Experience in instrument installation and maintenance is gained by students at the American School of Aircraft Instruments, Glendale, Calif., with a small monoplane that does everything but take off. With power supplied -by, an electric motor, the plane can be made to roll, pitch and yaw while the instruments respond to the movements exactly as they would under actual flight. The plane also serves as a testing device for the automatic pilot. Instruments in the machine are operated through vacuum and hydraulic systems.