Xenon Problem may delay Oshkosh arrival

[ventana7]

Well I encountered a BIG problem with the new Xenon turbo today and it's arrival at Oshkosh may be delayed.

The day started innocently enough - Scott was going to go up and do a bit of early morning flying before we packed up for Oshkosh.

He filled the 23 gallon tanks full for ballast, then took off. Well the new turbo cruises at about 3800 rpm easily solo and at that rate only burns about 3 gallons per hour. So that is over 7 hours of flying time.

Scott has been up for several hours now and refuses to come down!! And since he won't run out of gas for 4 or 5 more hours I have no idea when we will leave for Oshkosh.

Hopefully he'll have to pee soon and when he comes down I can grab the keys and hide them.

Anyway the new red turbo will be in the booth to show off and the black machine will be flying at Fond du Lac.

See ya all there.

Rob

[Timchick]

Maybe he's already half-way there. Doesn't sound like such a bad problem to have. Good luck at Oshkosh. And have some fun, too.

[GyroRon]

Rob, it is not good to run those Rotax engines at that low of a rpm.... Call your friends at Lockwood aviation and talk to Carey there.

[Brent_Brown]

How low is OK?

[GyroRon]

I have been told by several Rotax mechanics that the engine is designed and intended to be run in the 5000-5500 rpm range. That running in the high 4000 rpm range would be ... OK.... but that it was made to be run " hard " and that it is bad to " baby " it.

Just passing on what I was told by several so called experts.

[Doug Riley]

I imagine that prop pitch has much to do with this issue. Running it at 3800 with high pitch and lots of boost amounts to lugging it.

Just make sure it isn't over-propped.

[Heron]

Rob . . . some numbers available? (speeds, etcoetera)
thanks
Heron

[Rehan K.Janjua]

Hello Rob.

Glad all is well with the XENON.
Had to rush on this post to see whats the problem.

I wouldnt blame Scott for havin fun.

Happy and safe flying.
Rehan

[ventana7]

Ron,

Thanks for alerting us to a potential problem. It seems we are OK though.

Scott and I each happened to go to the Lockwood booth at different times today and asked about running at low rpms.

Scott spoke with Phil Lockwood and I spoke with another tech guy (Carey is not here) but we both got the same answer.

Phil said the only issue is if you burn 100LL and don't use TCP to scavenge the lead out it is good to run the engine around 5,000 rpm to burn out some of the lead.

If you use TCP you do not need to do that.

If you use TCP or use unleaded premium auto gas as we do then Phil said the lower rpm you can run your engine the longer it will last. So cruising at 3,800 to 4,400 is great for the engine.

This also bears out the actual real world results of the Italians and S.Americans who are using the 912 Turbo RST. They are running them at 3800-4800 and going way past TBO on them for that reason.

So that's the word from the experts.

Rob