Question by Jona: why do aircraft engines continue to spin even when they are on the ground?
Jet engine turbines spin slowly even when the a/c is at the gate. Is this just the wind blowing them or is there some reason to keep them spinning by powering them.
Answer by zhornback
The aircraft draws electrical power from the turbines’ rotation…like a wind farm generator. So if the plane is disconnected from the airport (meaning not drawing power from the airport terminal, regardless of if it is physically connected or not) and the pilots need power, at least one engine will continue to idle while the plane is on the ground, to power the plane’s systems. Not sure how many engines are needed to power the plane, but thats what they are for.
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