Definition
Instrument approach procedures that provide the pilot with both lateral guidance (alignment with the runway centerline) and vertical guidance (a defined glidepath to the runway), allowing descent to lower minimums than non-precision approaches. Examples include the Instrument Landing System (ILS), Precision Approach Radar (PAR), and GBAS Landing System (GLS).
Plain English
An instrument approach that tells the pilot both where to go side-to-side and how steeply to descend, all the way down to the runway. Because both kinds of guidance are present and accurate, the pilot can legally fly closer to the ground in poor visibility before needing to see the runway.
Context Anchor
Seen in instrument flying, weather planning, and approach procedure discussions, especially when ceiling or visibility is low.
Derivation
"Precision" comes from the Latin praecisio, meaning "a cutting off" or "exactness." Here it signals that the approach gives an exact, measured descent path -- not just a heading and a minimum altitude. The vertical guidance is what makes it "precise."
Why Pilots Care
They allow lower landing minimums, increasing the chance of completing a flight safely in marginal weather.
Intuition Check
Precision does not just mean “careful” here. In this term, it means the procedure gives both runway alignment guidance and descent-path guidance.
Example Sentence 1
With the ceiling reported at 300 feet, the crew briefed the ILS as a precision approach to Runway 27.
Example Sentence 2
Weather conditions forced the crew to request a precision approach instead of a visual one.