RV-9 with Rotax 915

I'm no A&P, but it looks like the camshaft is on the bottom, and the crankshaft drives the reduction gearbox/overload clutch.
 
The Rotax is better in nearly every parameter over an O-320. Designed from scratch to burn Av gas, rather then just compatible with avgas. Water cooled cylinders, 5000 RPM cruise with prop driven off cam (which turns half speed) instead of the crank. If memory serves the prop is clutch based alleviating prop strike inspections.

Also has a FEDEC and lower fuel burn. It would make the RV-9A an amazing plane, assuming CG issue is workable.

https://www.rotax-owner.com/en/component/jomclassifieds/advert/99-prop-strike-inspection?Itemid=495

Still not cheap after prop strike even with the slipper clutch … about $1000-1500 for a prop strike inspection but chances are that’s all you will need to shell out.
 
Yea I really like what Rotax has been doing. You can run ethanol car gas, newer model ones have proven stellar reliability, super light weight and compact. I would skip the carbureted models as they are finiky but the iS and newer are real gems.

Seems to me Cessna would have done much better with the SkySnatcher (OK SkyCatcher) if they would have stayed with the Rotax 912S. As it turned out with the O-200D they had less than 500 lbs. of payload in an aircraft designed for the training market.

Of course a lot of training is done in overloaded Cessna 150's but we don't wanna talk about that ...
 
Seems to me Cessna would have done much better with the SkySnatcher (OK SkyCatcher) if they would have stayed with the Rotax 912S. As it turned out with the O-200D they had less than 500 lbs. of payload in an aircraft designed for the training market.

Of course a lot of training is done in overloaded Cessna 150's but we don't wanna talk about that ...
I find it interesting that Vashon repeated that mistake with the Ranger.
 
I find it interesting that Vashon repeated that mistake with the Ranger.

Don’t forget the owner of Vashon marketing that it has a “real aircraft engine in it.”

I’m kind of a Rotax fanboy and am so grateful they’re making modern engines for aviation. The 915 is 145HP on a dyno at 45” and 5800 and the 916 is a 915 with an ECU remap putting out 165HP at 50” with 145HP max continuous vs 135HP of the 915. The 916 is coming soon.

There are some insane aircraft out there utilizing the 915. Y’all ever seen numbers like this? 36 MPG at 215 MPH.
 

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Don’t forget the owner of Vashon marketing that it has a “real aircraft engine in it.”

I’m kind of a Rotax fanboy and am so grateful they’re making modern engines for aviation. The 915 is 145HP on a dyno at 45” and 5800 and the 916 is a 915 with an ECU remap putting out 165HP at 50” with 145HP max continuous vs 135HP of the 915. The 916 is coming soon.

There are some insane aircraft out there utilizing the 915. Y’all ever seen numbers like this? 36 MPG at 215 MPH.
What plane is this?
Impressive numbers.
 
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Yes, but when will vans come out with a 2-seat 150ish kt kit plane, possibly offered in both tailwheel and nosewheel versions?
 
Yes, but when will vans come out with a 2-seat 150ish kt kit plane, possibly offered in both tailwheel and nosewheel versions?

I’m guessing you’re being facetious since the RV-9/9A is that plane.
 
I’m guessing you’re being facetious since the RV-9/9A is that plane.

Yes.

Also the 4, 6, 7, 8, 12, 14... :p

I thought it funny that the thread started by highlighting Vans' refusal to try new things, and other than the RV10, to this innocent bystander, that may as well be their company motto and claim to fame.
 
Yes.

Also the 4, 6, 7, 8, 12, 14... :p

I thought it funny that the thread started by highlighting Vans' refusal to try new things, and other than the RV10, to this innocent bystander, that may as well be their company motto and claim to fame.

ha you got that right—with roughly a third of all flying US E-ABs, Van’s is crying all the way to the bank.
 
ha you got that right—with [RVs] roughly a third of all flying US E-ABs....
What's your source for that statistic?

As far as Van being reluctant to sanction alternative engines, the data pretty much backs him up. About 5.6% of accidents happening to Lycoming O-320-powered homebuilts are due to mechanical issues with the engine, vs. 25% of Subaru-engine-powered homebuilts. Hondas come out roughly the same as the Subarus, except the sample size is pretty small.

The Rotax 912, on the other hand, comes out pretty good. It actually has the lowest rate of mechanical failure of all the engines I looked at.

Ron Wanttaja
 
What's your source for that statistic?

As far as Van being reluctant to sanction alternative engines, the data pretty much backs him up. About 5.6% of accidents happening to Lycoming O-320-powered homebuilts are due to mechanical issues with the engine, vs. 25% of Subaru-engine-powered homebuilts. Hondas come out roughly the same as the Subarus, except the sample size is pretty small.

The Rotax 912, on the other hand, comes out pretty good. It actually has the lowest rate of mechanical failure of all the engines I looked at.

Ron Wanttaja

Over 11,000 RVs have flown (according to Van’s who gets first flight reports direct from builders) — granted that’s world wide and not all are still flying, so I’m taking some liberty there. IIRC, there’s just over 30,000 E-AB US Registered aircraft, but I could be wrong. The percentage might be off, but no matter how you slice it RVs make up a sizable slice of the fleet, but I won’t quibble over the exact percentage,
 
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As soon as I posted, I knew there would be someone on PoA that couldn’t help themselves.

