What amount of coupling to use between elevator and flaps.
 

Greetings from Sunny Queensland. :cool:

What percentage of flap to elevator coupling do you use on your fun fly models for radical flying?

Is the flap throw 50% of elevator throw?
Is the flap throw 75% of elevator throw?
Are your flaps depressed 30 degrees when the elevators are raised 45 degrees?

Is this just a trial and error thing with every model set up differently?

I find that my models will not do a flat spin when the elevator and flaps are coupled. I can do great flat spins with the coupling switched out. (I have yet to do a climbing flat spin.)

What amount of coupling to use between elevator and flaps.
 

completely maxed out...3d throws with 70-80 expo...remeber to turn off the mix when you land.

What amount of coupling to use between elevator and flaps.
 

OUTSSIDER.. could you explain that in a little more detail? I 've been trying to hover for a couple of monthes now and can't seem to get it. I was going to post a question tonight about this. I take it you guys are not using a standard 4 channel radio? Thats what I've been using. I do have another one, Futaba T6XH, I used to try to fly a heli. What mixing should I do? Thanks, Craig

What amount of coupling to use between elevator and flaps.
 

Graeme, anywhere from 20 to 100% till you get the reaction you want.

You might want to set up another mix for spoilerons, ie. pull full up elevator and the ailerons go up also. Kills the lift on the wing some.

Its all a great experiment.
Ed M.

What amount of coupling to use between elevator and flaps.
 

Could somebody PLEASE explain this....spoilerons/flaperon thing
to me? thank you................Craig

What amount of coupling to use between elevator and flaps.
 

Craig, short version:

Flaperons - you set up a radio mix so when you pull up elevator both ailerons go down or if you push down elevator then both ailerons go up. Causes the plane to turn tighter, up to the stall point anyway.

Spoilerons - you set up another mix so when you pull up elevator both ailerons go up or if you push they go down. tends ot kill some of the lift on some planes. Sometimes used ot help stabilize a harrier or in my case I have used it on a profile to get some weird spins.

Hope this helps...............ed

Greetings from Sunny Queensland.
 

Can those people who have mastered the "climbing flat spin", please tell me if they leave the flaps and elevator coupled or not during this maneuver.

If they are still coupled, what ratio is the coupling set at?

What amount of coupling to use between elevator and flaps.
 

I use flaperons for flat spinning, but it needs to be the right %. The climbing flatspin (CFS) has to do a lot with the CG location. For the CFS the CG has to be quite on the aft side, which can compromise other flight behavior. Don't expect a rocket climbing. It would climb slowly. Be happy when you get a flatspin that just hangs there and doesn't loose altitude. Then work (giving more or less rudder or throttle for example) from there to see if you get it to climb.
As for the mixing goes, every plane is different, and requires more or less flaperons and/or spoilerns. A good starting point for me is 60% ! Then you experiment from there. Could be a little more, could also be less. Try the next flight with 70 or 80% and then the next with 50 or 40% only, and see which is the best flaperon rate for your plane, engine, prop, cg setup. You really have to dial your plane in. Could take a couple of flights.
I always like to set the CG on my profiles, so when flying inverted no or very little down elevator input is required. Once that is set, I work on my other setups such as flaperon and spoileron mix.
Hope this helps.

What amount of coupling to use between elevator and flaps.
 

Craig F.....

I don't have the mix on for hovering ....although it probably wouldn't make much difference.

to make hovering as easy as possible you need several things..

1....cg as aft as you can stand it
2...big diameter prop with low pitch and enough power to easily pull straight up and out of the hover.
3...over-sized rudder/elevator with some throw....more than low rates but 3d throw is not necessary for only hovering.
4...a long fuse (u-can-do) wouldn't hurt either.

once you do it for a while(years) you will be able to hover a washing-machine if it had 1.5/1 power to weight ratio :eek:

What amount of coupling to use between elevator and flaps.
 

