When can an aircraft without an electrical or anticollision light system be operated?

An aircraft without an electrical or anticollision light system can only be operated after sunset to sunrise if it is permitted to do so under specific conditions. This timeframe indicates that during nighttime operations, additional safety measures must typically be in place to ensure visibility and collision avoidance. Most regulations dictate that an aircraft should have functioning anticollision lights to be operated at night; thus, if such systems are lacking, the operation is typically restricted to very limited conditions.

Under this option, the correct answer acknowledges that operating without these systems during night hours is generally heavily regulated due to the heightened risk of accidents in lower visibility conditions. By stating 'after sunset to sunrise,' it captures the entire timeframe of potential darkness, highlighting the importance of visibility for operational safety during night flights.

Other options do not accurately reflect regulations regarding aircraft operation without essential lighting systems. For example, operating after dark or one hour after sunset would imply activities during the night without the necessary light systems, increasing safety risks. Operating anytime during the day would suggest it is acceptable regardless of lighting system presence, which contradicts the established safety guidelines regarding aircraft operations.