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I've been working up higher numbers of turns in spins in my straight-tail Sonex. I'm up to 5-1/2. Once it gets to about 4 that seems to be the max turn rate. Loss of altitude was about 1,500', with average G's about 2.7. Standard spin recovery works easily and quickly: power is already retarded, so center the stick, opposite rudder (does not even need full opposite; just a slight push past center), then recover to level flight. Fun stuff! I keep watching the video 'cause it's kind of mesmerizing even to me.
https://www.youtube.com/watch?v=gPzQ3Ruq8LY
This is an AeroVee so it spins much better to the left. It really struggles to spin to the right; it just doesn't want to do it. It's slow, flat and wobbly.

Wow, cool video! Gives me a lot of confidence in the stability of the airframe.

It's a little hard to tell, but were you holding aileron into the direction of the spin? I wonder if it would spin faster if you kept the controls crossed (left rudder right aileron), putting the left wing into a deeper stall.

Rynoth wrote:Wow, cool video! Gives me a lot of confidence in the stability of the airframe.

It's a little hard to tell, but were you holding aileron into the direction of the spin? I wonder if it would spin faster if you kept the controls crossed (left rudder right aileron), putting the left wing into a deeper stall.

No, just holding the stick straight back in my lap. If you relax the back pressure at all it starts to come out of the spin, so you have to hold it all the way back to keep it spinning.

Mike and others,

The record for the number of spin turns in a Sonex was once held by Marty Smiltneek (sp?) in Sonex No. 173. If I remember correctly, he did something on the order of 13 turns starting at or above 10,000 feet and ending at 1,500 feet. I haven't read that anyone else has beat Marty's adventure to this date.

Incidently, although the FAA aircraft registration website is down, the Sonex LLC website shows Sonex No. 173 to be currently owned by LeRoy Brandt, known to us for other reasons more recently; however, that information would appear to be out of date.

Art,,,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,Jabiru 3300 #261

I’ve done 2.5 turns in a waiex. Not sure I have the stones to go more, but the head swirls!

My experience with spins in the Sonex seems different from some others. The intentional spins that I have done were not more than 3 turns with typical results including easy, rapid spin recovery. However, a friend wanted to finish his PPL lessons in his Sonex (I had already completed the full flight test program in his Sonex) but his instructor wanted some familiarization time in the plane before he started instructing in it. At an altitude of about 2500' he began slow flight with a very shallow left turn, then back to the right with increasing bank angle. At the time I warned him that it was about to break, it did. He immediately put in left rudder and full left aileron and the spin quicly tightened, then he moved the stick to full right. After about five to six turns (I wasn't counting), I asked if he was doing this on purpose. He replied, "No, and I can't stop it." I took control and tried to recover but the stick was jammed all the way to the right and the spin was alarmingly rapid. I knew we didn't have much time and I had to try something fast so I neutralized the rudder, then jammed full left rudder and jerked the stick hard to the left. It centered and the rotation stopped. I began to pull back as much as I could, trying not to induce a secondary stall. Just as the nose started coming up, I had to ease left to avoid a tree.

For clarification, this instructor was a retired Army helicopter and fixed wing pilot and an active instructor with thousands of hours. I suspect he had been instructing in his C172 for many years but had probably not done any spins in a long time. Also, I deduced that since he is a big guy he was following the stick with his legs, then froze with his leg holding the stick to the right.

I'm not sure about the discrepency in the altitudes lost by others and I'm skeptical about the 8500' loss for only 13 revolutions. That seems like an extraordinarily slow spin. Our altitude loss was about 2400' with about 10 or 12 revolutions. Again, I stress that I wasn't counting so my estimate may be off but I was calm throuhout all of this and I guarantee that it was absolutely no less than 9 or 10 turns.

I've resolved, when letting others get familarization time, to not do slow flight at less than 4,000'.

Curious - did he ever explain why he used full left aileron?

No. I never asked. I think he just forgot the proper technique or was confused.

We are lucky to have you with us. Don’t Panic is an excellent motto.

Thanks for sharing your story.

Gordon

I start all my aerobatic maneuvers, including spins, at 5,000' (my personal minimum). My 5-turns lost 1,500' of altitude. I started at 5K and finished at 3.5K. By unscientific extrapolation 10 turns would lose 3K of of altitude.

https://www.boldmethod.com/learn-to-fly ... each-step/
"If you try to raise the low wing using aileron, it will stall even more, tightening the spin."

At normal aerobatic weights I find the Sonex to be very benign in a spin. Nothing crazy, but fast enough to get your heart rate up. And it will come out of a spin quickly with standard PARE recovery techniques. Spins were some of the first unusual attitudes I tested during my 40 hours. Even if you don't want to do intentional aerobatics in a Sonex (or anything else), getting some spin training and then doing some in your Sonex will give you a really good feeling for how to stay away from them, and give you the confidence that you can get out of them.