Storch Flaperon Issues

[synjin]

So, I built a Storch and am enjoying it. Wanting it to fly slower (yeah, I know, it's already really slow), I programmed flaperons...I think. I have a FlySky Nirvana NV-14 and OpenTX is still new to me. The flaperons seem to work the way that they're supposed to, but on the landing setting the roll and turn rates are almost nonexistent. I recall Josh B. mentioning something about problems with the flaperons in one of the Storch videos and saying they'd have a video addressing this, but I can't find it. Something about needing to have the aileron go up more than going down.

Any advice?

 

[Hondo76251]

Flaperons are always tricky. Any more I just go with traditional flaps. It takes me less time to build flaps than to dial in the mixes for flaperons.

Having said that, you have the right idea. To get them to work you need to have a mix set so that the ailerons only go up, not down farther, when you induce a roll with "flaps" engaged. I ended up with a ton of mixes for each flap setting to get it how I wanted. I use spektrum so I'm not much help on the transmitter you have...

 

[Merv]

......Something about needing to have the aileron go up more than going down.

What your talking about is adverse yaw. To avoid it up up aileron must go up more than the down one goes down. The down aileron produces drag which is working against the yaw you are wanting.

Try reducing the amount of flaps while landing. OR try mixing in some rudder.

 

[synjin]

I'm kind of thinking that I'll just go with flaps. Just means I have to pull the wing off and do a bit of cutting.

 

[Hai-Lee]

So, I built a Storch and am enjoying it. Wanting it to fly slower (yeah, I know, it's already really slow), I programmed flaperons...I think. I have a FlySky Nirvana NV-14 and OpenTX is still new to me. The flaperons seem to work the way that they're supposed to, but on the landing setting the roll and turn rates are almost nonexistent. I recall Josh B. mentioning something about problems with the flaperons in one of the Storch videos and saying they'd have a video addressing this, but I can't find it. Something about needing to have the aileron go up more than going down.

Any advice?

The more up than down on the ailerons/flaperons is something called "Differential". The reason for its need is that the control surface produces far more drag when it lowers than when it raises. Without differential there is an unexpected yaw aspect to the control operation and the yaw at slow speed can actually cause a wing stall and an apparent control reversal as the wing with the lowered control surface slows and rather than producing more lift actually stalls and loses all lift! Result roll and crash!

The less effective control at slower speed is a function of the lower speed airflow over the control surfaces. The tail control surfaces can maintain good control due to the prop wash when the motor is swinging the prop. So to gain best control at low speed land with the motor still turning and use sufficient rudder to counter loss of roll control effectiveness and the Yaw effects of poorly set differential.

Without rudder usage a real slow landing is extremely difficult whereas with adequate rudder usage and enough throttle you can almost land on a dime!

The above is part of what I teach my students when they start on STOL and flap equipped models.

Have fun!

 

[Hondo76251]

I'd definitely go flaps myself. You can get flaperons dialed in to work pretty well, eventually... but I dont think they ever work as well as flaps...

 

[synjin]

It's easy to do flaps on the Storch, not so the Cub...though I haven't tried the Cub with flaperons yet. 0 degrees and below here in the Northland. Beautiful skies in January and February mean ugly temperatures. Sigh.