What is the minimum requirement to operate a gyroscopic instrument at the proper speed?

To operate a gyroscopic instrument effectively, it is essential to meet the minimum required vacuum and the rated Cubic Feet per Minute (CFM). Gyroscopic instruments, such as artificial horizons or gyrocompasses, rely on a stable, high-speed rotor to maintain their accuracy and performance.

The performance of these instruments is contingent upon a sufficient vacuum pressure to spin the gyroscope at the required speed. Insufficient vacuum will result in inadequate rotation speed, which directly affects the instrument's accuracy and reliability. The rated CFM specifies the flow of air required to sustain that vacuum level, ensuring the gyroscope can maintain the necessary speed for accurate readings.

By focusing on the vacuum and rated CFM as the criteria, one recognizes that both parameters are critical for proper operation, as they ensure the gyroscope achieves the optimal performance characteristics necessary for reliable flight data interpretation.