Reporting potentially hazardous meteorological conditions and irregularities of ground facilities or navigation aids

When you encounter dangerous weather conditions or discover that a ground facility or navigation aid isn't working properly during flight, you must report it to an appropriate ground radio station as soon as practical—but only if you believe other pilots need to know about it for safety reasons.

This regulation ensures that hazardous conditions get communicated through the system so other flights can be warned or rerouted. Examples include unexpected severe turbulence, icing conditions, wind shear, a malfunctioning VOR, or misleading instrument approach lighting.

The key judgment call is yours: report when you consider the information "essential to the safety of other flights." You're not required to report every minor bump or small discrepancy, but significant hazards should be communicated. "As soon as practicable" means when workload permits—aviate and navigate first, then communicate when it's safe to do so. This applies specifically to Part 135 operations (commuter and on-demand carriers).

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*