1 definition by ImThePilot
PAPI - aviation term meaning Precision Approach Path Indicator. A set of four lights to the side of a runway set on the glideslope. If they are shining 4 red, you are two low. 2 red to white, you are just right. 2 white means you are too high.
We're coming down right on the PAPI.
by ImThePilot May 26, 2015