Plain English Meaning

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.

Full 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.

Context Anchor

Seen in the IMSAFE checklist before flight, where checks whether alcohol use or aftereffects could affect fitness to fly.