control has been perfected by Dr. J. B. Pressey, of Newport News, Va. The aeroplane is equipped with a manually operated, vertical rudder, (3), at the stern, and a horizontal, manually operated, front control, (4), in front. At the ends of the main plane, and about midway between the upper and lower sections thereof, there are supplemental planes, (5).

In connection with these supplemental planes (5), there is employed a gravity influenced weight, the aviator in his seat, for holding them in a horizontal, or substantially horizontal, position when the main plane is traveling on an even keel; and for causing them to tip when the main plane dips laterally, to port or starboard, the planes (5) having a lifting effect upon the depressed end of the main plane, and a depressing effect upon the lifted end of the main plane, so as to correct such lateral dip of the main plane, and restore it to an even keel. To the forward, upper edge of planes (5) connection is made by means of rod (13) to one arm of a bellcrank lever, (14) the latter being pivotally mounted upon a fore and aft pin (15), supported from the main plane; and the other arms of the port and starboard bellcrank levers (16), are connected by rod (17), which has an eye (18), for receiving the segmental rod (19), secured to and projecting from cross bar on seat supporting yoke (7). When, therefore, the main plane tips downwardly on the starboard side, the rod (17) will be moved bodily to starboard, and the starboard balancing plane (5) will be inclined so as to raise its forward edge and depress its rear edge, while, at the same time, the port balancing plane (5), will be inclined so as to depress its forward edge, and raise its rear edge, thereby causing the starboard balancing plane to exert a lifting effect, and the port balancing plane to exert a depressing effect upon the main plane, with the result of restoring the main plane to an even keel, at which time the balancing planes (5), will have resumed their normal, horizontal position.

When the main plane dips downwardly on the port side, a reverse action takes place, with the like result of restoring the main plane to an even keel. In order to correct forward and aft dip of the main plane, fore and aft balancing planes (20) and (23) are provided. These planes are carried by transverse rock shafts, which may be pivotally mounted in any suitable way, upon structures carried by main plane. In the present instance, the forward balancing plane is pivotally mounted in extensions (21) of the frame (22) which carries the forward, manually operated, horizontal ascending and descending plane

It is absolutely necessary, in making a turn with an aeroplane, if that turn is to be made in safety, that the main plane shall be inclined, or "banked," to a degree proportional to the radius of the curve and to the speed of the aeroplane. Each different curve, at the same speed, demands a different inclination, as is also demanded by each variation in speed in rounding like curves. This invention gives the desired result with absolute certainty.