What you see above is an APU from a VC10, the Rolls Royce Artouste. The originals were made by Turbomeca, however this variant was made under licence by RR.
Fortunately this was a complete unit including the starter so it did not take long to get it running. I had to re-wire the various actuators and sensors to a more readily available connector and knock up a control box.
We decided to add a big alternator to it and use it to power some light bulbs…probably not the most efficient generator in the world.