When the aircraft is stationary for more than how many minutes must all landing and taxi lights be switched off?

The correct response indicates that all landing and taxi lights must be switched off after the aircraft has been stationary for more than 10 minutes. This practice is essential for managing the aircraft's electrical load and preventing overheating of the lights, which can lead to premature failure. Additionally, turning off the lights when the aircraft is not in motion helps conserve power, contributing to overall energy efficiency during ground operations.

Understanding this limitation is crucial for flight crews, as it emphasizes the importance of proper aircraft management while on the ground, particularly in regard to ensuring the longevity of the aircraft's lighting systems and maintaining efficient power usage. The other durations mentioned in the choices do not align with the operational guidelines established for the aircraft's systems and maintenance procedures.