Which Flight Control Turns The Plane?

Well, he DID use the aileron to start the turn. I didn't see him make an "elevator only" turn.
 
A pilot cannot really make an airplane turn.

It has to want to turn.
 
Dan Thomas said:
Lesson #1: if the controls feel funny, shut down and get things looked at. Do not take off. Optimism cannot create safety.
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if one Accident isn't enough to emphasize it, here is another. unfortunately this one was Fatal, but the telling part is "the pilots shut down the engine on the runway, the instructor got out and inspected the airplane, then boarded the airplane again and the pilots subsequently departed."

EDIT:Fixed link
https://aviation-safety.net/wikibase/233164

Brian
 
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Dan Thomas said:
Lesson #1: if the controls feel funny, shut down and get things looked at. Do not take off. Optimism cannot create safety.
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Unfortunately it sometimes takes a few “events” to learn that when the airplane talks to you, you should listen.
 
Daleandee said:
"It only does that on the ground."

/sarc
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I did disagree with the Chief Pilot when he said changing the oil to winter weight would resolve the loss of oil pressure I had in flight. He finally agreed when I drained the oil and it looked like metallic paint. :rolleyes:

I will not, however, recount events leading up to the loss of oil pressure, as I might pear to be REALLY, REALLY stupid.:p
 
brcase said:
if one Accident isn't enough to emphasize it, here is another. unfortunately this one was Fatal, but the telling part is "the pilots shut down the engine on the runway, the instructor got out and inspected the airplane, then boarded the airplane again and the pilots subsequently departed."

file:///C:/Users/brcase/Downloads/Report_ANC20FA024_100980_4_6_2022%209_24_59%20AM.pdf

Brian
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Link doesn't work.
 
That's because his link is to a local file on is computer.
 
I had an instructor who liked to ask, if you have the plane trimmed perfectly for level flight and you add throttle, without making any other input changes, what does the plane do? Most people say it speeds up. The answer is, it slows down, at least for awhile. You add power, the nose goes up, the plane slows down. If you pull power, the nose drops and it speeds up. I was never really amused.
 
This is the problem with trying to oversimplify things.
 
Lowflynjack said:
I had an instructor who liked to ask, if you have the plane trimmed perfectly for level flight and you add throttle, without making any other input changes, what does the plane do? Most people say it speeds up. The answer is, it slows down, at least for awhile. You add power, the nose goes up, the plane slows down. If you pull power, the nose drops and it speeds up. I was never really amused.
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That will depend on the trim of the airplane. If the CG is aft, little stabilizer/elevator downforce is needed and adding power might not raise the nose much at all.
 
If you fly a light sport plane you can blame it on the wind ... :)
 
The short answer is None. The flight controls don’t turn the airplane, with a couple obscure exceptions.
The Wing turns the airplane.
The Flight Controls are just Angle of Attack Modifiers. The Elevator is the control that most affects the Wing AOA, and thus most affects a turn.
The point of saying the Elevator Turns the airplane is really just to initiate a discussion of understanding what the flight controls really do.

Brian
CFIIG/ASEL
 
I know rolling the wings turn the nose of the plane to a new heading. I know it does this by providing lateral thrust when wings are tilted - horizontal component of lift.

Must confess though I’m not visualizing how that works. It would seem the lateral thrust would move the track left or right.

If the center of lift is forward of the CG then I can “see” how that works, as it would pivot around the CG.

How however does it still work when the CG is forward of the center of lift? Maybe that would be an un flyable configuration?
 
WDD said:
I know rolling the wings turn the nose of the plane to a new heading. I know it does this by providing lateral thrust when wings are tilted - horizontal component of lift.

Must confess though I’m not visualizing how that works. It would seem the lateral thrust would move the track left or right.

If the center of lift is forward of the CG then I can “see” how that works, as it would pivot around the CG.

How however does it still work when the CG is forward of the center of lift? Maybe that would be an un flyable configuration?
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As we mentioned before, the tailfeathers line the nose up with the track. Mostly. You'll see a slip unless you add some rudder and elevator. The airplane is a dart. Or an arrow. The feathers make it track straight.
 
