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n85ae
12-12-2012, 05:23 PM
I know it is NOT rated for aerobatics, but I'm curious how many people
have actually spun their kitfoxes and what were the results of spinning
it? Please don't reply with the why you shouldn't spin it. I've been flying
mine for a long time and have almost spun it a few times from botched
stalls, etc. So it's always a possibility.

I'd like to know what the spin characteristics of the plane really are. What
effect do the flaperons, etc, have on the spin? How fast does it spin? Does it
spin the same to the right as to the left? I know it goes towards earth like
the SR-71 when pointed nose down so clearly speed build up is an issue.

I think it would be good to get this information out, because I know the plane
can spin, and that people do in fact spin them BUT the information is a bit
thin if you know what I mean.

Thanks,
Jeff

N85AE Series 5, IO-240B

sdemeyer
12-12-2012, 06:29 PM
I put my IV in intentional spins a few times, before I sold it. It rotates fast and comes down fast but recovers using the standard recovery techniques. I don't remember how many turns it took to recover but I am still alive. I do remember being surprised at the jolt I felt when the rotation stopped. Seemed to rotate a few moments after applying opposite rudder and then wham, immediately stopped rotation... It picked up speed very fast, immediately after recovery. I'm no aerobatic guru by any means so your mileage may vary....

Esser
12-12-2012, 06:36 PM
I don't have Kitfox spin advice but unless its prohibited I think you should spin every plane you fly. You want to know what you are dealing with if you ever do an unintentional spin which will probably be close to the ground. For example I remember flying an SZD-55 Puhacz glider and when that thing spun it lost 800' in the time it took to snap your fingers.

When me and Natalie go flying we always do a few spins on the way back to the airport.

So don't be shy to as the spin question. Spin away. I do know that there are videos of Jimmy Franklin spinning a IV on youtube.

BigJohn
12-12-2012, 08:28 PM
I have the series 5 with the larger elevator and VG's, You have to work at getting it into a spin and it comes out very easly, infact if you just give it a little time on it's own it will put it's self into a steep spiral, not saying all the fox's will do this but mine does.

szicree
12-12-2012, 09:48 PM
For example I remember flying an SZD-55 Puhacz glider and when that thing spun it lost 800' in the time it took to snap your fingers.

Probably just seemed that way. A bowling ball takes over 7 seconds to fall 800 feet.

DanB
12-13-2012, 03:27 AM
It is unfortunate that the FAA no longer requires students to go through spin training. When I got my ticket over 10 years ago, my instructor asked me if I wanted to do it anyway...I'm glad I said yes. He did ground training with me first and then we went up. I can still remember how that C172 broke to the left and the the plane going into a spiral straight toward Tera Firma. The g-forces build quick and it was quite an adrenaline rush.
If you have never spun a plane, I would highly suggest going through the training with an instructor that knows how, it would be worth every penny you spend.
FWIW

n85ae
12-13-2012, 09:56 AM
Actually I've been doing Emergency Maneuvers and Aerobatics training in a
Decathalon, and Super Decathalon, which led me to start wondering about
my Kitfox. It's a very nice handling plane, but I don't want to worry that if
I get it in a spin that it has some evil characteristics.

My forward pitchover (tailplane stall?) some time back with 22 degrees
flaperons led me to think seriously about getting some training outside of
just the normal stuff. The first time flying a plane when I was hanging
in the straps upside down was pretty unnerving until I got used to it.
Same thing with a spin unil you spin a plane, you always have some
lingering nervousness, especially when doing stalls.

As a side note my plane no longer has a trim assist spring, and I
mechanically blocked the 22 degree position. I think the extreme tail
incidence needed to trim for 22 degrees flaperons led to the tailplane
stall I had, BUT I can't prove it (other than to myself). In any case
without the spring and the 22 degrees the plane is very well behaved
and I've flown the heck out it trying to get it to act up but it doesn't.

Regards,
Jeff

jtpitkin06
12-13-2012, 05:03 PM
Here's a link to spin testing on the EuroFox. Nothing particularly scary. Spin entry is slow and has a nice nose down attitude. Near the end of the video the pilot does a 5 turn spin and it takes 10 seconds. There was no tendency for the spin rate to increase or the nose to rise and go flat.

Recovery is normal opposite rudder and elevator was placed near neutral to break the stall.

I really like the way the aircraft pops out of the spin with no tendency to reverse direction.

You can see the rudder pedals on the right side to see pilot inputs for spin entry and recovery. The low sun angle makes it easy to see the rotations.

It's a great training video for anyone about to do spin training.

http://www.youtube.com/watch?v=JifpxUFgJa4

John P.

Dave S
12-13-2012, 05:51 PM
Jeff,

I have to concur that the 22 degree flap position can introduce some interesting reactions from the aircraft, particularly with power on stalls. I have both the 11 and 22 degree positions as designed, however, seldom use the 22 degree position. Primary exception is short final in calm conditions....I'll use it then. The 22 degree position does not give very much additional reduction in stall speed compared to 11....and we land a KF pretty darn slow anyway.

One thing to consider in pondering how a particular Kitfox behaves in spins regards the fact that very few of our airplanes are built the same. At least theoretically, that means various Kitfox aircraft may very well behave differently in a spin because they are constructed differently. In particular, the weight and balance is different with different weight engines and construction modifications to account for the weight and position of the engine mounting and any counterbalance weight.

Two airplanes may have an identical weight and balance, however one which achieved the balance by having a heavy engine counterbalanced with a battery in the tail (so the weight is further from the CG) can have an impact on rotational dynamics and ease of spin recovery compared to a kitfox of the same weight with a lighter engine and the weight closer in to the CG.

In other words, a KF with a 582 or a 912 could not necessarily be compared to each other nor to a KF with a heavy engine such as a Lycoming up front and some weight in the tail.

Sincerely,

Dave S - Flying
KF7 Trigear
912ULS Warp Drive
St Paul, MN