Airport – Precision Approach Path Indicator (PAPI) v2
A precision approach path indicator (PAPI) consists of four sets of lights in a line perpendicular to the runway, usually mounted to the left side of the runway. [Wikipedia]
White (W) and red (R) lights indicate the pilot how far off the glide slope the aircraft is.
A mnemonic to remember the colors and their meaning is:
WWWW – White over White, you’re high as a kite. / you’ll fly all night
WWRR – Red over White, you’re alright.
WRRR – White over Red, unsaid / you’re under head
RRRR – Red over Red, you’re dead.
Can be found under the airport category and is freely placeable!