When I did steps 32-09,10, this involves locking the flaperons with a bold and having a 0.125 drop on each flaperon. I just double checked this and everything is perfect. When the left flaperon is in the neutral position, the right flaperon is dropped by ? of an inch. I thought I read some post that this is normal? Is that correct?
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Flaperon Droop Question
- Thread starter jsenft
- Start date
cactusman
Well Known Member
There was a revision on this during my build. The "Bible" aka PAP Rev 3 says (page 2-2) that the left flaperon held in line with the tip trailing edge, the right should be down 1/4-1/2 inch.
I had to do this 2-3x and double check the revision to make sure I had the spacers clamped in the right spot....also the rivets cause some confusion on this in the plans revision as if you clamp the spacers on the rivets you will create an even bigger droop I think.
I noticed on my new SLSA that when I first started flying it and put the flaps up, the flaperons would droop a little bit.
If I pushed the flap button again and pushed all the way down it would bring them up in line with the wing.
On the ground it will make a click when I do that and in the air it's obviously more streamlined and I can feel a tiny pitch change when I do it.
Don't know if this is by design or an error in rigging? Same on both sides.
If I pushed the flap button again and pushed all the way down it would bring them up in line with the wing.
On the ground it will make a click when I do that and in the air it's obviously more streamlined and I can feel a tiny pitch change when I do it.
Don't know if this is by design or an error in rigging? Same on both sides.
Why?
Because air loads in flight cause them to lift slightly.
Adjusted to a slight droop makes them actually aligned in trail, in flight.
Because air loads in flight cause them to lift slightly.
Adjusted to a slight droop makes them actually aligned in trail, in flight.
In my SLSA after raising the flaps sometimes I need to push the button and push the flap handle all the way down.
This cause the flaps to be 'fully up' as opposed to trailing slightly. And it IS only a small movement. However, there is definitely less drag as witnessed by the slight 'bump' felt as I do this.
Why would you want to design the flaperons to droop slightly and increase drag? They can only 'float up' when drooped. When I push the button and put the handle all the way down they're UP and can't go any further.
I have to say, sometimes when I fully retract the flaps I keep pushing the button to ensure they're all the way up. Occasionally, I look out and notice they're drooping and I fix it.
Just saying!
The bump you feel has nothing to do with a change in drag.
It is simply a change in trim. Any movement of the flap position causes a trim change.
As I said already, when in flight the air loads on the bottom of the (large, lots of surface area) flapperons, deflects them upward. The drooped adjustment is to compensate for that.
It is simply a change in trim. Any movement of the flap position causes a trim change.
As I said already, when in flight the air loads on the bottom of the (large, lots of surface area) flapperons, deflects them upward. The drooped adjustment is to compensate for that.
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Bill_H
Well Known Member
Read this.
http://www.vansairforce.com/community/showthread.php?t=112110
Related to an RV12 model BEFORE the discussed modification. (S/N 412 - don't know what shipping date would likely have the mod.)
http://www.vansairforce.com/community/showthread.php?t=112110
Related to an RV12 model BEFORE the discussed modification. (S/N 412 - don't know what shipping date would likely have the mod.)
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