Definition
A fault in an electrical, electronic, or mechanical system that appears and disappears unpredictably rather than remaining present continuously. The system functions normally most of the time, but fails briefly under certain conditions — often related to vibration, temperature, moisture, or movement of a connector or wire — then resumes normal operation before the fault can be located or measured.
Plain English
A problem that comes and goes. The equipment works fine, then fails for a moment, then works fine again, which makes the fault hard to find because it usually isn't happening when you go looking for it.
Context Anchor
Seen in aircraft maintenance write-ups, troubleshooting, electrical system checks, and pilot reports of problems that come and go.
Derivation
From Latin intermittere, meaning 'to leave off' or 'to pause between.' The word describes something that stops and starts rather than running continuously — exactly the behavior of this kind of fault.
Why Pilots Care
An intermittent fault can cause sudden loss of instruments or systems during flight, making diagnosis difficult and increasing risk if left unresolved.
Intuition Check
Do not assume an intermittent fault is fixed just because it is not happening right now. Intermittent means the problem may disappear temporarily and return later.
Example Sentence 1
The pilot wrote up an intermittent fault in the number two communication radio, noting that it cut out only during steep turns.
Example Sentence 2
During the flight the pilot noticed an intermittent fault in the GPS that cleared after the aircraft leveled off.