Do run-ups work?

cocolos

cocolos

Pre-takeoff checklist
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cocolos
I'm just curious how effective they are and if there are things we can add?

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Considering I wouldn't have discovered my oil cooler ruptured without doing one, and my engine would have seized up somewhere over the Appalachians, no they are worthless and don't do anything to add to safety.
 
After I installed an autopilot I went to test fly it. Mag check revealed the engine would completely die on one of the mags. Turned out the frame of the autopilot was in contact with one of the ignition switch contacts behind the panel and would ground the one mag causing it to fail.

Have had numerous occasions with rough idle at mag check.
 
I had fouled plugs and busted carb heat cable that were discovered during two separate runups within the past two years...so yes, they are effective.
 
If you mean running the engine up to ensure it runs smooth and isn't stumbling then yes. If you mean checking to make sure you do in fact have 2 working magneto ignition systems, then yes. if you mean in terms of burning off fouled plugs, then sometimes. The only thing I can think of adding is agressive leaning on the ground and minimizing time at very low/idle RPM when not moving (no load on prop).
 
I wouldn't take off without doing a runup. The worst I've caught have been some fouled mags in some of the flight school 152s but haven't had that issue in either club 172s. Full power and leaning out solved the mag problem every time.

I would much rather catch some severe issue during runup than in the air. Obviously.
 
Had an entire plug wire fall off that showed no signs of trouble at all during taxi (would have with an engine monitor of course), but clearly was there at run up.
 
In six years I've caught two problems that I was happier to find out about on the ground rather than in the air.
 
Yes run ups work. I would have taken off with a bad mag if I didn't do a run up.
 
Yes, but you can still have a bad mag or something else wrong after a normal runup.
 
Runups are a real pain. They have caused me to postpone a couple of flights.
 
I'd never fly a piston without doing one
 
They certainly work. As to what could one add, that's why I like making my own checklists, it gives me time to sit in the plane and review procedures in the plane and consider just that. Typically though unless there is some major mod, the book procedure is sufficient to cover what's needed.
 
Definately ,if you like to gamble,just skip that part of the checklist.
 
PA-32-301R. I have switching tanks as part of my run-up checklist. Vibration had loosened the screws holding down the shroud covering the tank selector, which is a off-left-right valve located deep under the panel in the footwell. Before my run-up I switched tanks and the engine died! It took a few restart - cough - stall cycles before I figured it out.

The thumb lock to prevent turning the valve to 'OFF' is fixed to the shroud which had moved just enough to prevent the thumb lock from engaging the valve handle. :hairraise:

So Yes Runups catch items which can be detrimental to continued flight!

-Skip
 
I've caught stuff on a run up before, so yes they work.

I'm also a daily run up guy, for working planes I'll do one runout at the start of the day, but not before every takeoff.
 
James331 said:
I've caught stuff on a run up before, so yes they work.

I'm also a daily run up guy, for working planes I'll do one runout at the start of the day, but not before every takeoff.
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I'll usually do a mag check on the roll at least on quick turns to make sure I still have them all. I have lost mags mid day/route before.
 
James331 said:
I've caught stuff on a run up before, so yes they work.

I'm also a daily run up guy, for working planes I'll do one runout at the start of the day, but not before every takeoff.
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Every flight for me. I've lost a mag on the second flight of the day.
 
I've found problems on runups, both preflight and post flight. I've also had an auto feather system fail between the time I checked it on the runup and when I armed it for takeoff...and no, that's not saying a runup is ineffective. It's saying any tme you flip a switch, check to see that it's having the desired effect.
 
fouled plugs, bad mags, clogged injectors, bad prop seals, other than that, they haven't done much for me
 
A run up has never detected a weight and balance issue so I think they probably don't work. Boycott the run up!!
 
James331 said:
I've caught stuff on a run up before, so yes they work.

I'm also a daily run up guy, for working planes I'll do one runout at the start of the day, but not before every takeoff.
Click to expand...

I do the same. On the piston engine(s) after landing and taxying to parking I will turn each mag off to make sure I still have both.

Full power runups may scare passengers, I won't do a run up with patients onboard unless absolutely necessary. Do the run up before passengers get to the airport.
 
Do run-ups work?

I learned the answer to that question before I knew what a run-up was:lol:.

My first flight lesson was terminated and we taxied the 172 back to the flight school, after discovering a bad mag as my instructor walked me through the procedure. There were no other planes available, so that was it for the day. So my first logbook entry was .3 or .4:rofl:
 
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To the OP. -Always -you're just going to launch an hope everything is OK? Gust lock removed? Fuel lines unblocked?
I don't care how many times i've flown Nxxx; i'm going to treat it like stranger.
The Pre Takeoff Checklist (i.e. Runups) is written by the OEM & approved by the FAA.
That makes it mandatory. i.e; you skip, you bust the FARs. You never know who is watching.
Aviation is only as safe as we continue to make it.
 
neilki said:
To the OP. -Always -you're just going to launch an hope everything is OK? Gust lock removed? Fuel lines unblocked?
I don't care how many times i've flown Nxxx; i'm going to treat it like stranger.
The Pre Takeoff Checklist (i.e. Runups) is written by the OEM & approved by the FAA.
That makes it mandatory. i.e; you skip, you bust the FARs. You never know who is watching.
Aviation is only as safe as we continue to make it.
Click to expand...

What if your plane doesn't have a pre-takeoff checklist because it was made before the days of lawyers being able to advertise?

Also which FAR am I busting if I skip it?
 
SkyDog58 said:
I have performed numerous runups on turbines.
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@SkyDog58 Every time we start the takeoff run in an airliner we run the engines up. Only once they have accelerated symmetrically without any abnormal indications do we set Take Off power.
 
EdFred said:
What if your plane doesn't have a pre-takeoff checklist because it was made before the days of lawyers being able to advertise?

Also which FAR am I busting if I skip it?
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I'n no lawyer, but 91.103 would be a place to start.
 
neilki said:
I'n no lawyer, but 91.103 would be a place to start.
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Good thing you aren't a lawyer, because 103 says nothing about run-ups.

(b) For any flight, runway lengths at airports of intended use, and the following takeoff and landing distance information:
(1) For civil aircraft for which an approved Airplane or Rotorcraft Flight Manual containing takeoff and landing distance data is required, the takeoff and landing distance data contained therein; and
(2) For civil aircraft other than those specified in paragraph (b)(1) of this section, other reliable information appropriate to the aircraft, relating to aircraft performance under expected values of airport elevation and runway slope, aircraft gross weight, and wind and temperature.
Click to expand...
 
EdFred said:
Good thing you aren't a lawyer, because 103 says nothing about run-ups.
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I'm not getting into a public scrap with you when you're advocating poor decisions. Other pilots read this and the answer shouldnt be a matter of debate or opinion.

CFR 91.103 starts with: Each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight.

If you think you're OK skipping an approved checklist and still complying with that; i suggest you find a lawyer.
 
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