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Glory Aulik
06-15-2016, 07:31 AM
Below is the new bi-weekly question:

If you land and turn off your engine for just 5 minutes, would you still do your full run-up before takeoff? What if you did not shut down at all? Would you still do your full run-up and why?

Vision401
06-15-2016, 11:03 AM
In a rental aircraft:
If no passenger, no. It would still be a risk.
If I had a passenger on board, yes. It would be an opportunity to observe magneto performance.

In my aircraft (New Corvair conversion with e-points, single set of spark plugs), no in both cases. A Run-up would not tell me anything I didn't already know.

dougbush
06-16-2016, 01:07 AM
What's the difference between a run-up and a full run-up?

Frank Giger
06-16-2016, 05:23 AM
In a standard aircraft, do the run up and control check.

Like Vision, my aircraft is single ignition and plugs (and automatic carb heat), so for me it's just a control check.

martymayes
06-16-2016, 09:36 AM
What's the difference between a run-up and a full run-up?

A full run-up would include everything a run-up does not.... :cool:

rwanttaja
06-16-2016, 09:54 AM
What's the difference between a run-up and a full run-up?
And what's the difference from a half-full run-up? :-)

Many people use the term "run-up" to denote all the checks done just prior to entering the runway for takeoff. That would include mag/carb heat checks, control checks, cabin checks, flicking the last boogers out the window, etc.

Owning a simple airplane like a Fly Baby reduces the number of items to take care of. No trim to set, no windows or doors to check, verify radio and transponder (which is perma-1200) with a glance. I perform mag check due to the possibility plugs fouled on the last landing (hasn't happened yet), a carb heat check to make sure the engine's clear, a controls-free-and-clear check to make sure they're, well, free and clear (had a case happened where the ailerons developed an obstruction during a fuel stop), and make sure the goggles are down and snug. Doesn't take that long.

I've skipped the runup in rare cases, but I monitor the engine closely when powering-up for takeoff.

Ron Wanttaja

wyoranch
06-16-2016, 11:22 AM
I guess I am a sissy, given the opportunity to check the condition of my aircraft I take it. Alas I did violate my rule when I was instructing, my home airport did not allow touch and goes so it was a full stop with some review before the next take off, never did a run up (1/4, 1/2, 3/4, partial OR full) between those. But my hard rule is ... Shut down, run up........ no exceptions. Heck I usually give the plane a walk around, never no when an errant fuel truck or meteorite may have hit my plane.
Rick
In the interest of full disclosure about the practice with students, I have had 3 major failures in my life
1)Total destruction of an engine in the pattern (My student cried the whole way to the runway, don't blame him, but to his credit went and got another rental and continued on, I was very proud of him)
2)Hydraulic loss in a Navajo (transition training the new owner)(deal fell through... imagine that)
3)A MAG failure on climb out while we were doing to/lndgs. Don't know if a 'run up' would have helped.....
My point is that a 'run up' probably would not have found any of these items, but I still hold to my policy.

FlyingRon
06-17-2016, 06:44 AM
I've caught mag and plug problems at the runup though my most onerous mag problems NEVER showed up in a preflight mag check (you could do 100 mag checks at various power settings and for some reason as soon as you got 400' in the air they would start misfiring).

I assume run up means any preflight check you do at a power setting other than near idle. On my plane the prop cycle and mag checks are the only things that need be done at that power setting. I will do the mag check pretty much on anytime after shutdown.

Mike M
06-18-2016, 08:56 AM
Way way back in business school they taught the FIFO and FIFI inventory methods.

FIFO equates to "it Flew In, it'll Fly Out."

FIFI equates to "F--k It, Fly It."

Neither is as good as a runup.

Byron J. Covey
06-19-2016, 06:58 AM
Below is the new bi-weekly question:

If you land and turn off your engine for just 5 minutes, would you still do your full run-up before takeoff? What if you did not shut down at all? Would you still do your full run-up and why?

I always do a run-up before the first takeoff after engine start.

After 5 minutes idle time on the ground after landing, I would do a run-up under certain conditions, such as high density altitude to lean for maximum power, for a relatively short ruway, or with passengers. Otherwise, I monitor the engine to verify that it smoothly reaches full power early in the takeoff run.


