Run-Ups: Where do you do them?

[magicalflights]

Hi,

I have heard two different opinions on where you should do run ups for SEA at uncontrolled airports, assuming there are no run-up areas.

1) Do it on the runway threshold just before takeoff
Problem with this is that you hog the runway for about 5-7 minutes longer.

2) Do it on the taxiway just before entering the runway
Problem with this is that you are powering up to 1700-2000 RPM and there might be another aircraft lining up behind you.

Please advise. Thanks. I train out of a controlled airport, so I don't have as much experience with uncontrolled airports.

[growahead]

Magic, your instructor should advise you. I'm only a ppl, so I'm offering you my opinion, I'm sure others will have different ideas.
In option one, runups should be able to be completed in less than a minute. Don't know where you got the 5-7 minutes. However, in my opinion, it is important that you minimise your time on the runway. If you are delayed on the runway, I suggest that you hold crosswind. This makes you more visible for acft on final, and allows you to monitor the final approach for traffic.
Airfields octa generally require backtracking, it is unusual to have a taxiway to the threshold. In the case that you may be on a taxiway adjacent to the runway threshold, I was taught that your acft should be positioned into wind for the runups (better airflow into the engine, better cooling); this means, usually you will be roughly parallel with the runway, and hence, perpendicular to the taxiway. That means your thrust stream will be directed away from any acft directly behind you on the taxiway.
So, in general, runups before entering and backtracking. If you are delayed briefly on the runway, consider holding crosswind (or at least obliquely, for reasons mentioned). Prolonged delay on the runway should be avoided.
Regards, and happy landings

[fujii]

5-7 minutes for a run up in a single seems a bit long. That said if you are worried about other aircraft how about just using your radio and tell the other aircraft you'll be doing a run up at the holding point of wherever. It comes down to common sense and airmanship.

As you fly around the country you'll probably find out that the airports are very quiet compared to the controlled ones you're used to and you'll be the only one moving.

Where you may encounter traffic is if you attend an air show or fly in. Everyone wants to leave at the same time.

[Cloudee]

Hi,

I have heard two different opinions on where you should do run ups for SEA at uncontrolled airports, assuming there are no run-up areas.

1) Do it on the runway threshold just before takeoff
Problem with this is that you hog the runway for about 5-7 minutes longer.

2) Do it on the taxiway just before entering the runway
Problem with this is that you are powering up to 1700-2000 RPM and there might be another aircraft lining up behind you.

Please advise. Thanks. I train out of a controlled airport, so I don't have as much experience with uncontrolled airports.
I would avoid the runway if at all possible.
Try to do it on a surface that doesn't damage the prop.
Don't direct your prop wash where is isn't welcome.
Do it where your engine noise doesn't disrupt others.
Try and do it into wind.

[Di_Vosh]

G'day,

I'll make an assumption that you're flying a 172, Warrior or similar. I'll put in a disclaimer that it's been many years since I've flown a single engine aircraft.

I can understand that while you're training, things like run-ups take a bit longer than once you're more experienced, but 5-7 minutes seems excessive. Run-ups are normally only required on the first flight of the day, NOT prior to every take-off, despite what some flying schools say.

I can't think of any valid reasons to do run-ups while on the threshold of a runway. Whoever gave you that opinion is wrong, IMHO!

In your other scenario, perhaps you've got a point, but any aircraft taxiing up behind you (presumably you've made some kind of broadcast that you're stopping on the taxiway to do run-ups) shouldn't come so close as to be affected by your prop-wash.

My Opinion:

Find somewhere on the apron that is appropriate and out of the way. That is, somewhere your prop-wash isn't going into a hangar, passenger movement area, parked aircraft, etc. Taxi there. Use your Situational awareness (e.g. looking over your shoulder) to check no-one's come up behind you, and do your run-ups.

Another opinion (once you're more experienced) do your run-ups while taxiing. Not an issue in a 172, Warrior or similar.

DIVOSH!

