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    Type Alias AltitudeReference

    AltitudeReference: "MSL" | "AGL" | "SFC"

    The reference datum for a vertical altitude bound sourced from FAA NASR data.

    • MSL - feet above mean sea level; comparable directly to aircraft altitude
    • AGL - feet above ground level; requires terrain elevation to convert to MSL
    • SFC - surface/ground level; treated as 0 ft MSL for query purposes