Single Engine Taxi
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Join Date: Apr 2008
Location: Galway, Ireland
Age: 32
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Single Engine Taxi
Last summer I flew with US Airways from Philadelphia International Airport. The aircraft was a Boeing 757. Typical of most Cactus flights, we taxied to the active with only Engine No. 2 running.
My questions are:
- What are the procedures for a single-engine taxi?
- Is the APU left on for the entire taxi?
- When is the other engine started up?
- Is there a certain duration which engines must be spooled up for before they are TOGA/FLEX-rated?
- Does keeping the second engine off really save that much fuel considering the running of the APU and the additional thrust required to move the aircraft?
Any input on any equipment from pilots or engineers would be very much appreciated. Thanks a lot guys!
Aaron, Ireland.
My questions are:
- What are the procedures for a single-engine taxi?
- Is the APU left on for the entire taxi?
- When is the other engine started up?
- Is there a certain duration which engines must be spooled up for before they are TOGA/FLEX-rated?
- Does keeping the second engine off really save that much fuel considering the running of the APU and the additional thrust required to move the aircraft?
Any input on any equipment from pilots or engineers would be very much appreciated. Thanks a lot guys!
Aaron, Ireland.
Join Date: Dec 2005
Location: Manchester
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AFAIR multi engined a/c have always shut down engines.....VC8 [Viscounts] shutting down in/out boards depending on Mark
Don't forget the DanAir Nord262, taxied in on two, shut down one on stand [the one by the door], taxied out on two...and took off...on two.
bb
Don't forget the DanAir Nord262, taxied in on two, shut down one on stand [the one by the door], taxied out on two...and took off...on two.
bb
Join Date: May 2000
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747 GE CF6: 4 minutes after start before takeoff. Depending on gross weight, can taxi with 2 or 3 engines running.
APU ~300 Kg/hr fuel; engine ~600-700 Kg/hr.
747 can either crossbleed start or run APU.
APU ~300 Kg/hr fuel; engine ~600-700 Kg/hr.
747 can either crossbleed start or run APU.
Join Date: Feb 2008
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I have just started flying A320.
There are lots and lots of details to this:
We can't do single engine taxi OUT above 75500kg
Or with contaminated taxiways.
We start no 1 (because it pressurizes green system which = brakes and n/w steering), turn Y ELEC Pump on,leave APU on and bleed on and taxi out. All checks such as flight control can't be done until we've started eng 2. Y Pump off, confirm sufficient bleed press and eng 2 lvr idle, then start no 2.
you need both engines running at idle or near idle for at least 2 mins before applying takeoff power, otherwise you get a CTR TNK FEEDG on the t/o roll.
For single engine AFTER landing, it's much simpler - make sure APU is on, switch Y ELEC pump on (avoids running PTU) then switch 2 off. Once on stand with off, switch Y pump off again. Must have engines near idle for 3 mins if reverse thrust was used - very rarely nowadays.
Yes - obviously you need APU whenever both ENG Generators aren't online.
see above. If the engines have been shutdown for more than two hours, they both need to run for at least 5 mins. So basically, they need to be well and truly started by the time you reach the holding point.
Depends how heavy a/c is and how long the taxi is - if it's a relatively light aircraft at somewhere like EHAM with really long, boring, tedious, arduous taxi then it could be a good idea- APU burns quite a bit less fuel than ENG1!
However, I do find th a/c quite a bit more cumbersome with only 1 eng when a/c is fairly heavy, and also I find that the procedures involved give you even more to do on the taxy out. i don't like doing it, but do at places like AMS or CDG. it's at PF's discretion.
should you need any more info, pm me. i'm happy to help.
1234
- What are the procedures for a single-engine taxi?
We can't do single engine taxi OUT above 75500kg
Or with contaminated taxiways.
We start no 1 (because it pressurizes green system which = brakes and n/w steering), turn Y ELEC Pump on,leave APU on and bleed on and taxi out. All checks such as flight control can't be done until we've started eng 2. Y Pump off, confirm sufficient bleed press and eng 2 lvr idle, then start no 2.
you need both engines running at idle or near idle for at least 2 mins before applying takeoff power, otherwise you get a CTR TNK FEEDG on the t/o roll.
For single engine AFTER landing, it's much simpler - make sure APU is on, switch Y ELEC pump on (avoids running PTU) then switch 2 off. Once on stand with off, switch Y pump off again. Must have engines near idle for 3 mins if reverse thrust was used - very rarely nowadays.
- Is the APU left on for the entire taxi?
- Is there a certain duration which engines must be spooled up for before they are TOGA/FLEX-rated?
- Does keeping the second engine off really save that much fuel considering the running of the APU and the additional thrust required to move the aircraft?
However, I do find th a/c quite a bit more cumbersome with only 1 eng when a/c is fairly heavy, and also I find that the procedures involved give you even more to do on the taxy out. i don't like doing it, but do at places like AMS or CDG. it's at PF's discretion.
should you need any more info, pm me. i'm happy to help.
1234
