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Improved aileron control at low speed. Discussion/solutions?

Yesterday I visited with one of our members who has a nice aluminum spar J-3 with corrosion on aluminum wing tip bows which need repair. He is considering squaring the wing tips with one of the available modifications.

Do any of you know of an approved aileron modification for squared wings which removes the section of aileron which is inboard of the control horn hinge along with the inboard hinge? Then moves this removed section to the outboard end of the aileron. This will retain the original aileron size and shape with the effect of moving the aileron force moment further outboard thus increasing roll authority at low speeds.

This must be FAA approved, either an STC, field approval or something else. It may have been approved on any Cub type long wing. Any ideas??
 
Sullivan STC squared the wing and lengthened the aileron out to the tip. Dakota Cub sells a wing where the stock length aileron is moved out to the tip of a squared wing and the flap is lengthened to take up the extra space. Probably doesn't help with a J3 but that is what I know of.
 
Put an ash bow on there, and keep it stock? Keep its value up? J3s fly just fine in stock configuration with a little horsepower boost. Mine flies fine at stall with a little power.

If you mean the spars are corroded at the tip, come to my hangar and I will give you enough spar tips for one wing. I cannot imagine enough corrosion on that part of the spar without having the same problem elsewhere. Dakota makes really good spars for cheap.
 
How are pacer/tripacer ailerons and rudder interconnected?

The rudder and aileron cables are linked by small sections of cable. The interconnect cables are swaged at each end onto the rudder and aileron cable that should move together. They are visible behind the aft baggage area. In the middle of each interconnect cable is a spring that allows the pilot to overcome the connection.
 
The rudder and aileron cables are linked by small sections of cable. The interconnect cables are swaged at each end onto the rudder and aileron cable that should move together. They are visible behind the aft baggage area. In the middle of each interconnect cable is a spring that allows the pilot to overcome the connection.

And lots of pacer and tripacer owners loosen up that interconnect so it flies like a real airplane.


Sent from my iPad using Tapatalk
 
This must be FAA approved, either an STC, field approval or something else. It may have been approved on any Cub type long wing. Any ideas??

for -12 wing, sullivan(Day & Night, now Aircraft innovations brand?) also had add LONG flaps(which are made from cub ailerons) then moved ailerons out and shortened them like~13" squaring the wing in the process.... have seen it on -18 wings but not sure who/how...
 
I vote VGs too. If you dont notice a difference your probably not flying the plane in the profile where they come into play. Simplicity and $, it can't be beat.
 
Pete, you pose an interesting question, and it makes me think about adverse yaw. When you're slow aren't you typically nose high, and doesn't one typically need to use lots of rudder to counteract adverse yaw? I wonder, if someone wants more aileron for more roll, don't they also want more rudder? Maybe they don't even need more aileron - maybe they need to use their rudder more. It's been my observation that when pilots get slow and want to turn that they use the aileron but very often forget the rudder (and I'm quite guilty of this myself), so my thought would be to confirm that the person wanting more aileron first ensures that he's using the rudder.
In looking at this old thread, I noticed this comment from Speedo on adverse yaw. I agree with him on rudder use. Many, if not most pilots are lax in their rudder use. Particularly those who learned to fly in more modern airplanes which have had most of the adverse yaw engineered out of them. Adverse yaw, the tendency of the nose to move opposite of the direction of aileron induced bank, is caused by the drag of the down aileron. This brings the question, would there be less adverse yaw if there was less aileron area or span to generate that yaw force? A stock Cub aileron has 102-1/8" of span (length). My ailerons in these photos have 83-1/4" span. There is adverse yaw in this Cub, but not enough to noticeably require a lot of rudder to compensate. This Cub has never indicated to me that it lacks roll control effectiveness at low speeds. Also you'll notice there is a gap seal on the right aileron and none on the left. I did this to attempt to determine if there would be more or less roll control in one direction or the other. I could find nothing. I didn't bother to remove the gap seal nor to add the other. Also this wing has a smooth clean leading edge. One thing which I attribute to the smooth and adequate roll response is ball bearings in all the pullies and tight aileron cables. When the cables are flown loose in order to lighten the stick forces, the first motion of the stick is only taking up the slack in the cable. And because of this, there is not enough stick travel to pull the aileron to it's stops. Thus less than desired roll control effectiveness.

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Gap seals the same as on the flap does help the aileron response.

Robertson Stol kit's on Cessna's doo aileron gap seals as well.

We have experimented with VG's on the flaps with very good results , but I would be more cautious on Ailerons.
 
Gap seals the same as on the flap does help the aileron response.

