For domestic US commercial aircraft, when they pull into the gate and immediately close the engines, why doesn't aircraft power fail? Ground power can't be connected yet, so it must be the APU. If that's true, then when are APUs typically started after landing? If you have both engines and the APU up, are all the bleed valves then opened?Boyd BarkerSenior Command CaptainKBOS Hub ManagerWestWind Airlineshttp://home.houston.rr.com/checklist/DFexperience.jpghttp://home.houston.rr.com/checklist/checklist.htmlMy DF737 Around the World Adventure: http://home.houston.rr.com/checklist/aroundtheworld.html

Hmm.. good question, I belive that the APU is started once you clear the active RWY and are starting to taxi to your gate."... AND I'M PROUD TO BE AN AMERICAN!"[b/]

Thanks. Anyone else?Boyd BarkerSenior Command CaptainKBOS Hub ManagerWestWind Airlineshttp://home.houston.rr.com/checklist/DFexperience.jpghttp://home.houston.rr.com/checklist/checklist.htmlMy DF737 Around the World Adventure: http://home.houston.rr.com/checklist/aroundtheworld.html

yes,that's correct,after landing they will start the APU,thus as they shutr down the engines at the gate,the APU provides eletrical power and bleed air,which is normally done by the engines if running

Hi Boyd,It depends on a number of things.1. Whether the gate has AC (three phase) external power available.2. If the airline allows single engine taxi to the gate for fuel savings.3. If the outside air temperature is moderate so that the cabin (and crew)will stay comfortable.4. And of course whether the APU is operable.Usually if the APU is not required for heating or cooling and external power is available, at least one engine will be kept runing until external is plugged in.If the APU is needed it will be started while taxiing to the gate.Hope that helps,Ed Weber Retired NWA pilot