REGULATION — OFFICIAL DEFINITION

Flight level

14 CFR § 1.1 — Definitions

Official definition — 14 CFR Part 1

REGULATION — OFFICIAL DEFINITION

Flight level means a level of constant atmospheric pressure related to a reference datum of 29.92 inches of mercury. Each is stated in three digits that represent hundreds of feet. For example, flight level 250 represents a barometric altimeter indication of 25,000 feet; flight level 255, an indication of 25,500 feet.

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.