Full and free controls check
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Full and free controls check
Assume your aircraft has a steered nosewheel (with the rudder pedals) with a totally direct linkage (no springs etc) from the pedals to both the rudder and the nosewheel.
IMHO, the only way to test the rudder movement range is during taxi, when the nosewheel is free to turn, and by gradually applying the pedals. Obviously you need to make sure there is enough room because the aircraft will turn left and right as you do it
It can be done without much or any forward motion but a huge pedal force is required, obviously - like turning the steering wheel in a car when not moving.
Would anybody here test for full rudder movement with a rapid and full-travel left and right pedal depression, while moving forward slowly?
IMHO, the only way to test the rudder movement range is during taxi, when the nosewheel is free to turn, and by gradually applying the pedals. Obviously you need to make sure there is enough room because the aircraft will turn left and right as you do it
It can be done without much or any forward motion but a huge pedal force is required, obviously - like turning the steering wheel in a car when not moving.
Would anybody here test for full rudder movement with a rapid and full-travel left and right pedal depression, while moving forward slowly?
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Peter, Its almost like the proverbial how long is a piece of string question.
It depends totally on the aircraft type, what does it say in the POH for rudder checks? Thats always going to be be the standard point of reference.
If you look at some tail draggers, you can lift a the tail off the ground while doing your walk around and check the rudder is free from limit to limit. Others have castoring nose wheels, some have spring linked rudder pedals to nose wheel. It really does depend on the type of aircraft and what it says in the POH.
It depends totally on the aircraft type, what does it say in the POH for rudder checks? Thats always going to be be the standard point of reference.
If you look at some tail draggers, you can lift a the tail off the ground while doing your walk around and check the rudder is free from limit to limit. Others have castoring nose wheels, some have spring linked rudder pedals to nose wheel. It really does depend on the type of aircraft and what it says in the POH.
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No. My little legs aren't strong enough.
Seriously though I do it with the rest of the taxi checks. From parked release the brake, move forward very slowly for the toe brake check. Continue to taxi at normal speed and check the rudder/nosewheel steering as part of the instrument checks: left pedal, compass, TC, AI, etc.
Whether that's the correct way or not I couldn't set claim, but I feel that rapid full travel at a slow speed wouldn't give me the familiar tactile sense that I'd expect for normal operation. Also I speculate, that the rapid movement at slow speed could potentially induce a force that would damage further any hidden defect, not necessarily being properly noticed until landing. And I like a nose leg and (decent) steering after touchdown!
Seriously though I do it with the rest of the taxi checks. From parked release the brake, move forward very slowly for the toe brake check. Continue to taxi at normal speed and check the rudder/nosewheel steering as part of the instrument checks: left pedal, compass, TC, AI, etc.
Whether that's the correct way or not I couldn't set claim, but I feel that rapid full travel at a slow speed wouldn't give me the familiar tactile sense that I'd expect for normal operation. Also I speculate, that the rapid movement at slow speed could potentially induce a force that would damage further any hidden defect, not necessarily being properly noticed until landing. And I like a nose leg and (decent) steering after touchdown!
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I guess it depends on what you call "rapid".
While training in the PA28 I don't recall doing a specific check on rudder travel other than just noticing any restrictions during normal taxi. In the normal course of taxiing you typically make at least one left and one right turn to get to the runway (including maneuvering for the runup) so you have a pretty decent idea on whether things work. But I admit you don't necessarily apply full rudder in both directions this way.
When I started doing aeros in the R2160 we were taught to do a full and free rudder check specifically. At my club we typically use the former heli platform next door. This is done at slow taxi speed - it's a tight area. Full right rudder application with moderate force requires about 1-1.5 seconds to reach full deflection, then full left rudder requires about 1.5-2 seconds to reach full deflection. In that time the aircraft has traveled forward maybe some 20 meters, and has a sideways deflection of the taxi path of about 5-7 meters. And is incidentally nicely lined up with the exit of the heli platform.
So the full check will take about five seconds in total, during which the aircraft moved forward some 20 meters. That seems to be the maximum that this particular aircraft will handle comfortably, without feeling overstressed, squeeling of tires etc.
I would not check rudder movement while standing still with any sort of linked nosewheel. If only because of the wear on the tires. Unless it's spring-loaded and the POH specifically permits it.
(On the other hand, in a castoring nosewheel aircraft like the DA40 you are continuously applying full rudder deflection just to keep the aircraft straight during taxi. No need for specific checks there.)
While training in the PA28 I don't recall doing a specific check on rudder travel other than just noticing any restrictions during normal taxi. In the normal course of taxiing you typically make at least one left and one right turn to get to the runway (including maneuvering for the runup) so you have a pretty decent idea on whether things work. But I admit you don't necessarily apply full rudder in both directions this way.