Adam, Across the Internet when pedantic class is in session, students are sent here for lab work.
I should just stop trying to use any form of humor, especially the dry variety, anywhere. It rarely goes the way I'd planned. Imagine me saying those exact words, but the same way a friend said them when asked if he'd performed a particular maneuver in a particular airplane... details omitted to protect the "innocent until reported to the FAA".
 
… Van’s….
The Rotax 912

I’ll tell you right now I’m trying to decide between building the RV-10 and the Sling TSi. Where I get stumped is pros/cons of running a 260hp motor at reduced power settings vs running a 145hp motor at full power.

I’m not worried about fuel flow, I’m wondering the practical impacts on reliability and simplicity/complexity.
 
I’ll tell you right now I’m trying to decide between building the RV-10 and the Sling TSi. Where I get stumped is pros/cons of running a 260hp motor at reduced power settings vs running a 145hp motor at full power.

I’m not worried about fuel flow, I’m wondering the practical impacts on reliability and simplicity/complexity.
Biggest con of the 145hp motor is that no matter how far you push the throttle forward, you can't get 260hp from it.
 
I’ll tell you right now I’m trying to decide between building the RV-10 and the Sling TSi. Where I get stumped is pros/cons of running a 260hp motor at reduced power settings vs running a 145hp motor at full power.

I’m not worried about fuel flow, I’m wondering the practical impacts on reliability and simplicity/complexity.

Most of everyone I know with a 10, myself included, run their 540s WOT with an average RPM of somewhere in the neighborhood of 2300 with no significant reliability issues. The 540 is really a pretty bullet proof motor. The Sling is a nice aircraft, but IMO it’s kinda like comparing a 172 to a 182, not exactly apples to apples.
 
…The Sling is a nice aircraft, but IMO it’s kinda like comparing a 172 to a 182, not exactly apples to apples.
I was just perusing the other thread again and know how you feel re: orange/tangerine. Reality is it will take a lot to convince me the TSi is the way to go.
 
Are Sling planes kit only?

I thought they were available factory finished, or as a kit.

iIRC at least some of their models can be purchased as flying aircraft straight from the factory, but their US marketing focus has been to the E-AB community.
 
To get a bit off topic,how do you think the 915 would do on an RV 3 or 4? According to previous posts, the 915 would need to be mounted farther forward. Essentially, the engine is a bit too light (915 is 185 lbs., 0-235 is 246 lbs.). Would it be too light on the 3 or 4? And even though the Rotax has less power than the standard 0-320’s at lower altitudes, the lighter weight would presumably compensate for that during takeoff & climb.
 
I’ll tell you right now I’m trying to decide between building the RV-10 and the Sling TSi. [...]

Another thing to consider is how long it takes to put them together. The Sling is MUCH faster to build.
 
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I'm not saying this is a prototype 915 rv9 from a few years ago, but I'm not saying that it isn't either
I wonder if there would be some way to incorporate a small baggage compartment in that extended space. I know it wouldn't be terribly usable with the engine mount going through it, but at least from what I can see it might be a good place to store a couple quarts of oil and some rags.
 
I wonder if there would be some way to incorporate a small baggage compartment in that extended space. I know it wouldn't be terribly usable with the engine mount going through it, but at least from what I can see it might be a good place to store a couple quarts of oil and some rags.
Or an air conditioner! There'd be plenty of weight allowance.
 
REALLY wish Van's would make something like an RV-9A with a turbo Rotax. This engine should be freed from the bondages of LSA aircraft limitations. Even if the firewall was extended a few inches farther adding cabin space would be great, or ballast up front as required.
 
REALLY wish Van's would make something like an RV-9A with a turbo Rotax. This engine should be freed from the bondages of LSA aircraft limitations. Even if the firewall was extended a few inches farther adding cabin space would be great, or ballast up front as required.

Not completely outside the realm of possibility, but there’d have to be serious market demand for them to go down that path. When the RV-10 was originally developed, there was the provision for 2 engine options: the Lycoming IO-540 and the Continental IO-360. They went as far to build and fly the second prototype with the 360. Nobody wanted it so they never offered it as a kit option.

Of course everyone has the option to roll their own solution. Maybe there’s an aftermarket opportunity for some enterprising individual to develop and market such a FWF package outside of Van’s.
 
For those that have been watching N179RV, the RV-9 with the 915 registered to Vans Aircraft, it looks like it’s almost arrived at OSH!

I hope they’re announcing a FWF package!
 

Lockwood thinks 200 knots true is possible at the engine’s critical altitude.

Interesting statement considering Van's has recently stated the VNE is 210 MPH true, not indicated as was sometimes listed before.

EDIT: Looks like the article has changed the above quote to "Lockwood thinks 187 knots true is possible at the engine’s critical altitude."
 
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This all sounds very promising. I've always felt the RV-9 hadn't quite reached its full potential. Sounds like we're headed for an 18,000 foot cruiser with a tiny turbo engine.
 
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