The dreaded flat spin
 

Beware of the flat spin!!! Yikes, I put my sky scooter into the deck HARD after I couldn't pull out from a flat spin soon enough. It started from less than 100' up, so not much time to get it under control. Other times It went into a flat spin, I
would kill the motor and turn full opposite of the spin, then throttle back on and it usually came out of it pointing straight down but enough air to pull up and fly away. When she finally stopped spining I was only about 10' off the ground and
WHAMMM!!! Had to hike about 150 yds. I hate that 'walk of shame' back carring pieces. The nose with motor and gear box was about 15' away from the fuse. & wing. Wires torn loose, prop broken. The fuselage was broken half way through back at the receiver position. Double dirty darn!!! I hate when that happens!! Another thing I have noticed is that every time she has gone into a flat spin its been turning to the right, and the nose has been a bit high as in heading toward a stall. This usually happens when she is at a distance and the attitude of the plane is not so clear to keep the nose flat or slightly down. The question is, is there a standard procedure for recovering from a flat spin?
Rick

RE: The dreaded flat spin
 

You're probably just putting the plane into a simple spin, not a flat spin. A simple spin is where the plane spins around its CG with the nose pointed at a downward angle. Flat spins are where the plane is spinning around its CG, with the nose level.

Most planes will recover from spins if you just let go of the sticks and wait it out. Forcing a recovery requires rudder control, which you don't have. Ailerons are useless because the wing is stalled. Elevator is what put you into the spin in the first place, and more won't get you out of one. Spins can occasionally be fatal for the plane.

The real solution is to not get into a spin in the first place... I don't know why, but most people panic and yank full up elevator when their plane gets out of sorts. This is the WORST thing you can do, and usually the end result is the plane stalling and going into a spin.

RE: The dreaded flat spin
 

Matt,
Thanks for the response. The spin I got it into was the flat type with the nose just barely pointing down and the plane spinning around its CoG almost like wings were the blades of a gyrocopter. It wasn't really falling that fast and probably would have done less damage if I had just let her go in like that. You just hate to see em fall.
Rick

RE: The dreaded flat spin
 

Wow. I wouldn't have believe that a Sky Scooter could get into a flat spin, especially if you weren't trying. Or were you? ;)

Like I (think I) said, probably tail heavy. It should balance at 4.5" back from the leading edge of the wing at the fuselage. If it was nose heavy, the nose would drop and it would come out of the spin.

RE: The dreaded flat spin
 

Flat spins are a lot of FUN, I have a DP Edge 540 with a ZDZ 50 and it flat spins well. They look awesome with smoke on. To recover with power, apply opposite rudder and full throttle to power out. Without power (I know because I have deadsticked in flatspins before) you need full down elevator and opposite rudder to get the nose down and gain airspeed, if you don't the plane will continue to spin until it meets the ground.

RE: The dreaded flat spin
 

Dreaded?

RE: The dreaded flat spin
 

Mikerjf,
I can't say that the dozen or so times she was put into a flat spin, that it was done on purpose. Nor can I say that each time she pulled out, that it was from anything I deliberately did. Each time it spun out, it became less threatening as the recoveries were repeated. The sequence 'let go of the stick. Throttle off, throttle on', seemed to work in several spins. Didn't work this time. The sky scooter has no rudder. Ailerons, elevator & throttle. I think a rudder would be helpful. Soooooo, Until I figure out a reliable sequence or procedure, I'm afraid they'll be a bit dreaded. The learning curve/challenge is half the fun. Thanks all, for the insight and comments.
Rick

RE: The dreaded flat spin
 

Without a rudder, what you're doing is the best thing you can do to attempt a recovery. Hitec/Multiplex is coming out with an updated, more advanced version of the Scooter called the Space Scooter. It'll have a semi-symmetrical airfoil and a rudder, if what I saw at Toledo is any indication.

Every time this thread gets updated, I just boggle at the prospect of a flat-spinning Sky Scooter :)

If you dread them, don't put yourself into a situation where you get into them. Check your balance.

