FAR 91.169 — IFR Alternate Requirements
FAR 91.169 explains what IFR flight plans must include, the 1-2-3 alternate rule, and alternate airport weather minima. Study guide for pilot students.
In Plain English
FAR 91.169 lists what you must include when filing an IFR flight plan and when you need to file an alternate airport.
Every IFR flight plan must contain the same information required by §91.153(a), plus an alternate airport — unless you qualify for the 1-2-3 rule exemption.
The 1-2-3 Rule (no alternate required) — all must be true:
- The destination has a published Part 97 (or special) instrument approach, and
- From 1 hour before to 1 hour after ETA, forecast ceiling is at least 2,000 feet above airport elevation, and
- Forecast visibility is at least 3 statute miles.
Standard alternate airport weather minima (forecast at ETA at the alternate):
- Precision approach: 600-foot ceiling, 2 SM visibility
- Non-precision approach: 800-foot ceiling, 2 SM visibility
- No approach available: must allow descent from the MEA, approach, and landing under basic VFR
For RNAV approaches with alternate minima, the rule also allows ceiling 200 ft above approach minimum and visibility 1 SM (never less than the approach minimum).
Finally, after activating an IFR flight plan, you must notify ATC or FSS when you cancel or complete the flight — this matters because IFR flight plans don't auto-close, and search and rescue could be launched if you forget.
Regulation Text
14 CFR § 91.169§ 91.169 IFR flight plan: Information required.
(a)Unless otherwise authorized by ATC, each person filing an IFR flight plan must include in it the following information:
(1) Information required under § 91.153 (a) of this part;
(2) Except as provided in paragraph (b) of this section, an alternate airport.
(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 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)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.
(c)Unless otherwise authorized by the Administrator, no person may include an alternate airport in an IFR flight plan unless appropriate weather reports or weather forecasts, or a combination of them, indicate that, at the estimated time of arrival at the alternate airport, the ceiling and visibility at that airport will be at or above the following weather minima:
(1) If an instrument approach procedure has been published in part 97 of this chapter, or a special instrument approach procedure has been issued by the Administrator to the operator, for that airport, the following minima:
(i)The alternate airport minima specified in that procedure, or if none are specified the following standard approach minima:
(A)Ceiling 600 feet and visibility 2 statute miles.
(B)Ceiling 800 feet and visibility 2 statute miles.
(ii)Ceiling 200 feet above the minimum for the approach to be flown, and visibility at least 1 statute mile but never less than the minimum visibility for the approach to be flown, and
(2) If no instrument approach procedure has been published in part 97 of this chapter and no special instrument approach procedure has been issued by the Administrator to the operator, for the alternate airport, the ceiling and visibility minima are those allowing descent from the MEA, approach, and landing under basic VFR.
(d)When a flight plan has been activated, the pilot in command, upon canceling or completing the flight under the flight plan, shall notify an FAA Flight Service Station or ATC facility.
[Docket 18334, 54 FR 34294, Aug. 18, 1989, as amended by Amdt. 91-259, 65 FR 3546, Jan. 21, 2000]
Oral Exam Questions a DPE Might Ask
Q1When are you required to file an alternate airport on an IFR flight plan?
Per FAR 91.169, an alternate is required unless the destination has a published instrument approach AND from 1 hour before to 1 hour after ETA the forecast ceiling is at least 2,000 feet and visibility at least 3 statute miles (the 1-2-3 rule).
Q2What are the standard alternate airport weather minima for filing purposes?
FAR 91.169(c) specifies that, at the ETA at the alternate, the forecast must show 600-1-2 (ceiling 600 ft, 2 SM vis) for a precision approach or 800-2 for a non-precision approach, unless the approach chart specifies different alternate minima.
Q3What if your planned alternate has no published instrument approach?
Under FAR 91.169(c)(2), if no instrument approach is available at the alternate, the forecast ceiling and visibility must allow descent from the MEA, approach, and landing under basic VFR.
Studying for a checkride?
Related Sections in Part 91