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Just bought a Onex and flew it 2 hours home in really bumpy air. A couple of surprises. I built a Sonex some years back and thought the Onex would fly pretty much the same. Not so much! The ailerons are VERY effective and I was happy to have had the 2 hours in rough air to make friends. Pretty pitch sensitive as well. I don't remember the Sonex being that twitchy. But overall, once I had some time, and the air smoothed out, it was fine, just don't be ham handed.
My takeoff was pretty hairy because, again unlike any of the taildraggers I've flown, it was a bugger to keep straight long enough to get airborne, and the landing was the worst I've ever done, for the same reason. I was beating myself up thinking I'd better get more training ASAP if I was ever to fly this thing..... until I checked out the tailwheel setup. The owner had switched to a full swiveling setup with the attendant springs and chains. I thought that was a fine idea when I was checking the plane out, since I had wanted to so the same on my Sonex. Also had that setup on the Zodiac and Thatcher I had built...worked great.
However, I noticed that one chain was quite loose and the other was taut. Not good for ground handling. I shortened up the loose chain so the tensions were even and puttered around on the ground to check it out. Much better! We'll see what happens when I fly it again. I have the parts, so I may well put it back the the direct steering per plans.

Hey Ace,

I have built both a Sonex and a Onex. Like you, I expected them to fly the same. Not so much. The Onex redefines neutral stability.

Next time you are up, get the elevator trimmed as best you can for level flight. Then, slide your free hand forward and aft along the length of your thigh and watch the pitch change.

Enjoy,

Wes

Hmmm, I have the short tips, same engine. Same prop I think. I haven't checked the pitch.
Gonna take some high speed taxi runs and crow hops before I fly her again. Flying is easy, landings gotta be right, or they're hard
What are your cruise speeds like?

Ace,

My cruise is between 120 and 130 mph, depending on how hard I push it. WOT is 3600 RPM at 140 mph.

I am somewhat disappointed with the speeds but, I could be the poster child for out of rig. I didn't pay enough attention while installing the long tips and am currently flying with a big wedge and a dragging flap on the left wing to get level flight. I know I'm making good power because climb is 1000 fpm at 100 mph and 3400 RPM. So, I'm assuming that once I get around to drilling the right tip off and re-flexing it the speeds will improve.

I would be interested in hearing what your speeds are once you get comfortable with the plane.

Wes

Congrats on the Onex. I've never flown a Sonex, so no comparison. The Onex is a pretty neat plane, and the folding wings can be really handy for times when you need more space in the hangar. The Onex is just sort of a budget priced RV-3.

My prop is a Prince Ptip 54/48. Speeds on the way home varied between 100 and 140 mph rpms up to 3200, thanks the turbulence. Once I get sometime in smoother air, I'll get some numbers

I have a hard time getting past 100mph cruise with my 80hp AeroVee

I'm putting in a Wideband O2 sensor to help with mixture as I think I'm not getting full power.

Other problem I have is that it's tri-gear. The front wheel fairing makes the front wheel bounce in flight since it's providing lift. Gotta figure out how to secure the fairing in a better angle of attack

VillaAir wrote:Other problem I have is that it's tri-gear. The front wheel fairing makes the front wheel bounce in flight since it's providing lift. Gotta figure out how to secure the fairing in a better angle of atta

I think it's more likely the tire is out of balance and is spinning because of aerodynamic drag. Try some kind of light friction brake on the wheel before adjusting the pant.

If you have to refit your nose wheel pant, make sure it is mounted as far back as possible. I actually reshaped the front of my front wheel pant to almost hug the front of the tire. Many people mount it too far forward and too high and it catches the slip stream and causes yaw issues and the issues you are facing. Also make sure the nose wheel pant is angle slightly down in the front so the rear does not catch air from your direction of flight. Another trick is to fiberglass in a plate inside of the wheel pant just behind where the tire is to prevent air from cupping inside the back of the wheel pant causing excess drag.

Good luck!

Jake