Opposite rudder in a steep turn

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woxof

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woxof
Somebody posted on another forum that while most aircraft can do a coordinated turn with rudder neutral or sometime some rudder input in the direction of the turn, on occasion, some opposite rudder is required to be coordinated perhaps due to a particular design or even the quirks of a specific airframe.

Has anybody seen this?
 
ball inna center is what I was taught. (Unless you are talking about aerobatics, of which I know less than nothing)
 
Some folks use opposite rudder to neutralize the overbanking tendency, but the ball will be to the inside. It's usually a bit of opposite aileron that's required in a coordinated steep turn.
 
Never thought about it, but one definition of a steep turn is a turn so steep overbanking becomes an issue. So, a pilot has to hold a bit of aileron against the turn to avoid overbanking. In that case it makes sense a tad off opposite rudder might be needed to counter adverse yaw.

But it’s not something I’ve ever noticed. More common is too much “top” rudder to keep the nose from dropping, which results in slipping.

(I see Dan expressed much the same while I was composing this.)
 
Logically speaking:

In a 45 degree steep turn opposite rudder will hold the nose up just as well as elevator. Steeper than that the rudder will work better to hold the nose up than elevator.

I’m oversimplifying and not suggesting you do this, just pointing out the physics.
 
woxof said:
Somebody posted on another forum that while most aircraft can do a coordinated turn with rudder neutral or sometime some rudder input in the direction of the turn, on occasion, some opposite rudder is required to be coordinated perhaps due to a particular design or even the quirks of a specific airframe.

Has anybody seen this?
Click to expand...
For sure when thermaling in a glider.
 
Salty said:
In a 45 degree steep turn opposite rudder will hold the nose up just as well as elevator. Steeper than that the rudder will work better to hold the nose up than elevator.
Click to expand...
And if it's a V-tail? One of the control surfaces becomes purely a rudder and the other purely an elevator?
 
FastEddieB said:
Never thought about it, but one definition of a steep turn is a turn so steep overbanking becomes an issue. So, a pilot has to hold a bit of aileron against the turn to avoid overbanking. In that case it makes sense a tad off opposite rudder might be needed to counter adverse yaw.

But it’s not something I’ve ever noticed. More common is too much “top” rudder to keep the nose from dropping, which results in slipping.

(I see Dan expressed much the same while I was composing this.)
Click to expand...
I believe you nailed it.
 
Salty said:
Logically speaking:

In a 45 degree steep turn opposite rudder will hold the nose up just as well as elevator. Steeper than that the rudder will work better to hold the nose up than elevator.

I’m oversimplifying and not suggesting you do this, just pointing out the physics.
Click to expand...
While I understand your theory, I’m not so sure it works that way... and I would not teach it that way.
 
Holding an established, coordinated turn with a 20-degree bank, most airplanes require no rudder at all. Holding a turn with a 90-degree bank, every airplane will require a whole ton of opposite (“up”) rudder. In between, some will and some won’t.
 
Salty said:
Logically speaking:

In a 45 degree steep turn opposite rudder will hold the nose up just as well as elevator. Steeper than that the rudder will work better to hold the nose up than elevator.

I’m oversimplifying and not suggesting you do this, just pointing out the physics.
Click to expand...

I’ll say “just as well” only applies if you ignore the monstrous slip the plane will be in. Which is both uncomfortable and inefficient.
 
Rudder as needed to maintain coordination in the turn in the wind and with the load and CG you’re flying with that day.
 
In the olden days, we called it "top rudder".
I judge all instructors with one question: "What is top rudder?"
If they don't know, they are done.
 
And when used to alter the rate of the turn? It’s a great way to get into a spin.

For review-
 
Kritchlow said:
While I understand your theory, I’m not so sure it works that way... and I would not teach it that way.
Click to expand...

27SuC.jpg
 
FastEddieB said:
I’ll say “just as well” only applies if you ignore the monstrous slip the plane will be in. Which is both uncomfortable and inefficient.
Click to expand...
Nobody ever reads the disclaimers
 
turbulence. that’s what happens when you’re surrounded by mountains.
 
Right rudder in a right steep turn, no rudder in a left steep turn works to center the ball in most planes I've flown.
 
dtuuri said:
With a little more rudder, it can be turning in the opposite direction. But then, the OP said "coordinated turn".
Click to expand...
Good point on the quoted part. Don’t understand the first part. With more down elevator you could turn the other way. Lol
 
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Salty said:
Don’t understand the first part.
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The OP was talking about top rudder in a turn in one direction, but with too much top rudder the turn changes direction and isn't "opposite" rudder anymore. Some pilots might think that's impossible to do, at least under positive g's, e.g., bank left, turn right, but it is easily done in a shallow bank. But then, again, the OP said "coordinated turn".
 
Of course turbulence will require control input to compensate. I just thought it was being implied that wind routinely affected the amount of rudder needed in a steep turn.

Now that that’s been cleared up, back to your regular programming...
 
OneCharlieTango said:
Holding an established, coordinated turn with a 20-degree bank, most airplanes require no rudder at all. Holding a turn with a 90-degree bank, every airplane will require a whole ton of opposite (“up”) rudder. In between, some will and some won’t.
Click to expand...

How many Gs is 80 degrees of bank? What are the limits for normal, utility, and acrobatic category aircraft?
 
Stewartb said:
turbulence. that’s what happens when you’re surrounded by mountains.
Click to expand...
I must say I fly by this. Nothing worst than flying down a channel/valley than winds rolling off mountains. Mechanical turbulence is localized and can really get your attention.
 
What is this ball you guys keep mentioning? I just try and keep the moving bottom of the triangle under the top part. I’m just a crappy GA pilot so all this 90 degree bank stuff scares me. I figure if I maintain the triangle at all times except maybe in a crosswind landing, I’m less likely to die. That and keep the flight path marker inside the rectangles, the little plane on the magenta line in the moving map, my plane away from the diamonds on the traffic display and away from the red blotches on the radar display I should be good. Someday I might even get to look outside the windscreen.
 
dmspilot said:
Right rudder in a right steep turn, no rudder in a left steep turn works to center the ball in most planes I've flown.
Click to expand...

Airplanes love to turn left but need encouragement to turn right. (No CCW rotation comments, please.)

Bob
 
AKBill said:
I must say I fly by this. Nothing worst than flying down a channel/valley than winds rolling off mountains. Mechanical turbulence is localized and can really get your attention.
Click to expand...

So true. Owens Valley on the leeward side of the Sierras sucks, 'specially in the afternoon. If I fly to Bishop/Mammoth again, it's gonna be in the morning...stay overnight...fly back the next morning!
 
FastEddieB said:
Almost 6 g’s:

lesson9figure01.gif
Click to expand...

And the positive load ratings are what value? On the bank thru 84 degrees the positive load limit of a normal category aicraft is exceeded by 236%, 200% in a Utility Category aircraft, and 50% in an Acro category aicraft.

I doubt being out of coordination is a big factor when you are about to tear the wings or tail off.
 
bobmrg said:
Airplanes love to turn left but need encouragement to turn right. (No CCW rotation comments, please.)

Bob
Click to expand...

Anyone notice all (Reno) pylon races turn left?
I can't think of any, other than the Red Bull races, where they turn to the right.
 
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