Description

A precision approach is an instrument approach and landing using precision lateral and vertical guidance with minima as determined by the category of operation.[1] In contrast, a non-precision standard instrument approach procedure only provides horizontal guidance.

Note. Lateral and vertical guidance refers to the guidance provided either by:

a) a ground-based navigation aid; or

b) computer generated navigation data displayed to the pilot of an aircraft.

c) a controller interpreting the display on a radar screen (Precision Approach Radar (PAR)).

The controller uses the PAR display to guide the pilot or flight crew through the final stages of landing, providing horizontal and vertical guidance. In real time, ATC directs the pilot/flight crew to change heading or adjust the descent rate to keep the aircraft on a path that allows it to touch down at the correct spot on the runway.