PAPI Light

A Precision Approach Path Indicator (PAPI) is a visual aid that provides guidance to aircraft during the approach phase of a landing. It consists of a row of lights located beside the runway, typically in two or four light units. These lights project a visual signal to the pilot, indicating whether the aircraft is above, below, or on the correct glide path for a safe landing.

The PAPI light uses a combination of red and white lights to convey this information. When an aircraft is below the glide path, more white lights are visible; when above the glide path, more red lights are visible. If the aircraft is on the correct glide path, an equal number of red and white lights are seen. This clear visual indication helps pilots make real-time adjustments to their approach angle, ensuring a safe and precise landing.

PAPI systems are widely used at airports around the world to assist pilots in conducting accurate and consistent landings, especially during low-visibility conditions. Their intuitive design and effectiveness in guiding aircraft to a safe touchdown point make them an essential component of modern aviation infrastructure.