SonexBuilders.net

Hi all, new to the forum. Not so much to experimental building. I recently started building a onex. Currently I fly an RV-7. Previously built a challenger, sonex and mosquito heli.

I'm looking for an equivalent of a folding wing RV-3. This for hanger space reasons and my mission. The onex seems to fit the bill except the for the power plant options. The revmaster seems like a decent option but I want and need more power. My aerovee/sonex was underpowered hence the reason I sold it. I know the onex is smaller, lighter and narrower but living near the mountains I like extra power.

So...why can't I put a jab 3300 on my onex? I don't need LSA compliance. Up here in Canada the rules are different and I'll register it as a Basic Ultralight. This means I can do whatever I want as long as it's in the Ultralight weight category.

The ulPower engine (107 hp) seem nice but expensive. For $12,000 or less I can find a used 3300 with 120 hp.

Questions:
1. Will the 3300 fit under the stock onex cowling?
2. Am I going to run into major CG issues?
3. Would the Sonex/Jab3300 engine mount fit?

Thanks for the help everyone

Darren.

1. Probably
2. Probably not. The Jab3300 is close to the Aerovee weight and lighter than the proposed Aerovee turbo.
3. Definitely not. the Onex has a vertical bulkhead. You will need to fabricate your own.

One builder put a Jab2200 in his Onex. He had to move the engine quite a bit forward for CG. This required a custom mount and cowl.
http://www.floridasonex.com/Featured.html

I too like the folding wings.
I might still build a Onex as my next project. Or a Panther. But the D-motor looks enticing. So do the UL power plants. As does the Aerovee Turbo. And I have experience with the Jab3300. It will not be a stock Aerovee, not enough power.

As for LSA compliance, as long as you maintain stall and gross limits to LSA, you can always placard the plane not to exceed X RPM continuous power like the Carbon Cubs do.

The Panther does look interesting, I agree, but they'll have to go thru the initial builder/beta testing and that may take a year or so. Then I think it'll fill a nice niche. Forgive my ignorance, what's a D motor??

That Jab 2200 onex doesn't look good to me. No offence to the builder but I ain't doing that. I'd rather go with the Revmaster. I wouldn't know how to custom fab an engine mount for the 3300 but like most things in experimental aviation, ask enough questions and the right person can be found.

Agree with you on the Panther. I don't want to be in the initial builder group. But I haven't ruled it out.

D motor is a Belgium engine trying to get a foothold in the USA.
http://www.dmotorusa.com

Another prospect is the Viking
http://www.vikingaircraftengines.com/onex.htm

Of course, always be thorough with your research before committing to any engine vendor.

fastj22 wrote:Another prospect is the Viking
http://www.vikingaircraftengines.com/onex.htm

I believe the Viking would be too heavy. Perhaps not. But do you really want to deal with Jan Eggenfellner? Not me, not ever. Sorry! But if you were going to put that much weight on the nose why not consider a 120 HP, 3.0 Corvair?

Great power, extremely smooth, will turn higher RPMs than a 3300 continually without overheating (temps are NOT a concern with this engine), parts are readily available, support is great and growing more so every day. You can build it yourself or buy it ready to fly for nearly 1/2 the cost of a 3300 Jabiru ($11,750) and it's handcrafted in the USA.

http://flycorvair.net/2014/02/02/comple ... -for-sale/

I'm certain you have all seen how the Panther performs on Corvair power:

http://flypanther.net/2013/05/17/flight ... b-woolley/
(scroll down and watch the video in full screen - at about the five minute mark the Panther and RVs start mixing it up)

And surely you've seen a Corvair perform on a Sonex before:

http://www.youtube.com/watch?v=9Uh5HTXtNLg

OK ... I seriously do think it would be too much weight on the nose of the OneX, but having flown the available Sonex engines I believe the Corvair is the best match for the Sonex air frame.

One man's opinion ...

Dale
N319WF
http://kitplanes2.com/blog/2013/12/ownerbuilder-2/

I second the comments on not wanting to go the "egg" route when choosing an engine. It's obviously very tough to break into the experimental world with a new power plant. Ulpower seems to be doing ok but way too expensive for most of our pocketbooks.

The corvair does look interesting but ya, too heavy I think and too much cowling modifications I'm afraid. I'm cool with "experimental" but some experimental is too much experimental for me:)

On barnstormer right now is a jab 3300 for $10,500. Pretty new. That's what I'm talking about !! Personally I'd prefer one with a few more hours on it. Say 200 hours or so. This way I'd feel better that the engine is out of the "infant mortality zone". But if the time were right I wouldn't hesitate to buy this.

A few thousand more than a VW, 6 cylinder smooth, swing bigger prop, WAY more power, WAY more fun:)
And isn't that what it's all about.

Darren

I too think the corvair will be too heavy, as well as the Viking. There was a Onex builder who was going the jab 3300 route, but I think I saw his project go up on barn stormer last year.
The best options will be to go with a turbo aerovee and get factory support.

I have compiled a long list of engine alternatives some months ago.

http://onex-svingenb.blogspot.com/2013/ ... tives.html

The easiest "upgrade" is definitely a Revmaster (same mount, slightly modified), but it is really an upgrade regarding HP? I have never seen a dyno test of either Aerovee or Revmaster. No way to tell. The Sauer 2400 UL I know produces considerably more HP than the Aerovee, it is almost like a 100 HP Rotax. There are lots of cool options :)

But you could also do something like this: :D
Sonex with a Rotax 912 UL with turbo and Fuel Injection/ignition from http://www.sdsefi.com/aircraft.html

The turbo aerovee is of course going to go thru it's teething pains and troubleshooting. Plus from what I understand the weight is going to be near or more than the jab 3300 (I need to double check this).

I don't really want to be the beta tester. The Sauer seem interesting but what about support and reliability?

To me the best value for power and weight is the 3300. Albeit a used one. I won't be buying a new one. I don't know why more onex builders haven't gone this route?? Am I missing something huge and obvious?? If so, please enlighten me:).