Definition
A standard instrument approach procedure that provides lateral guidance (course alignment to the runway) but does not provide vertical guidance meeting precision-approach standards. The pilot uses published step-down altitudes to descend toward a Minimum Descent Altitude (MDA), at which the runway environment must be in sight to continue.
Plain English
An instrument approach that tells you which direction to fly to line up with the runway, but does not give you a continuous glide path down to it. You manage the descent yourself using altitudes printed on the chart.
Context Anchor
Seen in instrument approach briefings, approach charts, weather minimums, and air traffic control clearances for approaches such as localizer-only, VOR, or RNAV approaches without vertical guidance.
Derivation
Nonprecision' is used here in a technical sense: it does not mean sloppy or inaccurate. It means the approach lacks the precise vertical guidance signal (such as an ILS glideslope) that defines a precision approach.
Why Pilots Care
Sets the minimum descent altitude and visibility requirements that determine whether a landing is legal and safe in marginal weather.
Intuition Check
Do not read “nonprecision” as “careless” or “less accurate flying.” It means the approach lacks approved electronic vertical guidance; the pilot must still fly it precisely.
Example Sentence 1
With the ILS out of service, the crew briefed the VOR approach as a nonprecision approach to Runway 27.
Example Sentence 2
Because the airport only had a nonprecision approach available, the crew planned for higher minimums and a possible missed approach.