Precision approach path indicator (PAPI)

Definitions

• A system of lights similar to the V ASI, but consisting of one row of lights in two- or four-light systems. A pilot on the correct glideslope will see two white lights and two red lights. See VASI.
• A system of lights similar to the VASI, but consisting of one row of lights in two- or four-light systems. A pilot on the correct glide slope will see two white lights and two red lights. See VASI.

References

• Instrument Flying Handbook, Federal Aviation Administration, 2014
• Pilot's Handbook of Aeronautical Knowledge, Federal Aviation Administration, 2023