Personally I believe it's not any particular control and yet it is all of them. As was said early on, the horizontal lift component. Simply stated the airplane turns because it is banked. There are many ways to make the airplane bank. Once banked the elevator is needed to maintain a level turn. :dunno:
 
EdFred said:
Oh man, not this again. He's also wrong. What happens with plane that has no elevator? It can't turn? I can lock the elevator and it will turn.
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EdFred said:
Oh man, not this again. He's also wrong. What happens with plane that has no elevator? It can't turn? I can lock the elevator and it will turn.
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I think there is a lot of confusion over primary and secondary effects of the flight controls.

The ailerons - primary function is to set the rate of turn — they do not turn the airplane. Secondary fx is adverse yaw.

Rudder - overcomes adverse yaw or yaws where needed (slips). Secondary fx is wing roll.

Elevator - adjusts AOA and wing loading of the main wing. When you point your lift vector sideways this pulls aircraft thru turn. This is what he clearly demonstrates and explains in the video.

One can be more granular but we are flying airplanes not engineering them. On that note, POHs show increasing stall speeds with bank angle increases. Those charts assume maintaining level flight (back pressure or trim) which is what increases the stall speed, not the bank angle.

I think this misconception leads people to fear turns close to the ground, do bad things with their feet and elevator due to a fundamental misunderstanding of what the flight controls actually do. The control input that saves your life in that context is the elevator. Unloading back pressure thus lowering the AOA and wing loading.

A vertical loop is a turn at zero angle of bank.
 
Sky Review said:
One can be more granular but we are flying airplanes not engineering them. On that note, POHs show increasing stall speeds with bank angle increases. Those charts assume maintaining level flight (back pressure or trim) which is what increases the stall speed, not the bank angle.

I think this misconception leads people to fear turns close to the ground, do bad things with their feet and elevator due to a fundamental misunderstanding of what the flight controls actually do. The control input that saves your life in that context is the elevator. Unloading back pressure thus lowering the AOA and wing loading.
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There's some confusion there. The stall increases with bank angle, as long as we're coordinated and not slipping. Lowering the nose ONLY BRFIEFLY decreases the stall speed in a bank as long as the nose keeps dropping and the load factor is held below the level-flight factor. So you have to keep the nose dropping until the airplane is in a vertical dive.

Any steady flight state will be at a constant load factor. Straight-ahead, whether level, climbing or turning, is essentially 1G. A level turn will be at a given load factor; just letting the nose drop into a descent won't lower it indefinitely. At a steady rate of descent in the turn, at a given bank angle, will be the same load factor as the level turn.

Astronauts train for zero-G by flying in an airliner with no seats in it. The pilot gets it into a climb, then pushes over so that the load factor drops to zero. He has to keep pushing, and the airplane curves over the top and goes into a steadily steepening dive, meaning that the astronauts only get a few seconds of zero-G. The pilot has to recover or crash.
 
Sky Review said:
The ailerons - primary function is to set the rate of turn — they do not turn the airplane. Secondary fx is adverse yaw.
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The ailerons do not control rate of turn. Where did you read that?

Sky Review said:
On that note, POHs show increasing stall speeds with bank angle increases. Those charts assume maintaining level flight (back pressure or trim) which is what increases the stall speed, not the bank angle.
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No, it assumes 1g of vertical lift component. A 45° bank at 1g total lift would result in a reduction in the vertical component of lift by 29%, and a descent rate of 5,600 fpm after only 10 seconds (29% * 32f/s * 10s * 60s/m).
 
Sky Review said:
Elevator - adjusts AOA.
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This should have been the end of the answer. If the lift vector is tilted, a turn may result, but elevator is neither necessary nor sufficient to turn. Once again, oversimplification leads to misunderstanding. If you fix (i.e. 'freeze') the elevator, roll so the wings are at, say, 45 deg angle of bank, and add power, will the airplane turn? Hint: Yes. Try it. Why? Because increasing airspeed also increases 'the horizontal component of lift', which turns the airplane. If you pull back on the stick, er, yoke, but reduce power does the airplane turn? Which way? Depends on how much of each you do - a little aft stuck and a big power reduction will result in a steady descent, not a 'turn.' The oversimplification would lead one to believe that the rudder-only model in post #3 of this thread cannot turn, and yet...

Nauga,
who tries to make it easy, but not necessarily simple.
 
If the goal of this exercise was to clarify the understanding of how an airplane turns it has failed miserably.
 
Actually at 1000 pounds or so gross weight, differential heating caused by the earth's rotation causes an airplane to move on all three of its axis...
 
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