What must be displayed by an aircraft left on an active maneuvering area at night?

Operating wingtip and tail lights must be displayed by an aircraft left on an active maneuvering area at night to ensure visibility and safety. These lights are critical for alerting other aircraft and ground personnel to the presence of the stationary aircraft, reducing the risk of collisions and facilitating safe operations in low visibility conditions. Wingtip lights typically emit different colors—green on the right wing and red on the left—helping to indicate the orientation of the aircraft. The tail light is often white and further enhances visibility from behind.

Other options may seem beneficial but do not conform to the specific requirements for nighttime visibility on an active maneuvering area. Markers or flags, while useful in certain contexts, do not provide the necessary illumination to alert others in the critical conditions of nighttime operations. Therefore, ensuring that the operating wingtip and tail lights are activated is a standard safety measure for aircraft left on active areas after dark.