SYSTEM DESCRIPTION

The PAPI is a visual guidance landing system that is installed alongside an airport runway or at a heliport to provide pilots of landing aircraft with accurate approach path information. The system consists of four Lamp Housing Assemblies (LHA), a Power and Control Assembly (PCA), an Aiming Instrument Set, and the Remote Monitoring System (RMS) Assembly. The four Lamp Housing Assemblies provide the incoming aircraft pilot with a light pattern to indicate the proper aircraft glide path. If the aircraft is more than 0.5 degrees above the proper glide path, the pilot sees four white lights. Between 0.17 degrees and 0.5 degrees above the glide path, the rightmost light is red while the others are white. When the pilot has the aircraft on the correct flight path, the two right lights are red and the two left lights are white. Three lights appear red while the remaining one appears white if the aircraft is between 0.17 and 0.5 degrees below the glide path. All four appear red if the aircraft is more than 0.5 degrees below the glide path.

The on-off condition of the PAPI is controlled remotely. The PAPI lamps operate at two intensity levels, low for night operation and high for day operation. These intensity levels are controlled by ambient lighting conditions. PAPI parameters and status can be monitored remotely with the Remote Monitoring Subsystem.