Posted on 11 July 2011 at 08:06h

I was sitting on the airplane coming back from a workshop in Kazakhstan and got to thinking about the lights. There are a lot of lights in a plane and the must consume a fair amount of electrical energy but where is the generator? In a car the generator is connected to the drive shaft via a rubber belt but what about a jet engine? There is a drive shaft or axle in the centre of the engine but where is the generator? I didn't think it would be possible for the generator to be connected directly to the axle since it then it would be in the middle of the engine and a "fan belt" seemed out of the question since it would have pass through the flow of gas. I couldn't think of the answer so when I got home I looked it up and and found the answer that there is a bevel gear connected to the axle that turns a rod connected to a generator outside the engine, probably in that lump connecting the engine to the wing. Some planes also have a wind turbine underneath the fuselage if the jet engines fail. When standing at the airport the generators don't work and batteries are heavy so the plane has to be plugged in to the mains.