When setting up marking lights for additional aircraft that have to land after the first, what is the spacing between the lights and the TDP?

• A. 10 meters apart for cargo; 5 meters for noncargo; TDP left of both lights
• B. 15 meters apart for all aircraft
• C. 10 meters apart for cargo; 5 meters for noncargo; TDP left of both lights
• D. 20 meters apart for all aircraft

Answer: (C)

The main idea is to position the lighting so follow-on aircraft have a clear, unambiguous landing path when another plane is landing after the first. For cargo aircraft, space the lights 10 meters apart; for noncargo aircraft, space them 5 meters apart. The touchdown point (TDP) is placed to the left of both lights, creating a consistent reference line that the pilot can follow as they align with the LZ. This arrangement helps maintain proper lateral positioning and ensures the TDP remains visible and distinct from the lighting pattern, reducing confusion in the approach sequence. The differing spacings reflect the need to keep the light signal legible for different aircraft types with varying sizes and approach characteristics.