Airline Question

Wm226

Well-Known Member
I have a question that has been bugging me the entire day. Do commercial airliners do runups?
 
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I have a question that has been bugging me the entire day. Do commercial airliners do runups?

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Nope. At least none I fly.
 
Not really a run up but every airliner I have been in has a "First flight of day" checklist, which is run in the morning and every time the plane sits for more than 4 hours.

The turboprops actually do a "run up" but that is mostly to check prop things, like autofeather, governors, etc.
 
I flew on United from SFO to DEN in december and during taxi I saw the ailerons and flaps moving, and it appeared as the crew was checking the operation of the flight controls. They may not do a run-up per se, but they may do some things we typically do during a runup while they taxi. I highly doubt they'd do a mag check though.
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We have first flight items (deice boot test, ice protection test, etc.) that are done every morning, and a propeller feathering system check (P3 switch test) done every Monday morning. We do the VOR check and max power takeoff the first flight every Monday as well.
 
There are a few checks and tests that go on before every flight, but because there are two of us they always get done on the taxi out. Some airplanes have more checks than others. For example the autofeather system is checked before every flight on the Brasilia. Most airlines do a flight control check on the taxi out.

So, no, not necessarily a "pull off the side of the run-up area," but there are things that get done before takeoff.
 
Not an airline pilot, but in my studies of turbine engines, I've read that a runup as you're thinking of it isn't necessary because the greatest stress imparted on them in the course of a day is the simple act of cranking 'em up--particularly for engines without FADEC systems (Full-authority digital engine control, do a search). Has to do with hot-section temperatures and the potential for heat damage before sufficient airflow through the engine is established. And like FlyChi said, turboprop runups are to check stuff other than proper engine operation.
 
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Most airlines do a flight control check on the taxi out.

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How does a pilot determine if the rudder and elevator are working on an airliner?? Or for that matter, can they really see the alierons?

MF
 
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How does a pilot determine if the rudder and elevator are working on an airliner?? Or for that matter, can they really see the alierons?


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We have a flight control page on our ECAM display (pretty tv picture tube on the forward instrument panel
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) that shows graphically the primary flight controls and their movement. The spoilers can also be displayed on the ECAM.
 
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Do commercial airliners do runups?



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Not like you do in piston engine aircraft. System checks are performed at the gate. Flight control checks are performed while taxiing out. Jets are normally considered to be ready for departure when they reach the end of the runway. We have to make sure that the engine oil temp has warmed sufficiently (50C) but that's rarely a problem by the time you get to the rwy. If engine anti-ice is used we do a small engine runup while holding in position on the rwy prior to the application of takeoff power.
 
The only "run-up" similar to a piston that we do is a 20 second run at 60% N1 to clear out any residual fluids after de-icing just prior to takeoff. Flight control check is accomplished using the synoptic page on the EICAS.
 
We just ensure the controls aren't binding. I also look out my window to ensure the ailerons are properly rigged and moving. We can see the outboard section of our wings... in most airliners you cannot see much.
 
The only runup that we do is when using one engine to start the other (cross bleed start). This is only done when the APU is deferred.

We check the flight controls prior to each flight. Deice systems, flaps, and spoilers are first flight items.
 
For the first flight of the day, The ERJ needs to do a "runup" to 83%n2 for an Ice protection test. This takes approx 30 seconds.
 
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