What is the indication of a vacuum system failure in an aircraft?

A vacuum system failure in an aircraft typically leads to the failure of critical flight instruments that rely on the vacuum system, such as the attitude indicator and heading indicator. When the vacuum system fails, the instruments can become unreliable, leading to erratic or completely non-functional readings. This is crucial for pilots, particularly in instrument flight conditions, as they depend heavily on these instruments for safe navigation and aircraft control.

The term "stupid instrument failure" likely refers to a loss of reliable feedback from these essential instruments, highlighting the fact that they may give misleading or erratic readings that can confuse the pilot. Understanding the significance of a vacuum system failure underlines the importance of instrument system checks and maintenance to ensure the reliability of critical flight data. In such a situation where the instruments are not functioning correctly, a pilot must be prepared to transition to other forms of navigation or rely on backup systems to maintain control of the aircraft.