[magicalflights]

correction, my run up is approximately 1-2 minutes, not 5-7. 5-7 minutes is way too long for run-up, unless I have a triple cheeseburger in hand that I've got to finish.

5-7 minutes is total time from engine start, to taxi a looooong way to runup bay, and finish the run up.

I think I've gotten the answer I need.

1) Do it in a clear area in the apron (with situational awareness)

2) Right before takeoff (it's ok to hold for 1 minute on the runway to do the runup)

As for running up while taxiing, I'd prefer not to do it now, as I have quite a few items on my checklist at the moment, and I prefer not to miss out any crucial items.

I got it right?

So far, I'm in my hour building phase towards CPL, and therefore I'm doing quite a bit of flying into airfields octa, staying a night here and there, and flying out the next day. Hence, it's one of my first few trips where the first flight is octa, hence the need for runups.

[Styx75]

Mayne not recommended until you're cpl, but try run ups while taxiing. Just make sure no ones behind you (and theres not an instructor next to you). Can also be done while back tracking...

[Left 270]

The reason that doing it on the runway can be frowned upon is if you do have a issue, fouled mag or other, is that you are now going to either take longer on the runway until is rectified or possibly have to return to the apron.

Can't say I've never done it, but if there is traffic around I won't, there are usually more convenient places on the apron or before entering. Each aerodrome is different obviously and each would have areas more appropriate then others.

Also if it was a passenger carrying sector the run up would be completed before they arrived anyway.

As mentioned some (most?) aerodromes around the country are very, very quiet.

[Ixixly]

Another factor I'd contribute is that you don't want to get too far away before doing your runups, finding an issue and now having to vacate a runway. A lot of places OCTA you'll find the spot you're parked in will just as likely be perfectly suitable for doing runups. Not to mention the possibility of exacerbating an issue you've just found by having to taxi back to parking.

Most places OCTA you won't find heaps of aircraft parked up, they'll be a single line away from buildings a lot of the time, so just do it on the spot. Why waste time giving all your calls, taxiing out, doing your checklists, getting to the runway, running up there and then finding a fouled plug that needs a few minutes to clear when it could have all been done before taxiing.

Honestly as others have pointed out, it comes down to common sense, do it when necessary, do it away from others as much as practically possible and reasonably necessary, watch your prop wash and IMHO as soon as practical.

[wishiwasupthere]

At country airports, you might find there isn't an obvious spot to do runups, so sometimes it's just easiest to do it where you're parked. If you do though,

1) Check what's behind you. If there is another aircraft, move to somewhere where your prop wash isn't going to kick stones up onto someones plane.

2) If there is a decent amount of wind, at least make some effort to point the nose into wind.

3) If you're going to do your runups where you're parked, during your walk around, have a quick look on the ground beneath the prop. If there are loose stones, kick them out of the way (or brush them out of the way of you're lucky enough to have a dustpan in the plane)

[mcgrath50]

Every situation is different and you want to consider a few things when picking where to do it including:
Surface (ideally you want a somewhere sealed)
Surroundings (try not to blow crap into a hangar)
Traffic (try not to hold people up on taxi ways or even worse runways)
Warmth (you want your engine to be a little warm, so if you choose to do it at parking position you are sitting there for a long time. You could use the taxi to warm the engine but then you could be blocking someone)

There is no right answer to this, just better ones (there is probably wrong ones though).

Remember run ups and run up or pre take off checks are two different things. You can sit in your parking spot and do all of the checklist except the physical run up. Taxi to the holding point, do an idle check before stopping. Power up, mag check, carby if applicable, pull power back to 1,000 (shouldn't take much longer to do than say). Conduct line up checks. Go. If you detach the run up from the rest of the pre take off checks you make choosing a spot to do it much easier.

[drpixie]

Surface (ideally you want a somewhere sealed)
Surroundings (try not to blow crap into a hangar)
Traffic (try not to hold people up on taxi ways or even worse runways)
Warmth (you want your engine to be a little warm, so if you choose to do it at parking position you are sitting there for a long time. You could use the taxi to warm the engine but then you could be blocking someone)


I can hear a checklist coming up ... just don't tell my (just now ex) CFI - presentations, standards, and checklists for anything/everything :ugh: I'll admit they have their place, but that place is not everywhere.

