Definition
A category of instrument approach that provides lateral (course) guidance to the runway or landing area but does not provide vertical (glidepath) guidance certified to precision standards. The pilot descends in steps to a Minimum Descent Altitude (MDA) and must visually acquire the runway environment before continuing below that altitude.
Plain English
An instrument approach that tells you how to line up with the runway but doesn't give you a guided path down. You step down to a fixed minimum altitude and then look outside for the runway before going lower.
Context Anchor
Seen on instrument approach charts and in discussions of IFR approaches to airports and heliports.
Derivation
‘Precision’ comes from Latin praecisio, meaning ‘a cutting off’ or ‘exactness.’ A precision approach gives an exact vertical path; a non-precision approach lacks that exact vertical guidance.
Why Pilots Care
Non-precision approaches usually require higher minimum altitudes and more visual references before landing, increasing workload and weather limits.
Intuition Check
Do not read non-precision as “not accurate.” Here it means “no approved vertical glidepath is provided,” so the pilot must manage the descent by the published altitude restrictions.
Example Sentence 1
Because the heliport only had a non-precision approach, the crew planned to level off at the MDA and look for the landing area.
Example Sentence 2
Because the heliport had no ILS, the crew planned a non-precision procedure with a higher minimum descent altitude.