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REGULATION — OFFICIAL DEFINITION

Mach number

14 CFR § 1.1 — Definitions

Official definition — 14 CFR Part 1

REGULATION — OFFICIAL DEFINITION

Mach number means the ratio of true airspeed to the speed of sound.

Reproduced verbatim from the eCFR. Regulatory definitions control how the term is used throughout 14 CFR.

Is this a regulation?

Yes — this is regulatory text and is legally binding.

Definition published in 14 CFR Part 1. Regulatory definitions are legally binding wherever the defined term is used in 14 CFR.

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.