PAPI and APAPI systems provide pilots with a safe and accurate glide slope on final approach to the runway. The precision approach path indicator (PAPI) uses a row of light housing assemblies (LHAs) placed perpendicular to the runway approach path. Pilots can easily determine if their approach is too high, too low, or correctly on slope through combinations of red and white lights. The Carmanah PAPI/APAPI is available in three basic models with multiple configuration options to exceed ICAO, FAA, and STANAG requirements.