RE: The dreaded flat spin
 

Just bustin'. I get a kick out of flat spins, but on something without a rudder I don't think I'd look forward to them either. Standard spin recovery is PARE, Power off, Ailerons neutral (opposite aileron puts the stalled wing in deeper), Rudder opposite rotation until it stops rotating (wind up with both wings stalled), Elevator down after rotation stops to unstall the wings and get flying speed. Without a rudder your pretty much on your own. It could be prone to flat spins because the cg's back too far, try moving it up some. Or if you get the recovery figured out and down pat, move it back a little, that should put it in deeper, be a lot more fun (if you can get it out). One of the guys I know got a Duraplane flat once, didn't know what to do and wound up plopping it in flat. He won't spin anything anymore, but I thought it was pretty cool, actually didn't bust anything. Good luck.

Have Fun!

Mke

RE: The dreaded flat spin
 

Matt,
I've been checking out the ads on the space scooter. I've also been talking to Mike at Hi Tech about it, (he says they are currently flying and testing it). In the ads, it mentions two servos, and Mike @ H.T. assured me that it will have ailerons. I have to assume that it will be without a rudder. The thinner, semi symmetrical wing is is being advertised as being interchangable with the sky scooter fuse. I'm looking to pick one up as soon as they are avaliable. I will check my CoG on my scooter. I have two dots I placed under the wing at 4.5" from the leading edge root. It has always balanced out fine, but, I was using a new batt-pack with a square configuration instead of the OEM flat pack. So I may need to slide it as far forward as possible to at least give it chance to recover. Here are a couple of links about the space scooter. What's in the ads, and what I'm being told by Hi Tech are a little conflicting.
http://www.modelspot.com/mpx/scooter.htm
www.multiplexusa.com
Rick

RE: The dreaded flat spin
 

I have a [link=http://www.rcuniverse.com/forum/upfiles/76492/Zx70134.jpg]Sky Scooter with a rudder[/link], and it will often enter a spin when giving full aileron in a nose high attitude... It's not a flat spin, because it's always ends up nose down at about 45 degrees when it starts spinning. The guys at the field call it a 'flat spin' though :)
The CG is a bit aft of stock because of the extra servo behind the wing. I have never had to use the rudder to recover. Normally, I just let go of the sticks and kill the power and it straightens out within one spin. If the power isn't killed, it just keeps spinning. I've done it intentionally a few times from high altitude. Wait until about 50 foot above the deck and then chop the power and pray :D
The Space Scooter sounds cool. I hope that someplace will just sell the wing by itself. The Sky Scooter wing is good for a trainer, but it doesn't fly inverted worth a darn.

RE: The dreaded flat spin
 

Kamikazi,
I talked with Mike at Hi-tech, (which will distribute the space scooter), and he confirmed that the wing from the space scooter will fit on the sky scooter. YEA!! All he would say about the space scooter avaliability is that pre-production units are being sent to Hi-Tech, and should be avaliable to us soon. I saw your pics of the scooter with the rudder. Nice job!
Rick

RE: The dreaded flat spin
 

Actually some airplanes do require aileron's to recover from a spin. I fly a T-45 (it's a jet though) that requires ailerons into the spin and rudder opposite. Inverted it requires ailerons AND rudder opposite the spin. You would think that with these prop driven airplanes that if anything, full power would force airflow over the elevator and allow some control (push the nose down to get more airflow over the wing or even give airflow over the inboard section of the ailerons that would allow you to roll out of it). Never flat spinned an airplane though, so I'm just guessing.

RE: The dreaded flat spin
 

Generally, in a spin or in any other stalled condition, aileron has the opposite effect if any. A stall is cause by going past the critical angle of attack. If you are stalled and apply aileron to counteract, the aileron increases the angle of attack, and therefore has the opposite effect. Rudder in the opposite direction of the spin will yaw the plane in the opposite direction, therefore increasing the speed of that wing, and hopefuly unstalling it.