When I started doing aeros in the R2160 we were taught to do a full and free rudder check specifically. At my club we typically use the former heli platform next door. This is done at slow taxi speed - it's a tight area. Full right rudder application with moderate force requires about 1-1.5 seconds to reach full deflection, then full left rudder requires about 1.5-2 seconds to reach full deflection. In that time the aircraft has traveled forward maybe some 20 meters, and has a sideways deflection of the taxi path of about 5-7 meters. And is incidentally nicely lined up with the exit of the heli platform.
So the full check will take about five seconds in total, during which the aircraft moved forward some 20 meters. That seems to be the maximum that this particular aircraft will handle comfortably, without feeling overstressed, squeeling of tires etc.
I would not check rudder movement while standing still with any sort of linked nosewheel. If only because of the wear on the tires. Unless it's spring-loaded and the POH specifically permits it.
(On the other hand, in a castoring nosewheel aircraft like the DA40 you are continuously applying full rudder deflection just to keep the aircraft straight during taxi. No need for specific checks there.)
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Aircraft type appropriately, I like the check during a walk around that the rudder seems to be connected, and is not obstructed locally from free motion. It's also nice to assess if possible that if it reaches full motion, it will not hang up there, but this assessment is not always possible. This was a concern in a silly AD against C 150's. Certainly on some type you can damage the rudder trying to move it full travel whie parked.
Once that's established, I like to assure full rudder travel at the pedals during taxi, and if I can see the rudder moving as it should bonus.
I have had five maintenance failings of rudders/steering, all of which were flyable, but were none the less wrong, and noticeably so. None were detectable at the walk around level of inspection. Were any have been on a twin, and I'd lost an engine, it could have been a real problem!
Once that's established, I like to assure full rudder travel at the pedals during taxi, and if I can see the rudder moving as it should bonus.
I have had five maintenance failings of rudders/steering, all of which were flyable, but were none the less wrong, and noticeably so. None were detectable at the walk around level of inspection. Were any have been on a twin, and I'd lost an engine, it could have been a real problem!
Regarding rudder, I also agree that it depends very much on type. Many taildraggers the tailwheel and rudder are linked by springs so operation of the rudder is doable. Some types (Grummans, Shadows...) have a castoring nosewheel so a full check on the rudder is no problem. On the other hand in, say, a C172 or a PA28 yes, rudder/nosewheel on taxi.
I also make a point of moving the control surfaces by hand whilst looking in the cockpit (or with the aileron, at the other aileron) to ensure there's no unwanted freeplay in the system.
And ALWAYS check that everything (but especially the ailerons) goes the right way, particularly if you fly gliders or microlights, which may well have been de-rigged then re-rigged between flights.
Bigger than *most* of us fly, but hydraulics changes the whole game of-course. Ditto FBW.
G
I also make a point of moving the control surfaces by hand whilst looking in the cockpit (or with the aileron, at the other aileron) to ensure there's no unwanted freeplay in the system.
And ALWAYS check that everything (but especially the ailerons) goes the right way, particularly if you fly gliders or microlights, which may well have been de-rigged then re-rigged between flights.
Bigger than *most* of us fly, but hydraulics changes the whole game of-course. Ditto FBW.
G
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I wrote
e.g. a TB20.
What would concern me is the huge pedal force required to do a rapid L and R full-travel-all-the-way-to-the-stops check.
Assume your aircraft has a steered nosewheel..
What would concern me is the huge pedal force required to do a rapid L and R full-travel-all-the-way-to-the-stops check.
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What would concern me is the huge pedal force required to do a rapid L and R full-travel-all-the-way-to-the-stops check.
Whatever the POH says, if it were mine......
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The other ting with control check is don't do it in the same order every time because it can be free going one way and not the other,
The reason why I know this is because for some reason I had a FO do it the opposite way round to normal and I was just about to mention it when the bloody TCAS VSI unit came out the panel with a crunch.
Turn out that if you went forward left back right The gubbins at the back was clear but if you went forwards right back it caught on the back of the unit.
The unit had been installed for over a year when we discovered this. Out of a fleet of 7 aircraft 2 had this feature.
The reason why I know this is because for some reason I had a FO do it the opposite way round to normal and I was just about to mention it when the bloody TCAS VSI unit came out the panel with a crunch.
Turn out that if you went forward left back right The gubbins at the back was clear but if you went forwards right back it caught on the back of the unit.
The unit had been installed for over a year when we discovered this. Out of a fleet of 7 aircraft 2 had this feature.
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The interpretation of the POH procedure hangs on the interpretation of the words on page 71 and 77 of the POH (a generic one is e.g. here).
My view is that no way one should force the pedals fully against their mechanical stops unless there is sufficient forward motion on the tarmac to allow the nosewheel to follow the pedals easily.
IOW, there is no way to do this, without excessive stress on the rudder/nosewheel linkages, unless you are taxiing at the time.
And it will result in significant heading excursions on the taxiway.
