Originally Posted by
MATMAX
not available or unserviceable ?
heard about ASU ? Air Start Unit ...
of course i do know what an air starter is good for. but what do you do when there is none and you don't have a working APU aboard? you have to keep 1 engine running, thats why this procedure exists in the manuals. but yes: off topic, just wanted to point out you can have various things going on during refuelling. not everything has to be shut down.