No more runups

And your reasoning is?

I generally only do a "full" preflight before the first flight of the day, but I always do a walk around and look for anything out of place, and I always check the oil and do a runup.

That's assuming the airplane has been in my control the whole time. Somebody else flies it, it gets a "full" preflight again.

I've caught a mag failure in the middle of a day doing my run-up.
 
TMetzinger said:
I generally only do a "full" preflight before the first flight of the day, but I always do a walk around and look for anything out of place, and I always check the oil and do a runup.
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That's how I've always done it, too, but I've had to stop checking the oil between short flights, now that I live on the Texas gulf coast. After burning my hand a few times on the dipstick handle I realized that I wasn't flying in the cooler latitudes any more... :D
 
TMetzinger said:
And your reasoning is?

I generally only do a "full" preflight before the first flight of the day, but I always do a walk around and look for anything out of place, and I always check the oil and do a runup.

That's assuming the airplane has been in my control the whole time. Somebody else flies it, it gets a "full" preflight again.

I've caught a mag failure in the middle of a day doing my run-up.
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Same for me. I at least do a walk around, check the oil and do a full run up. Never know what might decide to quit working.
 
And this in total disrgard of the 10% of accidents that might be due to mechanical? A sacrilege, I tell you, an abosulte sacrilege.

What do you guys use instead of a Hail Mary?
 
Glad to hear it.

Runups are one of those rather useless yet very pervasive "traditions" in aviation that people do without thinking about why. I don't do a runup ever, not even once a day as there is no point.

-Felix
 
sba55 said:
Glad to hear it.

Runups are one of those rather useless yet very pervasive "traditions" in aviation that people do without thinking about why. I don't do a runup ever, not even once a day as there is no point.

-Felix
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I agree. I stopped checking the oil and sumping the gas too. After all it is a rental and the guy before me took care of it. Heck, I don't even bother turning the radios or nav lights on...who wants to be troubled with details that improve safety.

Sorry for the sarcasm, but really, is the 40 seconds to do a runup really a huge inconvenience? I only have 100 hours and have turned back on two occasions due to mag test failures.
 
Bob Noel said:
May I ask why?
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I do a pretty thorough pre-flight before the first flight of the day. My cowling provides easy access and I can inspect the engine for fuel, oil and exhaust leaks. In the aircraft, I follow my check list and do a runup with a Magneto check and cycle my prop once. For further flights in the day, I check the oil and do a quick walk around. I follow my check list but don't do a runup for subsequent flight legs. I figure, I just did a several hour long magneto check and the prop cycled on the last takeoff and cruise.

I don't see much value in the ground magneto check as it doesn't point much out. A better check is a lean of peak magneto check in flight as it will point out minor discrepancies in the electrical system, like a weak plug, long before it will show up on a ground runup.
 
John Collins said:
I do a pretty thorough pre-flight before the first flight of the day. My cowling provides easy access and I can inspect the engine for fuel, oil and exhaust leaks. In the aircraft, I follow my check list and do a runup with a Magneto check and cycle my prop once. For further flights in the day, I check the oil and do a quick walk around. I follow my check list but don't do a runup for subsequent flight legs. I figure, I just did a several hour long magneto check and the prop cycled on the last takeoff and cruise.

I don't see much value in the ground magneto check as it doesn't point much out. A better check is a lean of peak magneto check in flight as it will point out minor discrepancies in the electrical system, like a weak plug, long before it will show up on a ground runup.
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I follow your reasoning, and IF the airplane has good engine monitoring, then I might be more inclined to consider dumping the mag check.

But I've had mags fail in flight and not notice - at cruise power without a GEM or JPM or G1000 to see the bar graph suddenly change it's just not that big a difference with one mag versus two. But I caught it on the next mag check.
 
kevin7500 said:
I agree. I stopped checking the oil and sumping the gas too. After all it is a rental and the guy before me took care of it. Heck, I don't even bother turning the radios or nav lights on...who wants to be troubled with details that improve safety.

Sorry for the sarcasm, but really, is the 40 seconds to do a runup really a huge inconvenience? I only have 100 hours and have turned back on two occasions due to mag test failures.
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No, and it's not about inconvenience. It's about what makes sense.

