When TDZ RVR is 600+500, what lighting is required?

• A. HIRL and CL Lights
• B. RCLM only
• C. HIRL only
• D. No lights

Answer: (A)

When landing in low visibility, lighting on the runway is tied to the reported RVR values. A touchdown zone RVR of 600 feet with a midpoint RVR of 500 feet puts you in a low-visibility situation that requires enhanced runway lighting to safely guide the airplane to touchdown. High-Intensity Runway Lights along the runway edges illuminate the runway boundaries clearly, helping you see where the runway ends. Runway Centerline Lights run along the centerline to provide a continuous visual path down the runway, which is crucial when cues from outside the cockpit are limited.

So the combination of lights needed is high-intensity runway lights and centerline lights to ensure both edge definition and centerline guidance are available. Relying on centerline lights alone wouldn’t illuminate the edges, and having no lights at all would be unsafe. While having only the edge lights or only the centerline lights might seem helpful, the scenario specifies a need for both to meet the required visibility and guidance levels.