How do airplanes turn?

[Almerick07]

I know a guy who just busted his CFI checkride with the OKC FSDO. Appearantly the examiner told him he was a student pilot and to tell him how the ailerons turned the airplane. The guy gave a pretty simple answer but the examiner wanted to hear, "the aileron changes the camber of the wing."

Not only does this sound a little fishy, but I know that isnt how I would explain a turn to a student pilot...makes me wonder about these FAA guys.

How would you (CFI) explain a turn to a student pilot?

 

[mynameisjim]

I would answer "how an airplane turns" differently then how I would answer "how does an aileron lift a wing".

How was the question asked?

 

[Tarzan]

An aileron does not change the camber of a wing. They change the angle of attack. The effect is a banked airplane resulting in a horizontal compentent of lift. Your buddy'd CFI didn't teach him very well.

 

[minitour]

Moving an aileron up and/or down changes the chord line of the wing. Chord line and relative wind gives you angle of attack. So assuming the same relative wind, you changed the AOA...change in AOA, change in lift...wings move up/down plane turns.

-mini

 

[VNugget]

An aileron does not change the camber of a wing. They change the angle of attack.

It changes both.

 

[MyRadarIsOut]

How do airplanes turn?


Very Carefully

 

[NookyBooky]

I know a guy who just busted his CFI checkride with the OKC FSDO. Appearantly the examiner told him he was a student pilot and to tell him how the ailerons turned the airplane. The guy gave a pretty simple answer but the examiner wanted to hear, "the aileron changes the camber of the wing."

Not only does this sound a little fishy, but I know that isnt how I would explain a turn to a student pilot...makes me wonder about these FAA guys.

How would you (CFI) explain a turn to a student pilot?

I don't know, but I bet George W. Bush is behind this somehow.

 

[HAL]

The question from the examiner was bull. Ailerons do not turn the plane - they change the lift of each wing to roll the plane around the longitudinal axis. Turning requires coordinated use of ailerons, elevator & rudder.

It sounds to me that the examiner was looking for a reason to fail this guy. It happens, especially in CFI checkrides. They have to keep their failure rate up to look good to their bosses.

HAL

 

[learflyer]

Flight options acft sometimes quick turn in 8-10 mins. Depending on how quick the line guys are.

 

[mzaharis]

It increases circulation, to account for the Kutta condition on a modified flow field.

 

[Pilot_Ryan]

The elevator is primarily responsible for turning - as in, changing the flight path - of the airplane. I doubt the examiner would have the veracity to comprehend the true meaning of that statement.

 

[FN FAL]

How do airplanes turn?

How would you (CFI) explain a turn to a student pilot?

It's pretty simple. Planes turn because a pilot's ego makes the earth pivot about his axis. I don't know how chick pilot's do it, but...

 

[Tarzan]

It changes both.

Whatever. Go look up the definition of camber. It's how the wing is shaped. The only way to change camber is through wing warping, akin to how the Wright Brothers did it.

 

[mzaharis]

Whatever. Go look up the definition of camber. It's how the wing is shaped. The only way to change camber is through wing warping, akin to how the Wright Brothers did it.

Warping only changes the AoA of the wing at various points along the span. The camber (the displacement of the centerline of the wing cross section, or mean camber line, from the straight line connecting the leading and trailing edges) does not change in wing warping.

Here's another definition of mean camber line:

"The mean camber line shown in this illustration is the line that is equidistant at all points between the upper and lower surfaces of the airfoil. The mean camber line shown in this illustration is the line that is equidistant at all points between the upper and lower surfaces of the airfoil. "

I'm posting an interesting link that discusses the definition of camber:

http://www.centennialofflight.gov/essay/Evolution_of_Technology/airfoils/Tech5.htm

By that argument, aileron deflection does change the camber of the wing (at least the section whose chord line crosses the aileron), as it changes the mean camber line. It also changes the angle of attack, by changing the straight line connecting the leading and trailing edges.

 

[CRJDog]

Just treat them nice and she won't turn on you.