Definition
The use of alcohol, illegal drugs, prescription medications, or over-the-counter medications in a way that impairs judgment, coordination, or physical condition to a degree that compromises the safe operation of an aircraft or violates FAA regulations.
Plain English
Using alcohol or any drug — legal or illegal — in a way that affects how well a person can think, react, or fly safely.
Context Anchor
Seen when applying for or holding an FAA medical certificate, especially in questions about alcohol use, drug use, medications, driving history, and drug testing.
Derivation
From Latin 'sub' (under) + 'stare' (to stand), giving 'substance' meaning the underlying material of something — here, anything ingested that affects the body. 'Abuse' comes from Latin 'abusus,' meaning misuse or use away from the proper purpose. Together: using a substance in a way other than intended, to harmful effect.
Why Pilots Care
A history of substance abuse can prevent issuance or renewal of a medical certificate.
Intuition Check
Do not read substance abuse as only meaning addiction. In the FAA medical context, even an unsafe event or misuse involving alcohol, drugs, or medication can matter if it raises a safety concern.
Example Sentence 1
The applicant disclosed a past history of substance abuse, which triggered an FAA review before the medical certificate could be issued.
Example Sentence 2
The examiner reviewed the pilot's record for any signs of substance abuse before approving the certificate.