Robertson Stol kit's on Cessna's doo aileron gap seals as well.

We have experimented with VG's on the flaps with very good results , but I would be more cautious on Ailerons.

The Robertson kits on the 180/185 have an aileron gap seal. The RSTOL kit for the 206 does not....very different aileron.

MTV
 
We have experimented with VG's on the flaps with very good results , but I would be more cautious on Ailerons.
Where did you place the VGs on the flap and are your flaps the stock length?

The gap seals on the 180/185 are necessary because a wider hinge is installed to move the aileron further from the trailing edge of the wing in order to make enough room to get the desired droop. This leaves a big gap between the wing trailing edge and the leading edge of the aileron which must be filled. Without this wide hinge, the aileron is restricted from the desired droop. The 180/185s could use better aileron control.
 
We have experimented with VG's on the flaps with very good results , but I would be more cautious on Ailerons.
I too would like to hear about these results.
I’ve pondered adding VG’s to the front curve of the flaps, where they would “roll out” at the last notch or two of flaps, and otherwise would be in the cove not affecting airflow. To do this meant not having a good gap seal there.
 
I too would like to hear about these results.
I’ve pondered adding VG’s to the front curve of the flaps, where they would “roll out” at the last notch or two of flaps, and otherwise would be in the cove not affecting airflow. To do this meant not having a good gap seal there.
A proper gap seal on the flaps is the same as a slot on the leading edge of the wing. The flap gap seal prevents flow separation on the flap which I have proven with yarn tassels. You don't have the gap on your Patrol flaps unless you have made an alteration.
 
Pete you’re saying that there is no separation on nearly 50 deg of flaps on the 9’ barn door flaps of a Patrol? I find that hard to understand?
With the AOA I see prior to losing lift I can’t imagine the air sticking to a near vertical flap surface at attitude.
 
Pete you’re saying that there is no separation on nearly 50 deg of flaps on the 9’ barn door flaps of a Patrol? I find that hard to understand?
With the AOA I see prior to losing lift I can’t imagine the air sticking to a near vertical flap surface at attitude.
A miscommunication. I assumed Dog was talking about a Piper slotted flap. Your Patrol's hinged flaps are a different story. I do expect a flow separation there and it's possible that placing VGs on the forward edge of the flap may help.

Notice how the air flows over the top of the wing. When the angle of attack nears the stall, the air becomes turbulent/cloudy and reverses direction. When it gets cloudy and reverses direction the drag exceeds any lift advantage. Look at the wings with different flap configurations. The slotted flap seems to provide the best lift over drag function. The Patrol has hinged flaps which loose their lift at lower angles of attack than the slotted. In all cases the airflow separation which starts at the trailing edge is controlled by what effects the airflow over the leading edge.


Your Patrol wing will require some investigation. Just off the top of my head, it appears that VGs on the wing leading edge and VGs on the flap at the most forward location might help hold the air to the top of the flap at higher angles of attack. If it were me, I would experiment with VGs on one flap first....after the plane has flown for a few hours. Put on your test pilot hat......approach with caution. After you learn about the flap VGs, you can try adding them to the leading edge of the same wing. Remember to approach all this with caution. If the VGs have an effect, one wing will have more lift than the other as well as different stall characteristics. First flight will be flaps up to altitude. We can talk about this if you wish.

This is another with a flapless wing.

 
Previously.....flaps, ailerons, seals, VG's, and Circulation Theory. The last typically is another method to explain how wings produce lift.


Gary
 
VG’s on flaps.
It was done without gap seals on a experimental Pacer/bushmaster, it dropped the stall speed considerably at full flap Settings but I personally did not like the feel without gap seals and no flap. Vg’s were just slightly back of the leading edge of your flap so they are right in the airflow that that gets directed over them from the gap seal. Using the plastic VG’s that can be trimmed if needed. I never did fly this Configuration with the seals installed on that plane but we looked at it there was enough clearance.

The last sportsman kit we installed (C 175) also had aileron gap seals so that is a common mod coming allong with Stol Mods on Cessna’s
 
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One caution with deep STOL mods....make sure rudder, elevator, and stabilizer control remain effective at all airspeeds and CG. That's far easier to say than do without some practice at safe altitude. Certification Standards can describe the required tests.

Gary
 
One caution with deep STOL mods....make sure rudder, elevator, and stabilizer control remain effective at all airspeeds and CG. That's far easier to say than do without some practice at safe altitude. Certification Standards can describe the required tests.

Gary
I second that thats where gap seals VG's on the tail and ailerons come in.

Micro VG's did respond to that many years ago with VG's on the tail.
 
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