Definition
Rocky Mountain Metropolitan Airport (ICAO: KBJC, FAA: BJC) is a public-use, non-towered-to-towered general aviation airport located in Broomfield, Colorado, at a field elevation of approximately 5,673 feet MSL. It sits just east of the Rocky Mountain foothills and serves the Denver metropolitan area as a reliever airport for Denver International. Its high elevation and proximity to mountainous terrain make it a frequently cited example in training materials for density altitude effects and terrain-influenced wind and performance considerations.
Plain English
A busy general aviation airport near Denver, sitting more than a mile above sea level and right next to the Rocky Mountains. Because it is so high and so close to the mountains, airplanes do not perform as well there as they would at a lower airport, and the wind can behave in tricky ways.
Context Anchor
You may see KBJC on charts, in flight planning tools, in weather reports, or in FAA training examples that refer to a specific airport.
Derivation
The 'K' prefix marks it as a contiguous-United-States ICAO identifier, and 'BJC' is the original three-letter FAA identifier (historically tied to the airport's earlier name, Jefferson County Airport — 'BJC' from 'Broomfield/Jefferson County'). Knowing the K-prefix convention helps pilots recognize any four-letter identifier starting with K as a U.S. airport.
Why Pilots Care
Pilots must use the correct airport identifier when filing flight plans, reviewing charts, requesting clearances, and communicating with air traffic control to ensure they reach the intended destination.
Intuition Check
Do not read KBJC as a word or as the airport’s name. It is an airport identifier: a short code that points to one specific airport.
Example Sentence 1
On a hot summer afternoon at KBJC, the density altitude was over 9,000 feet, so the pilot recalculated takeoff distance and climb performance before departing.
Example Sentence 2
Approach control cleared the aircraft for the visual approach to runway 29L at KBJC.