Abstract: A direct current (DC) powered gyroscope (41) utilizes an alternating current (AC) subsystem in which electrolytic switches (49, 50) control torquer motors (45, 46). The alternating current is obtained from commutation circuitry (21-23) in the gyroscope spin motor, so that the spin motor performs an inverter function. Advantages include reduced costs and the ability to operate the gyroscope (41) without an AC power supply.

Abstract: An erection system (22) which is responsive to the flow of air for erecting a gyroscope (1) is diclosed. The erection system includes a plurality of channels (26,28,30,32) having balls (42) disposed therein. The balls (42) are responsive to the gyroscope (1) being tilted from an erect attitude by a first relatively small predetermined angle (0.5.degree.) for rolling in the channels (20,28,30,32) to create an unbalanced flow of air through the erection system (22), which provides a force to erect the gyro (1), and are responsive to the gyroscope (1) being tilted by a second relatively large predetermined angle (10.degree.) for rolling in the channels (26,28,30,32) to negate the unbalanced air flow which disables the erection system (22).