What is the role of the controller regarding the drain masts heating?

The controller's role regarding the drain masts heating is to apply 115V AC power for heating. This function is vital for preventing the freezing of water collected in the drain masts, especially in colder weather conditions. The electric heating elements need a reliable power source to operate effectively, ensuring that the drains remain unobstructed by ice, which could lead to other operational issues.

While regulating fan speed, controlling coolant flow, and monitoring fuel levels are important systems in the aircraft, they are not directly related to the specific function of heating the drain masts. The primary focus of the controller in this context is to ensure that adequate heat is applied to prevent any adverse effects caused by cold temperatures.