Citabria Ailerons Extremely Stiff over 90 MPH?

Joined
Apr 24, 2021
Messages
4
Location
Forest Twp, Maine
I have a 72 Citabria w/ O-235 and wood spars. When I get up to cruise, over 90 MPH or higher, Ailerons get Extremely Stiff. They go from about 5 lbs of pressure to move the stick right or left at below 90 mph, to about 20 lbs of force at higher speeds. Really a drastic change. I know it should get harder the faster you go, but this is not right!!! Any ideas? Rigging? Drag/Anti Drag Wires letting wing move in higher speed flight? Max speed in level flight is 110 mph @ wide open (2600 RPM) and only when I lean it aggressively.
 

Hiperbiper

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May 30, 2020
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180
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Shreveport Louisiana DTN
Check the ailerons when centered. They should have a slight droop when static. I've seen people reflex the ailerons both "up" to supposedly get a higher top speed...it doesn't really work but it will cause the ailerons feel funny.
Also, check the tension on the aileron cables, pulleys and look for rubbing against ribs or compression tubes.
Just some cursory things to look for...

Chris
 
Joined
Apr 24, 2021
Messages
4
Location
Forest Twp, Maine
Howdy,

My mechanic and I opened up the wings, checked cable tension, binding, rigging and such. Found nothing out of the ordinary. Talked to a fella who once owned same model and vintage of plane, and stated that it is the nature of the beast.

He said he put some Aileron Spades on the plane and worked wonders, even with wood spars.

Anyone know where to get a set of spades and a STC for installation?????

Going to try a fish scale on the stick at various speeds to doccument findings and compare to other aircraft. But really leaning on trying a set of spades.

Cowboy in Maine
 

aftCG

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Apr 3, 2018
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480
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Tacoma, WA
You can find spades on eBay right next to the unicorn saddles. Paperwork is the road block since you can't transfer the STC. That said, they are fantastic.

Control feel is out of whack on this airplane with stick forces in roll being the one that gets your attention. The first time I flew my Citabria was the first time I flew one without spades and as I accelerated out of the pattern I had that WTF moment where I thought something was wrong.

For peace of mind I would triple check the cable runs and pulleys. See if you can get a couple of helpers to reflex those ailerons slightly upward (as if they're getting a flight load) and try the feel then. It might highlight a tight pulley or something.
 

Bartman

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Mar 27, 2018
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New Jersey, USA
Howdy,

My mechanic and I opened up the wings, checked cable tension, binding, rigging and such. Found nothing out of the ordinary. Talked to a fella who once owned same model and vintage of plane, and stated that it is the nature of the beast.

He said he put some Aileron Spades on the plane and worked wonders, even with wood spars.

Anyone know where to get a set of spades and a STC for installation?????

Going to try a fish scale on the stick at various speeds to doccument findings and compare to other aircraft. But really leaning on trying a set of spades.

Cowboy in Maine
when we were attaching my wings i mistakenly put one aileron cable over the top tubes above the headliner and one below. I would imagine that this would bind up the cables as airspeed goes up if it were left that way. the ailerons and wing are almost exactly the same as the Champ so they're a holdover from a slower time. having said that, yours still sound too heavy so continuing to look is probably a good use of your time. even at cruising speeds around 100 mph roll is out of balance with pitch but it shouldn't be that bad. around 110 to 140 the roll forces go way up.

Thanks for your post and welcome to the site!
Bart
 

Big Ed

N50247 - '79 Super D
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Jul 20, 2020
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637
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Tampa, FL
One of the original motivations for the Decathlon design was to improve Citabria stick forces, which were known to be excessive in roll.
 
Last edited:

BB57

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Feb 20, 2020
Messages
196
Check for excessive cable tension. That will increase aileron forces, over and above the already heavy forces in a non spade equipped Citabria.
 

BB57

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Feb 20, 2020
Messages
196
Actually, anything above 15# on the aileron cables is overkill as long as the pulleys in the system are free to rotate.

Chris
Agreed. If you need to keep it in the specified range you want it at 20 lbs. More will equal heavier aileron feel.