Definition
A published instrument approach procedure that provides lateral (side-to-side) course guidance to a runway or airport, but does not provide electronic vertical (glidepath) guidance certified to precision standards. The pilot descends in steps to published minimum altitudes until reaching the missed approach point, where the runway environment must be in sight to land. Examples include VOR, NDB, LOC (localizer-only), and many older RNAV (GPS) LNAV approaches.
Plain English
An instrument approach that tells you where to fly left and right, but not a continuous up-and-down path down to the runway. You step down to set altitudes on your own and look for the runway by a certain point. If you see it, you land. If not, you go missed.
Context Anchor
Seen in instrument flying, approach charts, and emergency planning for getting safely to an airport when outside visual references are lost.
Derivation
"Non-precision" simply means "not precision." A precision approach, by definition, includes certified electronic vertical guidance (like an ILS glideslope). Anything published as an instrument approach that lacks that certified vertical guidance falls into the non-precision category. "IAP" stands for Instrument Approach Procedure — the formal published procedure flown by reference to instruments.
Why Pilots Care
Sets the minimum descent altitude and visibility requirements that directly affect go/no-go decisions and terrain clearance in low-visibility conditions.
Intuition Check
Do not read “non-precision” as careless or inaccurate. It means the approach category does not provide approved vertical path guidance; the pilot still flies it precisely.
Example Sentence 1
The VOR approach into the field is a non-precision IAP, so we briefed the step-down altitudes and set a higher minimum descent altitude than we would on an ILS.
Example Sentence 2
During IIMC recovery the crew flew the non-precision IAP while maintaining a steady descent rate to the published minimum altitude.