When to start engines

I was wondering to make it realistic when do I start engine 1,2 while pushback? Etc.


You should do this once you finished pushback. Start engine 2 first, wait for it to get to 19% N1, then start engine 1


Start engine 2 after starting pushback then once stable, start engine 1. Sometimes conditions can be such that you should start them after pushback but that depends on the airline/airport operation procedures.

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From real life, they normally roll whatever engine we tell them immediately during push. Engine 1 or 2 depends on conditions as well as the airline SOP.


Yes usually I start the first one during pushback then the next one. In the real world from my experience it’s always initiated during pushback, not after.


Thanks everybody

I start Engine #2 during pushback. By the time I finish pushback, Engine #2 is at N1 19%. Then I start engine #1

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always start the right engine 1st then left.
in light to medium aircraft start the right engine while pushing back once you’ve cleared the gate completely and then the left one.
heavy jets start both their engines once the pushback is complete. as the pushback tug has just enough power to push those heavies. and even idle thrust from engine wont help their cause.

On my long haul flights on BA and Qatar it was started during pushback.

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well I haven’t had much flight in heavies. my most flight is a320 or 737. but only 2 occasion. and on both the engine started after pushback.
I also read an article somewhere about engine start after pushback and their reasoning.
It may be that it is common on certain airports where they have some old push back tug not powerful enough. and certain airports have Powerful tugs.

I don’t doubt that, I’m just stating that’s it’s not in all cases.

Airports have their own procedures and airlines I’m sure. No way to pinpoint one specific way I guess.

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yup. both the procedure is correct depending on what pilot choose. :)


I personally start engine 2 while pushing back and then start engine one once lined up on the taxiway I pushed to.

Depending on the airline really, they either start one or two engines during pushback. They almost NEVER start the engines once the pushback is finished, and sit on the apron for 3-5 minutes before taxiing, and blocking traffic. Especially considering almost all engines need a warm up time before they can really be active, this just gives you an even better reason to start your engines during pushback instead of after pushback. Happy flying!

When I fly an airbus I start engine 1 first then 2, if I’m flying a Boeing I start engine 2 then 1

Generally engine 2 is started first as most aircraft run primary electrical power from engine 2 outboard fuel tanks, for example the APU pneumatic power. For example the Airbus A320 family has 3 primary hydraulic systems yellow, green and blue. The yellow driven pump is controlled by engine 2 and in most SOP’s this is the case to start #2 first as more essential controls such as the parking brake and nose wheel steering are controlled by this reservoir.
Most aircraft run their APU generators from the left outboard tank, or left wing tank on the 737 series.
Therefore starting engine 1 first with already used fuel from the APU could create a minor fuel imbalance during flight due to extended APU use.

Another scenario is in the Dash 8 Q400 aircraft, sometimes the flight crew will start engine 1 first if a single engine taxi was initiated with the #1 engine off to help stabilize a minor imbalance.

So most of the time you’ll start your engines during pushback, there’s a few scenarios where you have to avoid this though. In older 737’s there’s something called a lock-out pin, this pin isolates hydraulic power to the nose wheel during pushback to avoid damage. The 777 I believe you have to avoid hydraulic power to one of the lines, I can’t remember which line that is but if pressurized during towing it will result in damage.

Long story short, generally engine 2 is started first on most aircraft like the 737 and A320.

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I start one but if the airport is really busy I taxi with one engine & start the other engine when I’m number 3 in line to take off :)

To add to this then when should engines be switched OFF

When you’re at the stand, turn your beacon light off when your engines are at 0% N1.

Sometimes during long taxi engine #1 is turned off as generally again that’s where the APU fuel is fed from which help prevent fuel imbalances, as I mentioned above some hydraulic and pneumatic components require a certain engine to work properly.
However you should ONLY taxi with 1 engine after landing as most SOP’s require an extended warm-up period before takeoff, and is not a good idea as a fuel imbalance might occur before takeoff.
Even after landing most SOP’s require the engine to cool for a certain amount of time before it is shut off to prevent shock cooling.

Depends on the aircraft size (strength of the engines). I start whilst I’m pushing back when I’m in a a320 for example, but start engines after push-back in b777 for example.