Flat Spins Are Not Flat
 

I have a SebArt Suhkoi 50 electric. My flat spins are all nose down inverted or upright. I have moved the CG back past The recommended point and still nose down. Inverted flight is almost perfect, just a hint of down elevator needed. Should I continue to slide the CG back? Any ideas are welcome.

RE: Flat Spins Are Not Flat
 

CG is the best place to start. Go as far back as you dare. The only real penalty in having a really rearward CG is you must realize the plane will NOT fly on the wing normally without hunting in pitch and you commit yourself to always doing harrier landings. If you are comfortable with that idea, then you can move the CG back crazy amounts (which will make hovering, harriers and spins easier) but normal flying nearly impossible. However, with enough expo and control on the elevator (like 50 degrees and 50% expo) it is possible to manage the plane with a crazy rearward CG.

Another hint is to play with some flapperon or spoileron mix (either on a switch or mixed with the elevator). I've had planes that wouldn't KE spin without spoilerons but I think flat spins may require positive camber (flapperons) but not a whole lot like maybe 1/2" or so. Try and see.

In general, profiles are more difficult to spin nicely because the real good ones have a lot of frontal side area which fights the spin. The best flat spinning planes I've ever flown had very little side areas, and higher aspect wings. They also had less aileron throw so it was easy to simply jam the sticks in the corners, and then reverse the ailerons once the spin ensued to flatten it out. 3D planes have so much aileron throw it requires a gentle touch to get the amount of aileron just right wihout popping out of the spin before the nose starts to come up and it starts to get flat.

RE: Flat Spins Are Not Flat
 

Just one thing to add to WJ's ideas. You really need, at a minimum, 45 degs of elevator travel. 50 to 55 degs would be even better although some designs don't allow that much. If you have enough elevator travel and the CG is far enough aft you can actually get the plane to climb in a flat spin.

RE: Flat Spins Are Not Flat
 

yes,lots of elevator travel and enough power to blast the tail

RE: Flat Spins Are Not Flat
 

i agree, sometimes a airplane will need more throttle than others. Full elevator deflection def. will help.

RE: Flat Spins Are Not Flat
 

Do you think this will work? :D

RE: Flat Spins Are Not Flat
 

I love climbing flat spins....was doing them yesterday as a matter of fact with my Primo. Inverted climbing spins are even better!
I was doing them right down within a couple feet of the ground and then climbing right back up-in a flat spin the whole time of course!;)

RE: Flat Spins Are Not Flat
 

trublu, that otta bout getRdone.

FG, way cool to impress the crowd that way.

RE: Flat Spins Are Not Flat
 

naww, its gotta be tilted forward a bit ;)

RE: Flat Spins Are Not Flat
 

I pulled that pic from Extreme Flight's website. It is their Extra 300EXP. I didn't believe it could really get that kind of throw till I got mine. It is unreal. I have never had a plane that coud flat spin and do elevators like this little plane will.

RE: Flat Spins Are Not Flat
 

I'd like to try one of these for sure!