Airliners or jets in general, before takeoff checks?

Question

Just wondering, as a private pilot. Of course before taking off with a small aircraft, you do a run up, take the throttle to the firewall essentially and check the mags and carb heat, for example. Just wondering, for an airliner or even like a Lear or something, do they do anything similar? I used to work at an airport and don't really remember them doing any sort of a run up. How about a turboprop, like a Kingair or something?

Answer 1

No, turbine aircraft do not do a run up. They just start them and look at the gages, and if they are running okay at idle, they will run okay at takeoff power or more. There really aren't any magnetos to check, and most of the checks we do are at the gate before the engines are running. Of course we have before takeoff checklists, but they don't include running the engines. I mean, the engines are running, but we don't check that. We check to make sure everything is set up for takeoff, like the flight attendants being seated and the lights on and such like that. If you see a turboprop or a jet running up, it's the mechanics doing some kind of test run on the engine. The pilots just get ready and go.



The funny part is that we turn the ignition off on jet engines and they keep running. They are self-sustaining. Pretty funny when you take up a piston pilot and tell him you are going to shut off the ignition! lol....



Hope this helps you.

Answer 2

Jets don't do run-ups as there is no jet equivalent of a mag check. An airline's before take-off check has many of the same things you would do when flying a single engine Cessna (e.g. transponder set, radios set, flaps take-off position, etc) but nothing really having to do with the engines other than perhaps making sure they are running and the gauges are all green.



The only time when I jet might do a "run-up" is when starting the other engine. Airlines will frequently taxi out on one engine only and start the other one, off of air from the running engine, when they are closer to take-off. This would entail running the engine up to a fairly high setting but only because it needs to generate enough air to start the other engine... not to test that the engine is working properly.

Answer 3

I know of no airplane that has NO predeparture checklist.



On an airliner, depending on the airplane, the checklists can be fairly simple or quite complex, generally depending on the presence or absence of automation.



Older technology airplanes (DC9 MD80, early 737) have few automated systems, so there are a lot of switches to check and readings to confirm, so their checklists are "busy" and long.



FYI, our MD80 has about 15 items that are checked in the gate, and about another 10 that are checked after the engines are running and before takeoff. Each airline develops its own checklists, using the manufacturer's checklists as a guide.



Newer technology airplanes (B757, 767, 777, Airbus) are more automated and their checklists are much simpler. A 757 checklist may have fewer than a dozen items from "cold dark airplane" to "ready for takeoff"



No runup is done, but a "health check" is done as power is advanced for takeoff. An engine power setting is calculated for takeoff, and if the engine meets the required power without exceeding temperature or speed limitations, the takeoff continues. If not, the takeoff is aborted and the reason determined.



A full power engine run is done periodically by maintenance folks to confirm the engine's health.

Answer 4

In JET airplanes - any jets - the shortest before takeoff check list is -

TRIMS - FLAPS - SPOILERS - we call that "The 3 Killers" -

Your airplane can be a F-16 or a A-380 -

You will crash if one of the 3 killers is not properly set for takeoff -



You can line-up and wait - then do the 3 killers and forget ALL check lists -

Forgetting the landing lights will not make you crash -

Forgetting ignition will not make you crash -

Forgetting the transponder will not make you crash -

Forgetting the compass alignment will not make you crash -

Forgetting the altimeter setting will not make you crash - etc...

But forgetting one of the three killers is guarantee to make you crash -



Every time I lined-up in my career - "I did" the 3 killers -

Whether I did check lists ok or not did not matter -

It saved my life a few times - flaps where not set - or trim not set -



In a propeller airplane many more things need to be checked -

So does not apply to your Cessna or Piper -

Answer 5

I have found that as the complexity of the aircraft increases, the checklists decrease. As I recall there were six items on the 747-400 take-off checklist. (Flaps set for take off? Trim set?)



Granted, many of the settings on these aircraft are included in "flows" that involve multiple checks and re-checks before even pushing the airplane back from the gate.

Answer 6

C130s run up for about 5 to 10 minutes before they taxi out.