Dumb student pilot question Rudder related

Tony R

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So when you let off the rudder pedals in the air are they supposed to self center or do they stay where you last had them?

I know.... I only have 3.7 loggable hours, each in a different plane... So I will certainly have very basic questions.
 
I thought so too, now there was more than my little brain could absorb when I flew an Alpha trainer on Wednesday, but I thought that it didn't return to neutral. Again I was having a helmet fire so details are Shakey.
 
I thought so too, now there was more than my little brain could absorb when I flew an Alpha trainer on Wednesday, but I thought that it didn't return to neutral. Again I was having a helmet fire so details are Shakey.
On the ground, it may not return to nuetral, depending on the type of aircraft. If it has a catering nose wheel, it may not auto-center. Also, when throttling up and on the take off roll and climb out, you need to apply right rudder to counteract the left turning tendencies, so it may seem like the rudder isn't centering - in this case it is centering, but you need right rudder to keep going straight.
 
There are return springs, but what do you mean, "let off the rudder pedals"? Put them where they need to be and keep them there.
 
The rudder should return to its trimmed position if you are not pressing on any of the pedals. Most planes have rudder springs that will center the rudder if not actively engaged, however the rudder may not return to a neutral position due to air loads and trim tab settings. The trim tab is typically set so that the plane remains level with no slip or skid in cruise configuration. But in general the rudder does nothing to change the attitude of the aircraft unless a rudder pedal is depressed.
 
There are return springs, but what do you mean, "let off the rudder pedals"? Put them where they need to be and keep them there.
I would assume he means taking your feet off of them entirely... But no reason really to be doing that in the air or on the ground (unless giving someone else the controls, with proper transfer)
 
It does have a steerable nose wheel, perhaps that is why when I released pressure it didn't seem to return to neutral.

I will pay more attention on my next flight.
 
I would assume he means taking your feet off of them entirely... But no reason really to be doing that in the air or on the ground (unless giving someone else the controls, with proper transfer)

I logged 10,000 hours before I learned they were more than ground steering and foot rests….

My first Taildragger flight was HILARIOUS! I base that on the hollering and hooting coming from the back seat whilst I was experiencing a helmet fire… I saw both sets of runway edge lights no less than 4 times each on ONE takeoff. Impressive me thought.

They did NOT seem to self center, but that could have been me. Academically, I know they do.

Tools, Navy jet guy… worst offender known to aviation. Don’t even get me started on that other weird thing y’all do… what’s it called? Oh ya, the “flare”, woooooo….
 
What is it that you Naval Aviators say? Flare to land, squat to pee? Or is that a career-damaging quip these days?
 
Closest I came to being killed as an instructor was a 24,000 hour 747 Captain.

He needed to get to a meeting, and it was quicker and easier to just have me ride along rather than getting checked out.

First take off (C-150) he firewalls the throttle somewhat rapidly, and it seems his feet were not on the rudder pedals. This was at dusk, and we did about a 45 degree left turn and headed for the trees. I added a boot full of rudder and kept us on the runway.
 
A couple of SLSA planes that I have flown (same model) would return to near center but not all the way. Most pilots of that model reported that theirs did not exhibit that problem. I suspect that there may have been something out of adjustment.
 
So when you let off the rudder pedals in the air are they supposed to self center or do they stay where you last had them?

I know.... I only have 3.7 loggable hours, each in a different plane... So I will certainly have very basic questions.
They'll go back to 'neutral' but I put this in quotes because there's some nuance to this. They'll generally, free of outside influence, return to align with the natural slip stream, like a flag lines up with the wind. If you are going straight and level they'll generally be "neutral" but go into a power on stall with your feet on the floor and that rudder will deflect naturally into the spiraling slip stream.
 
Another rudder tip regarding rudders with fixed trim tabs (like on the 150/152/172): the size and curvature determines the trim setting. When properly rigged, the airplane will fly hands-off straight & level cruise only at 1 specific airspeed. Flying slower requires a bit of R rudder, faster requires a bit of L rudder, to maintain coordination. The trim tab applies a touch of R rudder, so a more curved trim tab will apply a bit more R rudder and be neutral at a slower cruise airspeed than a less curved one. So you can bend the rudder trim tab to fine-tune to your preferred cruise speed.
 
The springs on the rudder pedals of many (most?) light aircraft are not for the purpose of centering; they're to maintain tension in the rudder cables. That said, they do tend to center the rudder from large deflections, but close to center the spring force is nearly equal on both sides so they won't push the rudder all the way to center.

Aerodynamic forces will tend to center the rudder, provided that the trim tab isn't pushing it off center.

Friction in the system will tend to prevent it from centering by itself.

Many student pilots, who are unused to using both feet against each other, will unconsciously hold pressure on one side or another.

And as others have pointed out above, the aircraft's yaw trim changes in different flight conditions, requiring the pilot to hold pressure one way or the other. Ideally, it's neutral in cruise flight, where you spend most of your time.
 
When I need the rudder, I don't rely on them to self center. Two feet on the pedals, put the rudder where it needs to be. That said, I'm flying an airplane with a yaw damper so sometimes the feet get a little lazy.
 
I was not near full deflection, the ball was barely outside of the line.... I think with all this information I'm starting to put together what is happening. I guess my expectation, wrongfully, was that when I return from a turn to straight and level, the plane will self coordinate.... My takeaway is always fly the plane, never expect it to fly for you. Also kudos to my CFI for letting me fly uncoordinated and not helping me with the pedals. I would look down and say oops uncoordinated and he'd say yup, fix it.

