Nimrod
Indeed it was the Airstart valve that was stuck open. The in flight drill at the time was to remove the bulb from the warning light as, obviously, the warning must be spurious in flight!
Result, the starter spins up to about 13,000 RPM and disintegrates putting metal into the tanks - FIRE!
Apparently, the guys could see the wing glowing and then they could see right through it - but I don't know if that's myth or not.
One of the Crew seats detached from the rail and ended up in a hole in the floor - safe aircraft we fly!!
Vage!