Definition
In the aeromedical context of the IMSAFE self-assessment checklist, alcohol refers to the consumption of any beverage or substance containing ethanol, which impairs judgment, reaction time, coordination, and the ability to process information at altitude. Federal Aviation Regulations prohibit acting as a crewmember within 8 hours of consuming alcohol, while under its influence, with a blood alcohol concentration of 0.04 percent or greater, or while using any drug that affects faculties contrary to safety.
Plain English
Drinking. The 'A' in IMSAFE asks whether you have had any alcohol recently, because even small amounts can affect how well you fly — and the effects last longer than most people think.
Context Anchor
Seen in the IMSAFE checklist before flight, where the pilot checks whether alcohol use or aftereffects could affect fitness to fly.
Derivation
From the Arabic 'al-kuhl,' originally referring to a fine powder used as eye makeup, later extended to any refined or distilled substance, and eventually to the specific compound (ethanol) found in beer, wine, and spirits. Knowing the word once meant 'something distilled' is a useful reminder that alcohol is a chemical agent acting on the body, not just a social drink.
Why Pilots Care
The FAA prohibits flight within 8 hours of drinking or with a blood alcohol concentration of 0.04 percent or higher because alcohol directly degrades the skills needed for safe flight.
Grounding Statement
If alcohol or its aftereffects could change how you think, see, react, or decide, it matters before flight.
Intuition Check
Alcohol does not only matter when a pilot feels drunk. It also matters after drinking, during a hangover, or whenever judgment and reaction time may still be reduced.
Example Sentence 1
Running through IMSAFE before the flight, she paused on Alcohol and decided that although she was past the 8-hour limit, the late dinner with wine meant she should delay the trip until afternoon.
Example Sentence 2
During the preflight briefing the instructor reminded the student that any alcohol in the previous twenty-four hours would disqualify them from the lesson.