There's way too much formulaic, prescriptive stuff in aviation. Just understand what is important (AND WHY) and use common sense, please.

[Old Akro]

Why are you doing runups?

Runups are done for different reasons in different aircraft at different times of the day.

Frankly, runups are not very important for a fixed pitch C172. You can tell if the mags are working pretty much at idle and at 1600 static rpm (or whatever) the engine is not making much power, so its not testing the mags under load. Largely its a practice carried over from Tiger Moths. (come in Jaba)

On a cold day, runups in a turbocharged twin are a prolonged affair. I'm warming the oil, checking fuel pressure, vacuum, prop governors, feathering accumulators, alternators.

On difficult runways, in fixed pitch aircraft, I've done mag checks during the take-off run.

Do runups for a purpose you have thought about - not as a robot by rote.

[Centaurus]

Another opinion (once you're more experienced) do your run-ups while taxiing. Not an issue in a 172, Warrior or similar.

Unbelievable that some pilots actually do that. Maybe "once you're more experienced" is just another way of saying the pilot is over-confident and exhibits very bad airmanship. It certainly is an "issue" in any aircraft including light singles such as a 172, Warrior or similar. It means dragging the brakes, head inside the cockpit while taxiing instead of outside the cockpit and leads to fast taxiing even while having the brakes on. :ugh:

[gerry111]

Di_Vosh wrote:

"Run-ups are normally only required on the first flight of the day, NOT prior to every take-off, despite what some flying schools say."

I'm happy to pay for the small extra cost of doing an engine run-up, prior to every take off.

[Di_Vosh]

Unbelievable that some pilots actually do that.

Just the way I was trained, saw others trained, and experienced throughout my time in GA. I only worked for four GA operators. All did run-ups on the run, and all expected their charter pilots to do so.

IME, most (not some) pilots in GA "do that".

Maybe "once you're more experienced" is just another way of saying the pilot is over-confident and exhibits very bad airmanship.

And Maybe "once you're more experienced" means just that: A pilot has enough experience and can safely 1: run the rpm up to 1500; 2: check the carby heat (if fitted); and 3: drop each mag, before going back to idle.

If the aircraft is being operated daily and correctly it should take all of around 15 seconds to perform. If you've got to clear a mag or something more serious, then sure, stop and sort it out.

It certainly is an "issue" in any aircraft including light singles such as a 172, Warrior or similar. It means dragging the brakes, head inside the cockpit while taxiing instead of outside the cockpit and leads to fast taxiing even while having the brakes on.

Disagree. It may do all those things, but doesn't have to, and shouldn't if the pilot uses their brain.

"head inside the cockpit while taxiing": There are other pre take-off checks that pilots do, and all of them require the head inside the cockpit for some of the time. Are you advocating that all these be done while stationary?

The OP is training for a CPL. If a CPL can't use their judgement as to whether it's safe to do simple checks while taxiing, then god help them if they're airborne and have to use their judgement in an abnormal or an emergency.


DIVOSH!

[uncle8]

If you do run up while lined up on the runway, there is no need to reduce to idle after your checks. You already know that it idles OK so power up, check what you have to then go. I've just timed it - 30 seconds for a CS 0-360.

[Judd]

The OP is training for a CPL. If a CPL can't use their judgement as to whether it's safe to do simple checks while taxiing


Simple checks? These are run-up's where temps and pressures should be closely scrutinised and maximum rev drop between magnetos observed, suction checked at idling. If a constant speed prop, exercising of the prop is done. All the while using differential brake dragging if in a twin checking one engine at a time. What is there to gain from all this? If it is good enough (i.e. safe) for CPL holders to conduct engine run ups while taxing including twins, then it is logical to train CPL candidates to do the same while under training. Practice makes perfect. Have yet to see a flying school that teaches run ups while taxiing and certainly never on a CPL flight test with an Examiner on board.

