14 CFR 91.17 — Alcohol or Drugs
8-hour bottle-to-throttle rule, 0.04% BAC limit, and prohibition on flying under the influence of any drug that affects safety.
Regulation Text
No person may act or attempt to act as a crewmember of a civil aircraft: within 8 hours after the consumption of any alcoholic beverage; while under the influence of alcohol; while using any drug that affects the person's faculties in any way contrary to safety; while having an alcohol concentration of 0.04 or greater in a blood or breath specimen.
Note: This is an excerpt. Refer to the full regulation in eCFR for the complete text.
Plain-English Explanation
The famous 8 hours bottle to throttle rule: no alcohol within 8 hours of flying. But that is the minimum — you also cannot fly with a BAC of 0.04% or higher, or while impaired by any drug (including over-the-counter medications). Many pilots use the personal rule of 12-24 hours from bottle to throttle for extra safety margin. Violation of this regulation can result in certificate revocation and criminal charges.
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Related Regulations
14 CFR 91.3 — Responsibility and Authority of the Pilot in Command
The PIC is directly responsible for and is the final authority as to the operation of the aircraft. In an emergency, the PIC may deviate from any rule to the extent required.
§91.1314 CFR 91.13 — Careless or Reckless Operation
Prohibits operating an aircraft in a careless or reckless manner so as to endanger the life or property of another.
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