What Are PAPI Lights – Infographic
What are PAPI Lights?
PAPI (precision approach path indicator) lights are a set of lights positioned beside the runway which provide pilots with a visual indicator of their aircraft’s position relative to the correct glidepath for the runway. The lights are are colour-coded and are typically placed approximately 300 metres from the landing threshold of the runway on the left-hand side.
Initially devised in 1974 by Tony Smith and David Johnson, PAPI lights took a further two years of development to be fully viable but are now used across airfield around the world to help pilots land safely
Traditionally, PAPI lights are a series of four red and white lights which transition in colour depending on the pilot’s angle – more red lights indicate the pilot is too low, while more white lights indicate the pilot is too high. Two of each shows the pilot is on the correct path for landing. There is also a two light version. The below infographic provides and easy-to-understand overview of the different types of PAPI lights alongside information on how PAPI lights work. Feel free to use the embed code below to share it on your website.