To deliberately conduct engine run-ups while taxiing is sheer folly better known as cowboy antics, cutting corners, using the excuse to save the boss a few cents (never mind brake wear and possibility of hot brakes caused by brake dragging and costing the boss more money)

[Awol57]

The original question was about a Single Engine.

Moving or not I seem to recall the actual run up part of the check in a C172 took about 15 secs in total (assuming the engine was already warmed up and no issues found). Maybe less. It's been a number of years since I flew but on a long taxiway with no one around 15 seconds at 1700RPM from idle might require a tap or 2 on the brakes. I can't remember ever having to ride the brakes to keep the aircraft under control. If there were other aircraft around then it just wasn't done.

[Styx75]

Its not even about riding the brakes. At taxi speed, the brakes are barely being working compared to when they are used during the landing roll from 60kts or more. Its just a non issue.

Being familiar enough with the cockpit to do the process safetly and being aware of your propwash are the considerations.

[Sunfish]

seaplanes do run ups while taxiing every time. I've done a run up while backtracking at Maree because the place was busy and congested, however I was the last person to use the aircraft and it was ok the night before and I had been using the aircraft continuously for a week so I thought I knew it's behavior reasonably well enough to spot any obvious deviation from normal.


the 210's all did their run ups about half an hour before loading pax.

[Di_Vosh]

Who knew that a C172 or PA28 could be so complicated?

Simple checks? These are run-up's where temps and pressures should be closely scrutinised and maximum rev drop between magnetos observed, suction checked at idling.

Better read your C172 POH again mate! Nowhere does it say T's & P's should be checked (let alone "closely scrutinised") during a run-up. I would suggest to you that "suction checked at idling" be done when the engine is actually idling and not during a run-up.

I'm not that special, but I could do all that by glancing inside at the appropriate time while keeping an eye out where I was going.

All the while using differential brake dragging if in a twin checking one engine at a time.

Please don't put words in my mouth. Show me where I suggested doing this in a twin or a constant speed prop.

Have yet to see a flying school that teaches run ups while taxiing

So what? Like I said earlier, I was relating my experience. Yours is (obviously) different.

To deliberately conduct engine run-ups while taxiing is sheer folly better known as cowboy antics, cutting corners, using the excuse to save the boss a few cents (never mind brake wear and possibility of hot brakes caused by brake dragging and costing the boss more money)

ROFL! The horror! Where's Helen Lovejoy when you need her?

As for brake wear and "hot brakes", sure if you spend 1-2 minutes doing a run-up but who does that? Like I (and plenty of others) have said, run-ups in something like a 172 should only take around 15 or so seconds. If the aircraft is flown every day, and operated correctly (i.e. as a typical charter aircraft would be) this is all it should take.

As I said earlier, a CPL is going to be required to use their judgement. If they judge that the circumstances and their competence can allow them to do run-ups while taxiing, I can't see a problem.

I'm happy to pay for the small extra cost of doing an engine run-up, prior to every take off.

Not everyone shares that opinion, particularly as it's not a requirement.

DIVOSH!

[certifs]

I'm happy to pay for the small extra cost of doing an engine run-up, prior to every take off.

Glider towing?

[Jabawocky]

Akro…..I have been holding back. There is a lot of good stuff posted already, some OWT's and stuff learned by rote. The problem is not enough folk appreciate science and learn the facts abut what works, why, and when.

I too was once a victim of the "just do what my instructor taught me" method of learning to fly. There will be many here who know what i mean. They too will have become advanced in their learning. Many are Advanced Pilots now by learning from various sources. (I went back and capitalised that….kind of tells you where the name came from :-) )

I will post some thoughts a little later when I can dedicate some time.…..end of year, another US trip to plan, farm stuff list as long your arm, shooting comp…..why am I even looking on pprune :-/

DiVosh, 15 seconds :ok: you nailed it!