A runup doesn't make sense, and all it accomplishes is maybe put a chip or two in your prop. That's it.

As for what Tim says - engine instrumentation doesn't have anything to do with this. If you do a runup on the ground, it's very unlikely that you would have caught the mag issue. If you want to do that, do a mag check in the air. It's certainly fine to turn off mag 1/2 on the ground to make sure that they are working at all.

-Felix
 
sba55 said:
No, and it's not about inconvenience. It's about what makes sense.

A runup doesn't make sense, and all it accomplishes is maybe put a chip or two in your prop. That's it.

As for what Tim says - engine instrumentation doesn't have anything to do with this. If you do a runup on the ground, it's very unlikely that you would have caught the mag issue. If you want to do that, do a mag check in the air. It's certainly fine to turn off mag 1/2 on the ground to make sure that they are working at all.

-Felix
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..and since you're generally flying a rental how exactly do you expect to know if an in-flight mag-check was done before the flight? I know more or less nothing about the previous flight - or if they encountered a problem. Some people are terrible about reporting or noticing much of any problem.

Sorry but I've found problems on rentals during a run-up...and as a result...will continue to do them.
 
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John Collins said:
I don't see much value in the ground magneto check as it doesn't point much out. A better check is a lean of peak magneto check in flight as it will point out minor discrepancies in the electrical system, like a weak plug, long before it will show up on a ground runup.
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I agree 150%. I do a LOP mag check instead of the full rich mag check. a leaned out mag check is far far more diagnostic. I still do em out of habit while taxing with at least one good cycle of the prop.

When I got checked out in a twin once the Chief P...muttered something like...f'n waste of time. really though?


I too have found a mag that gave up the ghost on a multi leg day..
 
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Having caught a detached prop cable on a twin on a run-up, not to mention any number of bad plugs, I'll keep doin' 'em.
 
So ya don't wanna do a full power turn up around here on yer normally aspirated engine? Not really a good idea but feel free to do whatever you like. Just advise yer passengers of the consequences, eh?

Hint: "here" is a density altitude above 3000 feet.
 
Here's why I do them: it is true that a ground run-up and mag check won't reveal every possible impending failure, nor will it prevent them.

It is also true that a ground run-up and mag check should not be necessary if a number of other things have been done maintenance/operation-wise.

But if something bad is waiting to happen when I apply full power, I'd rather find out while on the ramp holding the brakes than when I'm committed to the takeoff roll.

It's like a control check, sumping fuel, or even a walkaround, in many cases- you shouldn't need to do it, but a failure to do so has killed a number of people, or at least cost them a lot of trouble and expense.
 
There have been a number of times I have caught that plugs have fouled and the engine wouldn't have made full power... And, once on a runup the engine wouldn't clear - I thought it was plugs and had worked to clear them... it kept dropping significantly etc - we went back in, pulled the cowling and poof* a lead to one of the plugs was loose/nearly off. Tightened it checked everything else... flew home. Taking off at 7500 ft DA w/ that situation in an underpowered to begin with C-152 to fly across the tullies would have been a bad thing.
I'll continue to do runups, thanks
 
Ron Levy said:
Having caught a detached prop cable on a twin on a run-up, not to mention any number of bad plugs, I'll keep doin' 'em.
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Caught a bad plug one morning on run-up. And I was the last person to fly the plane (the evening before). And I've also grounded another plane in the club due to a failure during the run-up. With my son in the right seat. I'll keep doing them, too.
 
Had a bad mag once, but it only showed up when hot. First runup of the day wasn't hot enough, detected it when running it up to come home.

Ron Wanttaja
 
OK, have you seen the new V-4 Honda sportbike???
 
jesse said:
..and since you're generally flying a rental how exactly do you expect to know if an in-flight mag-check was done before the flight? I know more or less nothing about the previous flight - or if they encountered a problem. Some people are terrible about reporting or noticing much of any problem.

Sorry but I've found problems on rentals during a run-up...and as a result...will continue to do them.
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I don't generally fly rentals (except a 152 from time to time), but if I weren't sure about the condition of the engine, a runup wouldn't tell me anything useful anyways.

