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Thrustline, Real world

My latest wings from Jay are 1.5 from memory but i measured them to the window/ door sill and didn’t get any difference. I’m a bit confused. I’ll check with jay again. The fuse is standard like yours I think.
 
Colin,
I think I know where the confusion is.
Angle of incidence is the relationship of the chord line to the longitudinal axis.
The chord line is the imaginary straight line joining the leading and trailing edge of an airfoil.
On the USA 35B airfoil of the Cub, the chord line relationship to the lower surface of the airfoil is approximately 1.5 degrees.
So when it is said that a Cub's angle of incidence is 1.5 degrees, that would place the lower camber of the airfoil parallel to the longitudinal axis.

iu

iu
 
Pete’s elevator trim explanation is the first coherent explanation I have seen. Normally it is better to have the prop arc perpendicular to the relative wind for any given operation.
 
I know I am a bit dense, but the last sentence does not make sense! The lower camber of the airfoil (lower surface of the wing) is not parallel to the chord line. You can see that on the cartoon. What am I missing?

Colin,
I think I know where the confusion is.
Angle of incidence is the relationship of the chord line to the longitudinal axis.
The chord line is the imaginary straight line joining the leading and trailing edge of an airfoil.
On the USA 35B airfoil of the Cub, the chord line relationship to the lower surface of the airfoil is approximately 1.5 degrees.
So when it is said that a Cub's angle of incidence is 1.5 degrees, that would place the lower camber of the airfoil parallel to the longitudinal axis.

iu

iu
 
I know I am a bit dense, but the last sentence does not make sense! The lower camber of the airfoil (lower surface of the wing) is not parallel to the chord line. You can see that on the cartoon. What am I missing?
Look again. This is about a Cub not the drawing.
"So when it is said that a Cub's angle of incidence is 1.5 degrees, that would place the lower camber of the airfoil parallel to the longitudinal axis."
 
Thinking about the power off question I can only guess that the mod works the same. I know from changing pitch on a prop on my Clipper I was surprised at the thrust from an idling prop and the difference between the two pitches so it only make sense that it would work at low power as well.

Bottom line, some of y'all are way smarter and think way more than I do. I listen to the people I trust and luckily I get to fly the mods before and after on other people's airplane. I bolt them on mine which I am intimately familiar with and see what difference it made. The problem is after a while it gets to be the norm and I am always wanting more. Once I get use to it I don't realize what I have until I fly someone else's unmodified Super Cub and then it is like wow again. It is like Crack, I just keep wanting more. I don't always know the science of why something works, I just know it does in the seat of my pants.
 
Look again. This is about a Cub not the drawing.
"So when it is said that a Cub's angle of incidence is 1.5 degrees, that would place the lower camber of the airfoil parallel to the longitudinal axis."

By "lower camber of the airfoil" you mean bottom of the wing. correct?
DENNY
 
My latest wings from Jay are 1.5 from memory but i measured them to the window/ door sill and didn’t get any difference. I’m a bit confused. I’ll check with jay again. The fuse is standard like yours I think.

Are you talking washout (twist)?
DENNY
 
It worked on my Cub. Been flying with it since Mark first started with it.
You cant have it back, Mark.

Thanks Bill! Pretty sure you were the first. I will never forget that trip and your help. Those were fun times. Sorry to hear about Daryl. What a character,he will be missed!
 
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