Vacuum System
What is vacuum system?
A vacuum system uses a pump (or venturi) to draw air through certain gyroscopic flight instruments—typically the attitude indicator and heading indicator—spinning their gyros so they can function. The system must operate within design suction limits; if suction is too high or low, or if instrument parts are worn or broken, the gyro indications become unreliable. Think of it as the "wind" that keeps your gyros spinning—lose suction and those instruments slowly fail.
Also known as: vacuum gyroscopic system, suction system, pneumatic instrument system
Studying for an FAA written test?
Terms like vacuum system show up on the FAA knowledge test. Study them in context with ACS-aligned practice questions, AI explanations, and the cited FAA handbook reference behind every answer — free to start.