7.2 Precision Approach Indicators (PAPI)

7.2.1 PAPIs are lights that are displayed to the left of the landing threshold. They give pilots the ability to accurately judge their descent path down to the runway.

7.2.2 To maintain the correct glide path, the pilot must keep 2 red and 2 white lights showing. The lights usually keep the pilot on a 3° slope down to the runway.

7.2.3 Once the correct glide path is shown, the correct rate of descent must be maintained down to the runway. This is done by multiplying your ground speed on finals by 5 (or by adding a zero onto your speed,
then dividing by 2).

7.2.4 PAPIs are only found at larger airfields. You won’t find this installation at every airport, it is not a requirement.