BJC

Bob Dingley
06-19-2016, 09:20 AM
Lets parse the question. "Run up" is kind of vague. Lets ask "Do you run the full checklist or the alternate checklist?" Example: the kid brother of a friend made an intermediate stop 30 miles short of destination in a Barron to drop off one passenger. He was in a big hurry and no checklist. He made a fast turn onto the active while pushing the throttles open. Intersection T.O. Rotated early due to less than full runway. It was then that he realized he was still on AUX tanks (they were pretty low). Number one quit while rotating. And everyone here knows why. Whats amazing is everyone lived. Barron destroyed.

Jim Hann
06-19-2016, 09:56 PM
Below is the new bi-weekly question:

If you land and turn off your engine for just 5 minutes, would you still do your full run-up before takeoff? What if you did not shut down at all? Would you still do your full run-up and why?

Spent two years flying Barons and Aerostars in Part 135 frieght. Did a run up at the beginning of the night and if I changed airplanes during the night. Otherwise, didn't bother again. Now, this does not mean I didn't use the checklist. Checklist is used every time! I do basically the same thing with my Pacer.

If I add gas, yes I check for water. Again, checklist is used every time!

Jim
(Yep, I'm expecting flames on this one!)

Mike M
06-20-2016, 07:19 AM
Spent two years flying Barons and Aerostars in Part 135 frieght. Did a run up at the beginning of the night and if I changed airplanes during the night. Otherwise, didn't bother again. Now, this does not mean I didn't use the checklist. Checklist is used every time! I do basically the same thing with my Pacer.

If I add gas, yes I check for water. Again, checklist is used every time!

Jim
(Yep, I'm expecting flames on this one!)

You may get flamed, but you were doing what most working professional aviators do. Risk management and making a living. I did it too.

Jim Hann
06-26-2016, 05:57 PM
You may get flamed, but you were doing what most working professional aviators do. Risk management and making a living. I did it too.
Thanks, I only had two single engine landings in those years and no single engine takeoffs. Both shutdowns were control cable failures (one each throttle and mixture) not engine problems. I loved both airplanes but I don't miss making a living in recips!

Jim

1600vw
06-27-2016, 05:45 AM
Last year this happened to a crop duster in our area.

He was out working all day. He had come in to fill up with chemicals around 10 times. On his last fill up he turns and burns. As he gets passed the half way point he is not making speed. He starts dumping. He lifts off right at the end of the runway. But he is just inches over the corn. He is still dumping. He gets to the tree line and must turn for he can not get over the tree's. He spins her in and rolls her into a ball. This pilot wrote an article about this accident.

He said she would not make full power. Well she was running full power for it was a turbine, but something happened to the adjustable prop. It was not adjusting and he could not get any speed out of her. When I heard and saw this airplane in a ball, I wondered if he ever did full power run up's or did he always turn and burn so to speak.

I happened to drive by this man's place and saw this airplane in a ball. I was with an A&P friend who is also a PP. He took the number down or what we could see of it and he found this article the pilot wrote about this accident. He called me and read it to me and that was what he wrote or how he explained what happened. The airplane was a ball, but the cockpit was in tact and he did not get hurt. Those things are built like tanks I tell you.

Jim Hann
07-07-2016, 11:44 AM
... I wondered if he ever did full power run up's or did he always turn and burn so to speak.
Do you have a way to find the NTSB report on this accident? I'd love to know if he had even shut down or if he hot loaded.

After 19 years of flying turbines, both jet and turboprop, I can say I have only done a "full power" run up once or twice and I know for sure one of them wasn't when I was going flying. Depending on the system, you may not find a fault in a controllable/constant speed propeller during a run up. On the Garrett TPE331-14 (turboprop) powered airliner I flew we were required to do a full power takeoff once a day, usually the first takeoff of the day.

Only once did I not make torque, and we ended up canceling the revenue flight and ferrying the airplane back to the hub for maintenance. Why? Because we still had enough power to get a ferry permit, IIRC (its been 17 years) we made 87% of the 96% or so target torque. Yes, like a turbocharged piston we didn't "firewall" it.

Another problem a different day. Engines at 100% RPM, rolled on the runway mid afternoon for the next takeoff (had flown a couple legs in the same airplane) and we could only get 17% torque at 100% RPM. Yep, we left the airplane there and deadheaded out, she was broke hard. New fuel control and a complete rerigging of the power controls and she was fine.

My point is that a "full power" run up means different things on different airplanes. Turbines aren't harder, actually they are MUCH easier, but they are different.

Never did a full power run up on a jet.