Back later :ok:

[wishiwasupthere]

One of the things I was taught in my first job where I regularly flew in and out of unsealed strips where there may not have been somewhere 'suitable' to do static run ups was that it's cheaper to replace brake pads then a prop that has been filed back to an inch of its life.

[Squawk7700]

I'm seeing more and more airfields (particularly Council owned ones) installing small concrete pads which is good, particularly if they have a gravel strip.

[ForkTailedDrKiller]

To deliberately conduct engine run-ups while taxiing is sheer folly better known as cowboy antics,Geez you read some drivel on here! Yep that's me, an old cowboy.

I was going to write a more detailed reply and then I thought, "Nah, I can't be bothered"! :ok:

Dr :8

[Squawk7700]

http://www.saturdayeveningpost.com/wp-content/uploads/satevepost/9470517_72dpi_nocallout.jpg

http://download.aopa.org/images/eFT2014/141205cowboy.jpg

[Jabawocky]

A few of the regulars here know me well. And I am a bit under the pump, but I planned to write a good response, so here it is, with a little help from a friend :ok:.

Mag Checks. Most done the way the instructor teaches are almost pointless in terms of testing the ignition components. It does prove that one of the mags have not been stolen :}. The best time to do a mag check is in flight, at high power and Lean of Peak. This is by far the most diagnostic and with an engine monitor the best way to define a problem. Period!

In order of diagnostic value it goes like this;
High Power in flight LOP looking for all EGT's to rise
High Power in flight ROP looking for all EGT's to rise
1700+/- a bit on ground LOP looking for all EGT's to rise
1700+/- a bit on ground ROP looking for all EGT's to rise
The way you were taught full rich and looking at RPM drop.

These can be done easily on the run or static when on the ground, as you gain experience. Newbies might be best to do it in a run up bay or holding point.

If you own the plane, the only one who flies it, and did a mag check on the way in last flight, then a 1000 RPM flick/EGT's all rise, flick same again….good to go. Of course an EMS is required ;). High power prop damage is an issue so the less you do this the better.

After any maintenance do a serious 1700 or so RPM LOP mag check and study it on the EMS for about 10 seconds on each mag. I trust nobody or nothing if anyone has been under the cowl other than to check the oil.

As I am not keen on typing pages, the original poster could well learn a lot from reading this article written by my colleague and good friend John Deakin, who I am pleased to report is doing really well for an old fella when Leisa and I spent the day with him two weeks ago in sunny Camarillo. :ok:

Pelican's Perch #77: Startups & Runups - AVweb Features Article (http://www.avweb.com/news/pelican/Pelicans-Perch-77-Startups-and-Runups-186619-1.html)

magical flights I hope this helps you :ok:

[Tee Emm]

Jaba W. As much as I admire John Deakin's "Pelican's Perch" engine handling series, I must say I am surprised when he said that run up procedures should be conducted with the park brake off and holding on the brakes by pedal pressure alone.

His article states:
Set the Brakes?

A very strong "No!" answers this question, for those airplanes with anything but power brakes.
............................................................ ............................................................ ....................................

If Deakin's technical argument for not using the park brake when stopped is valid, then it would suggest the aircraft certification process is flawed.

While I have often see pilots conduct run up's using brake pedal pressure only, it is an unwise policy in general; especially at night or in heavy rain where it is sometimes difficult to pick movement of the aircraft inching forward or on a rear sloping surface moving backward.

The most common reason for some pilots not using the park brake in general aviation aircraft is that from the beginning of their ab-initio training they are taught by their instructors not to trust the parking brake. This is negative teaching. It stems possibly from another fact in general aviation and that is many pilots are reluctant to write up defects in the maintenance release for fear of management or aircraft owner adverse reaction.

A pragmatic reader can understand why some pilots are wary of using the park brake for run up's. Good airmanship would dictate that until you are sure the park brake is holding correctly at high power, it is wise to be ready to apply prompt brake pedal pressure if the aircraft begins to move. But don't forget to promptly close the throttles.