Like I said, it's perfectly fine and a good idea to check that both mags are working. Besides that, increasing power on the ground causes excess heat, potential prop damage, and no useful information besides what you might find when powering up on the runway.

Edit: Just like engine instrumentation isn't the issue here, in-air mag checks aren't the issue either. Both are useful, of course, but they're not directly related to this issue. But I give up .... this kind of reasoning is just too childish. McDonalds feeds me just fine; so why would I try something else even if it's better. :O

Glad at least OP has figured it out!
 
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Richard said:
Why stop there? Why not aspire to be the pilot who kicks the tares, lights the fares?
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Here in the Northeast was a multi auto dealership owner -- and his twin-engined plane which carried him between several states until the plane went down, fatally for him. His preflight was to observe the fuel gauges, start the engines, observe the other gauges. If oil pressure was in the green, good to go. During the final flight one engine failed. Information is that he feathered the wrong prop and the plane went down. Upon the ensuing investigation it was determined that the failed engine was bone dry of oil. Lax preflight?

HR
 
Preflight first flight, walk around each stop. Mag check every take off. sometimes it's a rolling mag ck.
 
sba55 said:
I don't generally fly rentals (except a 152 from time to time), but if I weren't sure about the condition of the engine, a runup wouldn't tell me anything useful anyways.!
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Well. Everytime I've seen you -- you've been flying a rental or a club or an airplane other people fly as well. Since you don't know what happened on the previous flight I wouldn't put too much trust in them diagnosing much.
 
I have caught a broken prop cable and a bad mag doing a run up between flights. I'll continue doing them before each flight.
 
Apparently some people think that a mechanical failure will only occur during
the dark of the night. I wonder why they think nothing breaks when the
sun is shining.
 
Clark1961 said:
So ya don't wanna do a full power turn up around here on yer normally aspirated engine? Not really a good idea but feel free to do whatever you like. Just advise yer passengers of the consequences, eh?

Hint: "here" is a density altitude above 3000 feet.
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"Here" is a density altitude of 6000' on a cold day. And I agree with you completely.

I might abbreviate a run-up (maybe I won't exercise the prop) but even with a full run-up (which, here, included leaving for best power on takeoff) the whole thing takes about 30 seconds.

Let's see... 30 seconds taken away from my life vs even a statistically small chance of missing something. My cost-benefit calculation says do it. YRMV.

btw, as I recall there is at least one NTSB case involving an enforcement action based on failure to perform a pre-takeoff checklist item when an incident or accident resulted fro, the failure of the unchecked item. I think is was a mag check
 
I do full runup each flight after parking and being out of sight. 99% of the time if I catch anything, it's going to be some fouling, easily corrected with some mixture/throttle play.

IMHO having clear plugs will give me as much power as I can expect -- fouled plugs will provide less. On takeoff I want as much power as I can get.

That said, I'm not a fiddler. I roll up, do the check, and ready to go in less than 30 seconds (Don't wait until you're stopped to do "Free and Correct" -- catch that, lights, and brake effectiveness somewhere between the hangar and the hold line).

Lights, Camera, Action and go.

These are air cooled engines, and IMHO sitting at idle or 1500 RPM for 15 minutes is just plain pointless.
 
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Ted DuPuis said:
You mean he's been lying about those airplanes he says he's owned? Say it isn't so, I always thought Felix was an honest individual. :D
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:rofl::rofl::rofl::rofl:

Ted DuPuis said:
Catching a bad mag, fowled plug, etc. before takeoff is important, doubly so in a single. In my case, knowing that the props will feather is also important.

It doesn't matter whether or not you know the plane. Planes that you know can still break, and will frequently do so.
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:thumbsup:
 
I'm really curious what the reasoning is behind the OP's statement... And regardless, I will continue to do run ups and pre-flights. I've have experience with a perfectly good Taylorcraft that had $20K worth of damage done to it by another pilot who didn't do the pre-flight and missed an item that should've grounded the airplane for no more than a week. Instead, the item broke...

Ryan
 
Fiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiish!
 
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