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Has anyone installed a Rotax 912 in a 0nex. What prop? Motor mount? CG location? I have access to a used 912 and considering hanging on my 0nex. Any info from my fellow builders would be appreciated. Stay healthy....stay happy! Tom Ryan 0nex 74

I certainly plan to install a 912UL in a Onex, and I thought it would be hanging on the nose by now, but I got sidetracked with another project. I'll be making my own mount if I ever get back to work on it. The CG of the engine probably needs to be 3-4 inches farther forward than the CG of the Aerovee, but I haven't picked an exact distance to start with yet.

The prop is a problem with the stock gear. Even using slightly larger tires, you won't be able to run a normal 912 prop. I'm actually expecting to use a 4 blade Bolly prop. There is a place that can make taller gear, but there's a significant wait time. Of course in retrospect.

Rusty

tom0nex74 wrote:Has anyone installed a Rotax 912 in a 0nex. What prop? Motor mount? CG location? I have access to a used 912 and considering hanging on my 0nex. Any info from my fellow builders would be appreciated.

Tom,

I just hung paper on a Rotax-powered Onex a couple of weeks ago. The guy made his own engine mount, and used a Warp Drive three-blade prop. CG was pretty far forward but not out of the limit with a pilot onboard.

I don't know if he's flown it yet, but he was going to report back to me on cooling and handling. This type of installation is definitely in the "experimental" category. I'm interested to see how his experiment works out.

Personally, having flown the original Factory Onex prototypes with AeroVee engines, I would definitely opt to go AeroVee. MUCH simpler installation, no need to make your own cowling and motor mount. Much lighter airplane overall, and plenty of performance. But that's just me. I'm not one to make extra work for myself (or extra expense). As always, your mileage may vary.