My view is that no way one should force the pedals fully against their mechanical stops unless there is sufficient forward motion on the tarmac to allow the nosewheel to follow the pedals easily.
IOW, there is no way to do this, without excessive stress on the rudder/nosewheel linkages, unless you are taxiing at the time.
And it will result in significant heading excursions on the taxiway.
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If it takes more force that would be involved in normal taxiing, then I would say that you're doing it too quickly, and likely to cause damage in the long run.
I would also say that if you are doing it really quickly, you get a wobble rather than a proper turn, and don't really know if the nose wheel has turned properly. All you know is just that the pedal has made full travel and you got a bit of a turn.
I would also say that if you are doing it really quickly, you get a wobble rather than a proper turn, and don't really know if the nose wheel has turned properly. All you know is just that the pedal has made full travel and you got a bit of a turn.
Hmm, unfamiliar. In my 182 I can move the pedals to full deflection while static on the ground, and the rudder moves too - or I can move the rudder by hand (and do on every pre flight). And that's true for every type I'm reasonably familiar with - including taildraggers (Citabria, Pitts, T6, ...). They all have some kind of spring or bungee cord in the linkage. It may take a bit more force but nothing extraordinary or to the point where you worry you might break something. (We won't talk about the Great Lakes which seems to have a very thin elastic band rather than an actual spring).
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In my 182 I can move the pedals to full deflection while static on the ground
It is type specific. On the TB20, you cannot do this at all - short of a ridiculous force on the rudder, sufficient to force the front tyre to rotate statically on the tarmac.
Yet, not doing it is a good way to help fail a 170A if you get the "right" examiner
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Peter;
On a 170A its a question of playing the game, I personally would not go for a "rapid left right full control manouvre"; If you brief the examiner that you will carry out a full and free in seperate parts ie "as we turn left from dispersal I will check full left rudder and full right as we turn into wind for power checks" and highlight the reason why then he should not fail you if you have good airmanship/POH reasons.
I've just checked with FF and VH and when we did both 170 and IR power checks were carried out into wind (different from your other post, god knows why that has changed)
SND
On a 170A its a question of playing the game, I personally would not go for a "rapid left right full control manouvre"; If you brief the examiner that you will carry out a full and free in seperate parts ie "as we turn left from dispersal I will check full left rudder and full right as we turn into wind for power checks" and highlight the reason why then he should not fail you if you have good airmanship/POH reasons.
I've just checked with FF and VH and when we did both 170 and IR power checks were carried out into wind (different from your other post, god knows why that has changed)
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Perhaps get someone to pull the tail down while parked so the nose is off the ground. Then you can test the rudder anyway you please 
Definately the only way to check is while moving, the first three checks as soon as the taxi starts are full left rudder, full right rudder, brakes working. When you're the one paying for the nose leg and new tyres, you certainly want to reduce the long term wear and tear/damage.
Sounds like you're having a real hard time with the 170a.
Definately the only way to check is while moving, the first three checks as soon as the taxi starts are full left rudder, full right rudder, brakes working. When you're the one paying for the nose leg and new tyres, you certainly want to reduce the long term wear and tear/damage.
Sounds like you're having a real hard time with the 170a.
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Perhaps get someone to pull the tail down while parked so the nose is off the ground
You would definitely break off the tailcone.
It's not a C150 (which I know you can do that with). It's so damn heavy you would need a hurricane to move it even if not chocked.
Sounds like you're having a real hard time with the 170a.
Looking for a new FTO.
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Peter try Kevin Rowel in sherburn.
If he can get me towing the line he can do it for anyone.
He will give you exactly what you need to get through with zero nonsense.
Yes I know its a pain and some of the things they want you to do you think are bollocks. But to be honest they have stood me in good stead through out my career and I have used pretty much everything that I was tested on includng the partial panel work
If he can get me towing the line he can do it for anyone.
He will give you exactly what you need to get through with zero nonsense.
Yes I know its a pain and some of the things they want you to do you think are bollocks. But to be honest they have stood me in good stead through out my career and I have used pretty much everything that I was tested on includng the partial panel work
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I've always been taught to do full rudder checks - but I have a nice big apron to do them on before reaching the taxiway. At walking pace, I deviate off the center line to one side (say left) then use full right rudder, then left full rudder to put myself back on the center line, ensuring I'm reaching the stops each time. The total deviation off the center line isn't more than a few meters.
I suppose the main question is have you checked all of the controls that can be checked. If you can check them - you should check them!
I suppose the main question is have you checked all of the controls that can be checked. If you can check them - you should check them!
Not sure if it's relevant or wise, but my approach is exactly the other way round: the bird sitting on the apron, I pull her tail down with one hand, and with the other I check the rudder against its limits. On good days I keep half an eye on the pedals moving accordingly; and if another person is available, they get requested to confirm the nosewheel's compliancy.