I go up tomorrow and will pay particular attention to the rudder.

Expect a pirep with a few more "fundamental" questions. I owe all you a beer. Thank you.
 
The rudder should return to its trimmed position
That, at least in PA-28’s. In my Warrior, there’s a knob to adjust the tension of the springs so as to trim the rudder. In a sustained climb, I’ll end up twisting it clockwise until my right foot doesn’t need to press anymore. Once leveled out, I turn it counterclockwise until my left foot is relieved.

Once the forces are neutralized, the right pedal will be slightly depressed (and held there by the springs) during a climb and will be even(ish) once trimmed in level flight.

I use the trim pretty much every flight, to some degree.

But the springs return the pedals and rudder to their last trimmed position, not necessarily “neutral”, at least on Pipers.
 
I was not near full deflection, the ball was barely outside of the line.... I think with all this information I'm starting to put together what is happening. I guess my expectation, wrongfully, was that when I return from a turn to straight and level, the plane will self coordinate.... My takeaway is always fly the plane, never expect it to fly for you.
...
You may especially notice this when returning to straight & level flight from a steep turn. You must apply both aileron and rudder opposite the turn while returning to level flight, while keeping the controls balanced to each other & coordinated.

From the airplane's frame of reference, returning to straight & level flight from a L turn is much like entering a R turn. And vice versa.

Another aspect to consider with coordination is static vs. dynamic. By static I mean you are established in a constant rate turn - the bank angle, airspeed, pitch, are not changing. By dynamic I mean starting or ending the turn, everything is changing - bank angle, pitch, power, etc. The "ball" (turn & bank indicator) is sufficient for maintaining static coordination but not for dynamic coordination. The ball has a lag time in its response, so if you rely on it for dynamic coordination you will always be behind the airplane. And your eyes will be down in the panel instead out the window where they belong.

Two suggestions for this. First, the Mark VII butt-o-meter. If you learn what being coordinated feels like (or alternately, what not being coordinated feels like), you can maintain it without fixating on the ball. In a turn, any G forces you feel should be pushing you straight back into your seat. If it pushes you outside the turn (like a turn in car) you have too much rudder / not enough aileron. And vice versa.

Second, using distant horizon references. In straight & level flight, point the airplane at a prominent distant landmark like a mountain. As you bank into a turn, watch how the nose/cowling moves with respect to that landmark. This enables you to see the effect of adverse yaw. If you maintain dynamic coordination while rolling into the turn, the airplane will rotate and the nose will not shift left or right relative to the landmark, but remain in a fixed spot. If you are not coordinated, you will see the nose shift left or right as you enter the turn. For example if you enter the turn with aileron only, no rudder, the nose will shift opposite or away from the turn (adverse yaw). The idea is to enter the turn using the ailerons and use just enough rudder to prevent the nose from shifting relative to the distant landmark. This also has the benefit of keeping your eyes out the windshield where they belong.
 
A good way to practice your rudder use is the good old Dutch Roll. S&L, looking forward, roll 30 degrees to the right (or left) the roll the other way and back and forth. If you use the rudder properly, the nose will not swing side to side (you do not stay at the bank angle, when you reach 30, your roll back immediately).

Do this at different speeds with different amount of aileron and different bank angles. Higher speed will require less rudder for the same roll rate and bank angle. Slower speed more rudder. Higher roll rate, more rudder.

Then do them looking at the wing tip. Looking at the wing tip, if you are doing to wrong, the tip will appear to move forward and backwards.
 
... Then do them looking at the wing tip. Looking at the wing tip, if you are doing to wrong, the tip will appear to move forward and backwards.
Yep. Or, look forward past the nose to the horizon. If you do it wrong, the nose will appear to slide left and right. If you do it right, the nose stays fixed in place as the airplane rotates (banks) back and forth.
 
Yep. Or, look forward past the nose to the horizon. If you do it wrong, the nose will appear to slide left and right. If you do it right, the nose stays fixed in place as the airplane rotates (banks) back and forth.
I said that. :D

If you use the rudder properly, the nose will not swing side to side

Doing them looking at the wing tips is an advanced exercise.
 
I flew an Alpha trainer on Wednesday, but I thought that it didn't return to neutral...
The Alpha trainer does have centering springs - so the rudder will return to neutral. But that doesn’t mean the ball will center. The alpha trainer being a “pod and boom” design doesn’t have a lot of surface area aft the CG — therefore not a lot of natural Yaw stability.
I find flying the Alpha trainer, the inclinometer wanders to the left, and to the right with no rhyme or reason.
 
Today I was more attentive to the rudder. When rolling in or out I was using the pedals. It was much better for coordination. Lots of great guidance here, thank you flying community.
 
Closest I came to being killed as an instructor was a 24,000 hour 747 Captain.

He needed to get to a meeting, and it was quicker and easier to just have me ride along rather than getting checked out.

First take off (C-150) he firewalls the throttle somewhat rapidly, and it seems his feet were not on the rudder pedals. This was at dusk, and we did about a 45 degree left turn and headed for the trees. I added a boot full of rudder and kept us on the runway.
Please do a YouTube video, love the suspense!
 
Supposedly there is a feel for the rudder whether you are coordinated or not, I still can’t “feel” it but I can look at the turn coordinator now and then to correct it. Usually I fly in cruise with no rudder anyway.
 
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