Specifically, the Federal Aviation Administration rulebook states that a pilot may not use alcohol within 8 hours of a flight and cannot have a blood alcohol content above 0.04%.

The standard FAA rule for pilots is known as "Bottle to Throttle," which mandates that a pilot must not consume any alcohol within 8 hours of flying. Additionally, a pilot cannot have a Blood Alcohol Concentration (BAC) of 0.04% or higher. A supportive peer "professional standard" update: while 8 hours is the legal minimum, many major airlines in 2026 enforce a much stricter 12-to-24-hour rule to ensure total sobriety and the absence of hangovers, which can impair judgment even if BAC is zero. Furthermore, pilots are prohibited from flying if they are "under the influence" of alcohol in any capacity, even if they meet the time and BAC requirements. In 2026, pre-flight "breathalyzer" checks have become more common for commercial crews. The logic is simple: altitude magnifies the effects of alcohol on the brain and coordination, making even a "minor" impairment potentially catastrophic at 35,000 feet.