In addition to the above, the APU may be off in line with company standard operating procedures:
Pull onto stand, shut down right engine and keep left engine running until ground power connected.
This saves one APU start cycle, supposedly making it need less engineering work, and supposedly resulting in reduced fuel consumption.
Notice that I am not entirely convinced that this is clever or effective.
Last edited by Deaf Tortoise; 21st June 2008 at 07:59.