REGULATION — LEGALLY BINDING

§ 91.167 Fuel requirements for flight in IFR conditions

14 CFR Part 91 — Subpart B—Flight Rules

Official text — 14 CFR § 91.167

REGULATION — LEGALLY BINDING

(a) No person may operate a civil aircraft in IFR conditions unless it carries enough fuel (considering weather reports and forecasts and weather conditions) to—

(1) Complete the flight to the first airport of intended landing;

(2) Except as provided in paragraph (b) of this section, fly from that airport to the alternate airport; and

(3) Fly after that for 45 minutes at normal cruising speed or, for helicopters, fly after that for 30 minutes at normal cruising speed.

(b) Paragraph (a)(2) of this section does not apply if:

(1) Part 97 of this chapter prescribes a standard instrument approach procedure to, or a special instrument approach procedure has been issued by the Administrator to the operator for, the first airport of intended landing; and

(2) Appropriate weather reports or weather forecasts, or a combination of them, indicate the following:

(i) For aircraft other than helicopters. For at least 1 hour before and for 1 hour after the estimated time of arrival, the ceiling will be at least 2,000 feet above the airport elevation and the visibility will be at least 3 statute miles.

(ii) For helicopters. At the estimated time of arrival and for 1 hour after the estimated time of arrival, the ceiling will be at least 1,000 feet above the airport elevation, or at least 400 feet above the lowest applicable approach minima, whichever is higher, and the visibility will be at least 2 statute miles.

Reproduced from the eCFR. Text as amended through 2026-07-31. Verify against the official source before relying on it operationally.

SkeyeMentor explanation

Educational — not an FAA source

In plain English

IFR fuel requirements: enough fuel to fly to the destination, then to the alternate when an alternate is required, and then for a specified additional period at normal cruising speed.

Why it matters

IFR fuel planning is tied directly to whether an alternate is required under 91.169.

Quick example

Determine the fuel required for an IFR flight where an alternate is required.

Written and reviewed by the SkeyeMentor editorial team. This explanation is a study aid, not legal advice, and it is not part of the official text above. Verify current requirements through the official source before relying on them operationally.

Is this a regulation?

Yes — this is regulatory text and is legally binding.

Text published in the Code of Federal Regulations. Regulations are legally binding on pilots and operators.

Yes — this is the text of a Federal Aviation Regulation. It is legally binding. The explanation below it is SkeyeMentor educational content, not part of the regulation.

SkeyeMentor FAA Library is an educational reference and study aid. Regulatory and FAA materials can change. SkeyeMentor provides links and contextual explanations to help pilots study, but users should verify current requirements through official FAA, eCFR and other applicable government sources before relying on them operationally. SkeyeMentor explanations are educational and are not legal advice.