IFR Malfunction Reports

FAR 91.187 — IFR Malfunction Reports

FAR 91.187 requires IFR pilots in controlled airspace to report nav, approach, or comm equipment failures to ATC. Learn what to report and how.

In Plain English

FAR 91.187 sets the reporting requirements for equipment failures when you're operating IFR in controlled airspace. If something breaks that affects your ability to navigate, fly approaches, or communicate, you must tell ATC as soon as practical.

The rule applies to malfunctions of:

Navigational equipment (e.g., GPS, VOR, ILS receivers)
Approach equipment (e.g., glideslope, localizer)
Communication equipment (e.g., radios, transponder)

When you make the report, you must include:

Aircraft identification (your callsign)
The equipment affected
The degree to which your IFR capability in the ATC system is impaired
The nature and extent of assistance you want from ATC

Why it matters operationally: ATC builds your clearance and separation around the equipment you have. If your GPS dies on a GPS approach, controllers need to know immediately so they can reroute, vector, or assign a different approach. Speaking up early keeps you legal, safe, and out of an unflyable situation.

Regulation Text

14 CFR § 91.187

§ 91.187 Operation under IFR in controlled airspace: Malfunction reports. (a) The pilot in command of each aircraft operated in controlled airspace under IFR shall report as soon as practical to ATC any malfunctions of navigational, approach, or communication equipment occurring in flight. (b) In each report required by paragraph (a) of this section, the pilot in command shall include the— (1) Aircraft identification; (2) Equipment affected; (3) Degree to which the capability of the pilot to operate under IFR in the ATC system is impaired; and (4) Nature and extent of assistance desired from ATC.

Oral Exam Questions a DPE Might Ask

Q1If your DME fails while you're IFR in controlled airspace, what are you required to do?

Per FAR 91.187, I must report the malfunction to ATC as soon as practical, since DME is navigational equipment affecting my IFR capability.

Q2What specific information must you include in an IFR equipment malfunction report?

FAR 91.187(b) requires aircraft identification, the equipment affected, the degree to which my ability to operate IFR in the ATC system is impaired, and the nature and extent of assistance I need from ATC.

Q3Does FAR 91.187 apply to every flight, or only certain operations?

It applies only to aircraft operated in controlled airspace under IFR; FAR 91.187 doesn't impose this specific reporting duty on VFR flights or operations outside controlled airspace.

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Related Sections in Part 91

§ 91.1

Part 91 Applicability