Regulation Text
(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.
Research Notes
Section 91.187 — Operation under IFR in controlled airspace: Malfunction reports — requires the pilot to report any equipment malfunction that affects the aircraft's capability to operate under IFR.
What must be reported (paragraph a): The pilot must report to ATC any loss of:
- (1) VOR, TACAN, ADF, low frequency navigation receiver capability
- (2) Complete or partial loss of ILS receiver capability
- (3) Impairment of air/ground communications capability
- (1) Aircraft identification
- (2) Equipment affected
- (3) Degree to which the equipment is impaired
- (4) Nature and extent of assistance the pilot desires from ATC
Why this matters operationally: ATC routes IFR traffic based on what equipment the aircraft can use. If a VOR fails en route, ATC needs to know so they can vector the aircraft using radar or assign a different route. Without the report, the pilot might receive a clearance the aircraft can't fly.
The minimum equipment for departure: If equipment is inoperative at the gate, the pilot must determine whether the flight can proceed IFR — either with an approved MEL, or per § 91.213(d) for non-MEL aircraft, or by declining the flight. § 91.187 covers IN-FLIGHT failures.
GPS RAIM and WAAS reports: Modern IFR uses GPS. The pilot should report GPS RAIM warnings, WAAS reception loss, or significant GPS accuracy degradation under § 91.187's catch-all 'impairment' wording.
Reference: AIM 5-3; FAA-H-8083-16 Chapter 8.
Amendment History
Amendment History Coming Soon
Every time this regulation changes, we'll record it here — the date, what was amended, and a plain-English summary of what shifted.