I do a normal run up on my Pacer first flight of the day and when I'm concerned (usually that means I've left the airplane unattended, like eating lunch or taking a nap in the lounge.)

Lrrryo
08-02-2016, 12:13 PM
My point is that a "full power" run up means different things on different airplanes. Turbines aren't harder, actually they are MUCH easier, but they are different.

=====


Jim,
I never do a full power runup on any plane unless specifically required for maintenance which is rare. It's hard on the engine and picks up a lot of dirt.

As for a piston sunup, I do ONE the first flight of the day and only interested in two things..... the props will feather and the mag is not totally dead. Overall, ground run ups aren't a really good check. Prior to landing I do a LOP high power mag check, which is probably the best check for the mags.

As for a checklist and flows, I could argue to do them religiously. And there's MANY parameters that will keep one safe. A power check on the initial roll is in order.... getting the power desired and the performance. We time all takeoffs so we know if power is an issue at a point, and if the runway is short, there's an abort point set in advance.

Lots of ways to do it.

martymayes
08-02-2016, 01:51 PM
On his last fill up he turns and burns. As he gets passed the half way point he is not making speed. He starts dumping. He lifts off right at the end of the runway.

My question to the pilot would be "Did you ever consider aborting the takeoff?"

Lrrryo
08-03-2016, 08:09 AM
My question to the pilot would be "Did you ever consider aborting the takeoff?"

ABSOLUTELY!
I could argue to have and abort point on every takeoff. Whatever you call it and define it, it should be a point at which you should continue or go. Of course, if it's a single engine that point may be long after takeoff.

One should also have "checks" during the takeoff roll.... engine parameters, acceleration, speed check, etc., and at any point if those are not up to normal, an abort should be executed. And, if it's a short field, there should be a point on the runway where you assure that you have the performance to continue. I could argue to have 80% of the speed at the halfway point.

pilotben1986
08-25-2016, 10:07 AM
Run-up's are at the discretion of the PIC.
Some pilot perform their run-up at this first flight of the day, some do it prior to shutdown for any last minute write ups, some do it every leg, and of course there are always those pilot out there who just neglect to do it at all or ever. Yes there are checklist in place but there is no set limitation to how many times you need to do a run-up. If it makes you feel comfortable and more safe then by all means do it as often as you like. I think though with time you will get to know your aircraft and yourself as a pilot you will develop a good "feel" and say "you know my aircraft has had some engine trouble in the past I think I will run-up a couple times today" or "I have a pretty reliable engine on my aircraft and have never had a problem I feel COMFORTABLE with a run-up on the first flight of the day."

Mayhemxpc
08-25-2016, 02:34 PM
When I am giving a flight review or a check-ride (CAP) I always ask if the pilot calculated take-off distance for today. Sometimes they did, more often I get a response like, "We have 6000 feet of runway, surely that is enough." My response -- and my reason for asking -- is, if you know that on that particular day at that particular loading, that the airplane should reach Vr at 800 feet and you pass the aim point markers or VASI lights but you are not yet seeing Vr, it is probably time to abort the takeoff -- while you still have 4 or 5 thousand feet to stop safely. (Shorter runways have different considerations, but the basic idea remains the same -- do you have enough to take off? To stop? When do you make the decision and what will happen next?) Multi-engine thinking for single engine pilots.

Question for flight reviews: What would cause you to abort the takeoff?

Lrrryo
08-26-2016, 06:12 PM
When I am giving a flight review or a check-ride (CAP) I always ask if the pilot calculated take-off distance for today. Sometimes they did, more often I get a response like, "We have 6000 feet of runway, surely that is enough." My response -- and my reason for asking -- is, if you know that on that particular day at that particular loading, that the airplane should reach Vr at 800 feet and you pass the aim point markers or VASI lights but you are not yet seeing Vr, it is probably time to abort the takeoff -- while you still have 4 or 5 thousand feet to stop safely. (Shorter runways have different considerations, but the basic idea remains the same -- do you have enough to take off? To stop? When do you make the decision and what will happen next?) Multi-engine thinking for single engine pilots.

Question for flight reviews: What would cause you to abort the takeoff?

Chris,

Good points but one familiar with their aircraft really doesn't need a take off calculation it parameters are predictable, with a good margin. Example would be a 172 with 2 people, half fuel, standard temp, no gusts, ice or issues, on a 3500 ft strip, there's just no need to do a takeoff calc. You know it will work.

