What does a green light indicate in a Tricolor VASI system?

In a Tricolor Visual Approach Slope Indicator (VASI) system, a green light indicates that the aircraft is on the glideslope. The system is designed to provide visual guidance to pilots during the approach phase of landing. The different colors represent various altitude status relative to the ideal glideslope path.

When the green light is displayed, it signifies that the aircraft is at the correct altitude to intercept and maintain the desired approach slope, allowing for a safe and optimal landing trajectory. Understanding this signal is crucial for pilots, as it ensures they are properly positioned on approach to the runway. Proper interpretation of the VASI signals, including the meaning of the green light, is essential for maintaining situational awareness and achieving a successful landing.