What is one of the conditions for towing an aircraft at night on an active movement area?

One of the critical conditions for towing an aircraft at night on an active movement area is that the aircraft must display operating wingtip and tail lights. This requirement ensures that the aircraft is visible to other pilots and ground personnel, which is essential for maintaining safety in a low-light environment. The illumination provided by these lights helps to prevent collisions and allows for better situational awareness for everyone operating in the movement area.

While being illuminated by a spotlight enhances visibility further, it is the mandatory functioning of the wingtip and tail lights that directly complies with aviation regulations regarding night operations. Additionally, having authorized towing vehicles and clarity around obstructions is vital, but they are secondary to the immediate necessity of ensuring visibility through the aircraft's lighting.