Now it it's 1200 feet, worth examining it much more critically. So, it depends.

Mayhemxpc
08-26-2016, 07:15 PM
Maybe I am misreading your post, but I think that you might miss the point. Of course it should be an easy guess that 3500 feet should be enough for a C172 at MGW with reasonable density altitude. That wasn't the point. The issue is being able to stop the airplane safely before you run out of runway if something isn't right. I agree that a pilot familiar with his or her aircraft should know the point at which an abort decision would have to be made without having to figure it out each time. I know without calculating that half loaded, my plane should be at Vr NLT 1000 feet down the runway. Not that I have some inherent insight, it is that I have done the calculation enough that I know the rough parameters by heart. I am constantly surprised at how many pilots don't know the abort point. What is the abort point on your 172? If someone is really familiar with the plane, they don't have to think about in feet, but in time. If not at Vr about 20 seconds after feeding the front engine in, something is wrong. Stop and figure it out.

So I ask pilots to figure that out for me on any review or instruction I give. If the pilot can give me a ball park answer that is fine. After all, we are not going to fly in test pilot conditions.

Lrrryo
08-27-2016, 12:35 PM
Maybe I am misreading your post, but I think that you might miss the point. Of course it should be an easy guess that 3500 feet should be enough for a C172 at MGW with reasonable density altitude. That wasn't the point. The issue is being able to stop the airplane safely before you run out of runway if something isn't right. I agree that a pilot familiar with his or her aircraft should know the point at which an abort decision would have to be made without having to figure it out each time. I know without calculating that half loaded, my plane should be at Vr NLT 1000 feet down the runway. Not that I have some inherent insight, it is that I have done the calculation enough that I know the rough parameters by heart. I am constantly surprised at how many pilots don't know the abort point. What is the abort point on your 172? If someone is really familiar with the plane, they don't have to think about in feet, but in time. If not at Vr about 20 seconds after feeding the front engine in, something is wrong. Stop and figure it out.

So I ask pilots to figure that out for me on any review or instruction I give. If the pilot can give me a ball park answer that is fine. After all, we are not going to fly in test pilot conditions.


Chris,

Good points. One does need to have an abort point/plan in mind before taking the runway and questioning that for a review tells you if he's got that plan done.

Also, we have to accept that we "may or may not" have enough runway to stop short of the end, or continue to fly. A good deal of the time, in twins, we have an area where you just can't do either.... and if you abort, you're going off the end. That's a risk benefit we need to examine on every flight. Fortunately, in most of todays GA twins we can have a "balanced field" with about 5000 feet. I know a lot of POHs say you can do it in less, but I'd be doubtful for most of us.

Lrrryo
08-27-2016, 12:37 PM
Lets parse the question. "Run up" is kind of vague. Lets ask "Do you run the full checklist or the alternate checklist?" Example: the kid brother of a friend made an intermediate stop 30 miles short of destination in a Barron to drop off one passenger. He was in a big hurry and no checklist. He made a fast turn onto the active while pushing the throttles open. Intersection T.O. Rotated early due to less than full runway. It was then that he realized he was still on AUX tanks (they were pretty low). Number one quit while rotating. And everyone here knows why. Whats amazing is everyone lived. Barron destroyed.

Bob,

I hate to hear this. Thanks God everyone lived (except for the Baron). the kid brother made TWO crucial mistakes. He failed to properly do the landing checklist on the previous flight.... and failed to do the before takeoff checklist on the crash flight. For a professional pilot, it's inexcusable.

Lrrryo
08-27-2016, 12:41 PM
Thanks, I only had two single engine landings in those years and no single engine takeoffs. Both shutdowns were control cable failures (one each throttle and mixture) not engine problems. I loved both airplanes but I don't miss making a living in recips!

Jim

Jim,

Perhaps I'm missing something, but why would you shut down with a control cable failure? I've had a few of them, but never had to shut down.

Mayhemxpc
08-27-2016, 09:41 PM
It occurred to me that I never answered the original question.

If if I shut down the engine for however long I do a run up. Lots of funny things can happen during start up. It only takes a few seconds and it makes me feel better. That is not to say I have never stopped an engine, restarted an took off without a new run up. There are certain circumstances where I will skip it.

If I don't shut down the engine -- like land, taxi back and take off again? No, I don't do a new run up. I am sure that someone will be able to explain to me why I should. If so, I will listen attentively.