Thank you very much. I'm new at this (can ya tell?) All the information on this site is great!!Thanks again......Craig F

What amount of coupling to use between elevator and flaps.
 

http://smilies.networkessence.net/s/...her/ignore.gif

Good one...LOLROTF http://smilies.crowd9.com/otn/laughing/yelrotflmao.gif

Greetings from Sunny Queensland.
 

Thanks Guys.

At present my flaps (ailerons), move 30 degrees when the elevators move 45 degrees.
If you guys can flat spin with the them mixed in then I must have too much coupling.

Uncoupled I can easily get a great flat spin. With coupling I can not get the model to spin at all.
The C.G. is (almost) at the point where no elevator is required for inverted or upright level (what's that?) flight.

Maybe I have too much coupling.?
Perhaps the C.G. should go back further?

I think I will try both.

What amount of coupling to use between elevator and flaps.
 

actually I believe the proper term is "MIXING" not "coupling"

as in....."I mix elevator to flaperon/spoileron on a programmable mix switch" (up elevator to down on both ailerons and down elevator to up both ailerons)

coupling would be ....I get "pitch coupling" in knife-edge flight (plane pitches toward belly or canopy) or "roll coupling"....plane rolls with rudder input!

anyway back to the question about leaving it on during flat spins.....
I have my "mix" adjusted for maximum (as far as the throw will go in both directions) If I leave it on during flat spins (up-right or inverted) I get a terrible mess....so I leave the switch off. It may work well if you only had a little mix on....unfortunately i only have 1 programmable mix switch on my radio :( and I need that mix for other maneuvers. If I had more switches I would experiment with other percentages.

Greetings from Sunny Queensland.
 

Thanks outssider:

As this forum is rated for general exhibition, I refuse to get into a discussion as to whether I pitch toward the belly or not during coupling .

But your point is valid and your input valued.

In future I will switch to mixing and leave the coupling for another place. :D

What amount of coupling to use between elevator and flaps.
 

Well, I know that a lot of pilots always give full rudder and full down or up elevator and only move the aileron sticks when trying to flat spin. You will sometimes have to back of the throttle, elevator and/or rudder in order to get a nice flat spin. Keep experimenting.

What amount of coupling to use between elevator and flaps.
 

texas...

did you ever notice (in general) that it seems to take much more up elevator to do a up-right flat spin than it does down elevator to do an inverted flat spin!!

the showflyer will easily do inverted climbing flat spins but upright flat spin looks like poo :p

What amount of coupling to use between elevator and flaps.
 

Greetings from Sunny Queensland

I also have noticed that Outssider.

Could this be an artifact of the dreaded coupling ?

I mean that with most fun fly models there is more fin and rudder area above the fuselage than below it.
This may be inducing an adverse roll. ;) :p

How this helps the inverted and not the upright spins I don't know. :spinnyeye

Greetings from Sunny Queensland
 

Texas.... Thanks for the details on how the climbing flat spin is done.

I have still not been able to achieve it. My fun fly models are of the tail boom variety. They are overpowered and the control surfaces are oversized with ridiculous amounts of throw.

I flew them today with the mixing reduced and the cg further back. They still refused to flat spin with the mix in. Yet they both flat spin very well without any mix.

I wonder if they need side area? Perhaps a profile fuselage would help?

Has anyone done the climbing flat spin with a model utilizing a tail boom? (The only side area being the fin and rudder.)

If so, what mixing do you use if any between the elevators and ailerons (flaps)?

What amount of coupling to use between elevator and flaps.
 

Graeme....


I can't get any flat spins either with the mix on.....must be off.

the phenomenon with needing more elevator throw for upright flat spin is also very noticeable in my 540 edge. upright requires full 3d rate while inverted can be done on lower rates (for elevator).

What amount of coupling to use between elevator and flaps.
 

The showflyer does even climbing invereted flat spins, but upright it looks pretty nasty. You are right outsider.
I will take the engine out of my showflyer (need for different project), so it will end up for grabs soon. Interested anybody ? Drop me an email or PM.