RTILS (Runway Threshold Lighting) are described as:

RTILS (Runway Threshold Lighting) are described as:

• A. A single flashing light at midpoint of the runway.
• B. Two synchronized flashing lights, one on each side of the runway landing threshold facing the approach area.
• C. A rotating beacon near the threshold.
• D. A pair of blue edge lights along the runway.

Answer: (B)

Runway Threshold Lighting are placed at the threshold to clearly mark where the landing area begins. They consist of two synchronized flashing lights, one on each side of the runway threshold, facing the approach path. The paired, coordinated flashes create a distinctive cue that helps pilots identify the exact threshold location and align their approach, especially in low visibility or at night. This setup is different from a single light at the midpoint, a rotating beacon (which serves a broader airport signaling purpose), or blue edge lights that run along the sides to outline the runway rather than highlight the threshold itself.

Runway Threshold Lighting are placed at the threshold to clearly mark where the landing area begins. They consist of two synchronized flashing lights, one on each side of the runway threshold, facing the approach path. The paired, coordinated flashes create a distinctive cue that helps pilots identify the exact threshold location and align their approach, especially in low visibility or at night. This setup is different from a single light at the midpoint, a rotating beacon (which serves a broader airport signaling purpose), or blue edge lights that run along the sides to outline the runway rather than highlight the threshold itself.