Greetings,
Bean counters
have decided that it is expensive to leave the APU runing
, so we have to shut it down as soon as no longer required.
Not so long ago we use to do PAcks on APU takeoff, even that is scrapped.
Although nowadays APU have a cool down cycle, big thermal variations in a short cycle is not metal friendly, so in order to save the cost, we might have one day to pay the price.