Jim Hann
08-28-2016, 09:04 PM
Jim,

Perhaps I'm missing something, but why would you shut down with a control cable failure? I've had a few of them, but never had to shut down.
I had two failures, both on a Beech Baron 58 (light twin).

The first one was a mixture control, apparently it goes to idle cut-off when the cable breaks on the Baron. All I know is the fuel flow gradually decreased until the engine was just windmilling. No power left from it, we feathered it so that we would keep on flying. We (I had another pilot with) were mid-weight but the Baron is a good single engine airplane and we were able to continue on to our destination.

The second was a throttle cable. This time I was very light (me, full tanks minus the 1:20 flight, and 5lbs of paper). I found out the cable was broken when it came time to descend. Once I realized what happened I had to reduce power somehow... Since I knew I could maintain altitude and shoot an ILS (it was IFR of course) on one engine at my weight I just pulled the mixture on the uncontrollable engine.

The other thing, it was the right engine both times, not the left.

martymayes
08-28-2016, 09:37 PM
The first one was a mixture control, apparently it goes to idle cut-off when the cable breaks on the Baron. All I know is the fuel flow gradually decreased until the engine was just windmilling.

I had a mixture cable break on a Baron. It remained at the last set position, cruise at 10k feet. When I descended, the mixture was too lean and I had to keep reducing power because the engine was threatening to quit. So I got this idea to put the boost pump on high. It kept the engine running all the way to touchdown.

Jim Hann
08-28-2016, 10:07 PM
I had a mixture cable break on a Baron. It remained at the last set position, cruise at 10k feet. When I descended, the mixture was too lean and I had to keep reducing power because the engine was threatening to quit. So I got this idea to put the boost pump on high. It kept the engine running all the way to touchdown.

We were 75% power, leaned, at 4,500' MSL VFR. The indicated fuel flow gradually went to the bottom of the scale, I can't remember exactly what that was, its been 21 years. The airplane started to yaw as the power fell off. We hit low then high fuel pump and got one or two surges and she was done. It was a BE58, N95BB, s/n TH-333 back in 1995, looks like it is still flying with a different company.

All I know is what happened that time, never had another failure like that. Heck, maybe it was a fuel servo failure, maintenance and the FAA never said boo about it but I'm guessing that the company didn't report anything other than what it had to (or the FAA found out about through other channels). I do know we didn't run out of fuel! (Yep, we checked after we landed!)

Being a recip I don't think they had to report the inflight stoppage under NTSB 830, even though it was a 135 operation.

Lrrryo
08-29-2016, 07:43 AM
I had two failures, both on a Beech Baron 58 (light twin).

The first one was a mixture control, apparently it goes to idle cut-off when the cable breaks on the Baron. All I know is the fuel flow gradually decreased until the engine was just windmilling. No power left from it, we feathered it so that we would keep on flying. We (I had another pilot with) were mid-weight but the Baron is a good single engine airplane and we were able to continue on to our destination.

The second was a throttle cable. This time I was very light (me, full tanks minus the 1:20 flight, and 5lbs of paper). I found out the cable was broken when it came time to descend. Once I realized what happened I had to reduce power somehow... Since I knew I could maintain altitude and shoot an ILS (it was IFR of course) on one engine at my weight I just pulled the mixture on the uncontrollable engine.

The other thing, it was the right engine both times, not the left.

Jim,

Interesting... the mixture should not go to idle with a cable failure, perhaps something else was in the equation. When I had a throttle cable failure (B58) I use used the mixture to control the power going LOP... worked well.

Whatever works to keep the flight safe.

BTW, replacing those cables is a bitch of a job.

Jim Hann
08-29-2016, 05:30 PM
Jim,

Interesting... the mixture should not go to idle with a cable failure, perhaps something else was in the equation. When I had a throttle cable failure (B58) I use used the mixture to control the power going LOP... worked well.

Whatever works to keep the flight safe.

BTW, replacing those cables is a bitch of a job.
I agree, I am not sure what happened with the mixture. Not something we discussed. I know about the replacement work, the throttle cable airplane sat for quite a while because the one mechanic in the shop at the airport where I landed fell off a ladder during it and his back was so messed up he couldn't do anything for quite a while. Incidentally he was replacing the fin boot on that airplane when he fell while waiting for the cable, the boot was working fine but for some reason the company wanted it replaced while the airplane was down. Whoops.