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killerfish72 wrote:Curious if there's any new updates on the OWW? Have oil temps been sorted? Any updates on performance in climb/cruise?

Still working on incremental improvements in cooling configuration. Progress is being made but a combination of weather, schedule conflicts, and other responsibilities have infringed on the test schedule. Hope to get more flying in this week.

I was just about to ask, so good timing. I'm still very interested in the RPM you see on climb, and level cruise. It it works well, I might need one of those props, but I'm skeptical from the size.
Rusty (Onex 912UL out of phase 1 finally)

13brv3 wrote:I was just about to ask, so good timing. I'm still very interested in the RPM you see on climb, and level cruise. It it works well, I might need one of those props, but I'm skeptical from the size.
Rusty (Onex 912UL out of phase 1 finally)

Rusty,

I am seeing RPM right at 5400 on climb (at 1400-1500 fpm!). I have not done a full throttle speed run in level flight yet, but will do that on an upcoming flight. I've been cruising the engine at 5000 rpm while we fine tune the cooling. TAS is around 145 mph at 3500 msl at that power setting.

Just flew it again this afternoon. More progress!!

Sonerai13 wrote:I am seeing RPM right at 5400 on climb (at 1400-1500 fpm!). I have not done a full throttle speed run in level flight yet, but will do that on an upcoming flight. I've been cruising the engine at 5000 rpm while we fine tune the cooling. TAS is around 145 mph at 3500 msl at that power setting.

Just flew it again this afternoon. More progress!!

Definitely promising numbers for this stage of the game. I'm betting you're going to find that it's under-propped a bit, and I'm certainly not surprised at the climb numbers. There's a rule of thumb that's generally accepted by the Rotax folks for fixed pitch props. They recommend setting pitch (if you can) to get 5650 RPM full throttle at your average cruising altitude. With 5400 on climb, I'm betting you'll blow right past the 5800 RPM redline with full throttle in level flight. Can't wait to hear more.

Cheers,
Rusty

Any Rotax updates? I'm sure it's practically summer in WI now :-)

I'd really love to try one of those Sensenich props, but without absolute proof that it would improved my performance, I couldn't justify the nearly $2100 price with shipping. Pity they don't have a try before you buy option.