If the park brake is inoperative or not holding, then legally you are bound to write it up in the maintenance release. If the defect is not cleared before the next flight, at least the next pilot is aware when he studies the maintenance release before flight. Too many pilots are happy to let the next pilot wear an unreported defect with the callous attitude of `not my problem mate`and let the next bloke carry the can.

In the POH for the venerable Cessna 172 the manufacturer's checklist states that before starting the engines "Brakes ---TEST and SET". The Securing Airplane checklist states "Parking Brake---SET".

During a run up, holding on the brake pedals rather than setting the parking brake, it only takes a momentary lapse of concentration to inadvertently relax one or both feet from the pedal pressure; particularly if heads down events are taking place in the cockpit such as writing down clearances or briefings. The parking brake is good insurance. In event of an incident involving the non-use of the park brake when it should have been on, the lawyers would have a field day citing the manufacturer's POH.

[Me_3]

Jaba W. As much as I admire John Deakin's "Pelican's Perch" engine handling series, I must say I am surprised when he said that run up procedures should be conducted with the park brake off and holding on the brakes by pedal pressure alone.

I'm not sure what aircraft you have flown, but when doing runups the park brake is dangerous...

First point, Taildraggers, at no point would I want to do power runs with the park brake locked. If the tail starts to lift for whatever reason, or one brake slips the last thing you would want is a locked up park brake.

2nd. any high power A/C. A simple 172 isn't really an issue, but doing a full power run on a lot of high powered aircraft the brakes can barely hold, or the tyres skid. Much safer to have feet on the brakes, and if it does move have some controllability. (yes, you also pull the power but having directional control helps)
If your wondering what singles won't hold? Here is a few i've done runups in during the last few months.
- DHC2 Beaver (taildragger also applies)
- C182 with O550 - just drag the wheels if the brakes hold
c206/c207 - just drag the wheels if the brakes hold
Glastar with 180hp - drags the wheels
C172XP - Drags the wheels if not careful

and i've seen plenty of twin drivers drag the wheels when they get the bright idea to run up both at once....

The park brake is a PARK BRAKE. To be used when PARKING, or sitting idle.

[Jabawocky]

TM

I will disagree purely on the basis of even a perfectly functioning park brake might not be SET with enough brake pressure or uneven pressure, and during the run up you then jump on the pedals to find that no matter how hard you squeeze it makes not difference. Yes I know you can reduce power and it should stop moving…..but that is easy for some to overlook.

Personally I am far happier holding with my feet, after all they are used to applying brakes, and brake feel is something you acquire quickly. My other reason for this is you shall not be head down, even at night it should be less head down. An instrument scan is all you do, you may select one mag and let it sit there for 10 seconds "watching" the EGTs all rising, but in reality you glance at the EMS, not stare at it.

So while I understand your concern, if done properly it is really not a concern at all.

Lastly, just because it is written in the POH, does not make it the best or smartest way to do things, especially when they were written long before the EMS was developed. :ok: But if you feel compelled to use it, go right ahead! But teaching advanced or better methods is something we should be aspiring to. And if a particular aircraft for some really good reason should not be done that way then fine, don't do it. Know your aeroplane! Most GA's I would say it is better not to.

Does that make sense?

[Lead Balloon]

I do mine during the take off roll and top of descent, unless I'm compelled to leave a sacrifice to the OWT Gods.

I might select the L and R mag during taxi to check whether a mag or plug is completely dead (or has been stolen - where do you live, Jabba?) if something doesn't feel right. But that's about it. Any problem found during a run up at e.g. 1700 or 1800 RPM can usually be found at idle RPM. Some problems at full power won't be found during a run up at e.g. 1700 or 1800 RPM.

You have to check all the numbers when you go balls to the wall anyway ...

And if the one-in-a-million happens and the prop governor won't move the blades off the fine pitch stops when you get to TOPC, take a deep breath and ...

Relax.

PS: I got me one o' them new fangled en-jine monitors. Yee har!