Nervous about Rotax

Jim Stewart wrote:
Jay Maynard wrote:
I spent a day and a half at Sebring looking at aircraft. As I expected,
there are only a few that fit what I'm looking for. Of those, only one
(the
AMD Zodiac XLi) uses a Continental engine. Everyone else (and, indeed,
nearly everyone else building an LSA period) uses Rotax 912s.

I'm not fond of the idea of flying behind a Rotax. I know there are
lots of
them out there (although I doubt what one guy told me, that there have
been
more flight hours on Rotax engines than there have been on Lycomings and
Continentals put together), and I know that lots of folks like them,
but I'm
not at all sure they're for me.

I live in Fairmont, Minnesota, a town of 11000 50 miles from anything.
I'd
like the local A&P to be able to do maintenance on the engine, and fix
it if
it breaks. I also need to feed it a steady diet of 100LL, as every
gallon of
automobile gas sold in Minnesota must have at least 10% ethanol (and
that's
supposed to go up to 20% in 2010).

You will have more frequent plug and oil changes.
The 912 really wants to drink premium mogas. Out
here on the west coast, we've been running 5-10%
ethanol without any problems. Can't speak to your
situation though.

On the plus side, plugs cost $3/each and it only
takes an hour to do plugs and oil.

I'm told the Rotax runs fast (red line on the Tecnam Sierra I sat in was
5500 RPM, and supposedly everyone recommends idling no lower than
2500), and
that it has very tight tolerances, and demands lots of special tools.
Yeah,
it's just different, not necessarily worse - but there's a difference
between that and an O-200, where if I find myself at some random field
with
a mechanic, I can be confident he can at least get it running.

The top RPM will be limited by your prop pitch.
My plane never exceeds about 5100 rpm in cruise.
I still get 1000 fpm climb on a cold day and I'm
happy with the pitch.

I should add that the 912 is available with three
different gear ratios and the Zodiac might be
different than the CT that I fly.

2000 RPM idle is fine. 2500 is good for warmup.


The Zodiac's seating looks weird, although I'm reserving judgment until I
get to actually sit in one (the one they had at the show was being
delivered
to a customer there today, so they didn't let anyone sit in it, and I
didn't
get to go take a demo flight in the one they had there for that purpose).
I'd still like other options, but unless I'm convinced that the Rotax
isn't
going to find itself at some point sitting in the hangar while the
engine is
shipped off to another state for repair (or, worse, waiting on a
replacement
cylinder that never comes because they're all being put on new engines),
there aren't any.

Can't speak to the Zodiac, but can talk all day
about the CTSW (:

Pluses for the Rotax are no thermal shock issues,
will allegedly run for 30 minutes at 50% power
with either oil or coolant gone, and 5 gallon/hr
cruise. The engine is also very smooth, especially
at an economical cruise setting. It starts very
easily. No mixture control. The engine just
behaves like a giant electric motor with a speed
control.

As for support, I've had no problems with my 912
so I don't have any direct experience. I know
that the west coast FlightDesign distributer has
worked closely with Rotax on some safety directive
issues and has gotten parts and support quickly.

"Jim Stewart" wrote in message
The 912 really wants to drink premium mogas. Out
here on the west coast, we've been running 5-10%
ethanol without any problems.

Hi Jim,
Glad to hear your good vibes with the CTsw. On the "running ethanol" issue,
I wrote two different "named" Rotax employees 2 years ago about increasing
the 5% ethanol content limit in their manual, and I sadly heard nothing from
either. I took that as confirmation of their continuing customer service
history. A bump to 10% would put them into new US mogas standards. Are you
blending 100LL to get the 5%?

Mike Isaksen wrote:
"Jim Stewart" wrote in message
The 912 really wants to drink premium mogas. Out
here on the west coast, we've been running 5-10%
ethanol without any problems.

Hi Jim,
Glad to hear your good vibes with the CTsw. On the "running ethanol" issue,
I wrote two different "named" Rotax employees 2 years ago about increasing
the 5% ethanol content limit in their manual, and I sadly heard nothing from
either. I took that as confirmation of their continuing customer service
history. A bump to 10% would put them into new US mogas standards. Are you
blending 100LL to get the 5%?

Here's a ctflyer.com thread you might find interesting:

http://www.ctflyer.com/viewtopic.php?t=1145

I've not blended 100LL. I might if I anticipated
a trip at 10,000 feet.

I believe Rotaxs can be serviced at Stanton Sport Aviation (KSYN).
Unleaded auto gasoline without ethanol is available in Minnesota at
some gas stations, marinas, and airports, although not at Stanton.

On 2008-01-21, xyzzy wrote:
The O-200 also runs best on mogas. They have serious lead fouling
problems.

erf.
Am I hosed, then?

The cylinders on those small bore continentals aren't exactly known
for their durability either.

Yeah, but you hear about O-200s routinely going well past TBO, to 2400 hours
at least (one guy claimed most fo the ones he knew about went to 3000 with
no problems, but I'm not sure how much I believe that). OTOH, the consensus
seems to be that Rotax 912s don't seem to want to make it past 800 or so,
never mind the 1500 rated TBO.

That said, I would probably prefer an 0-200 over a Rotax mainly for
the reason you cited -- the universality of its design, anyone can
work on it, etc Just don't think it'll need less work than a Rotax.

I'm not so sure about that...but, either way, I know I can get it fixed just
about anywhere, unlike the Rotax.
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
http://www.hercules-390.org (Yes, that's me!)
Buy Hercules stuff at http://www.cafepress.com/hercules-390

On 2008-01-21, xyzzy wrote:
On Jan 21, 10:45 am, Jay Maynard
wrote:
I'm not buying an average aircraft. I'm buying one for me. :-)
True, but you do have to consider resale value. Or maybe you don't?

I do, but I figure I'm not alone in not believing the Rotax hype.
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
http://www.hercules-390.org (Yes, that's me!)
Buy Hercules stuff at http://www.cafepress.com/hercules-390

"Jay Maynard" wrote

I do, but I figure I'm not alone in not believing the Rotax hype.

I know it isn't fair to compare the Rotax 2-cycles to the Rotax 4-cycles,
but I can't help but it affect me.

I had some miserable experiences with a Sea-Do Rotax, and even with a new
long block, had just as many problems, and that was with the second one
(especially) being taken care of, carefully.

I WILL NOT ever EVER put my but in the air with a Rotax providing the power.

Period.

Cessna needs to get Continental to put that O-200 on a diet, and get the
weight down to what a Rotax 912 installation weighs.

I know that the O-200 may need more service in the long run, but I feel much
better about the possibilities of it continuing to run, until I pull the
mixture.
--
Jim in NC

My hanger neigbor just sold his CTX because nobody in the general area
could work on the engine. It was sitting in his hanger for a couple
months with the cowling off with an engine problem that couldn't be
repaired. Not sure if it was parts or experience holding it up but he
wasn't happy the last time I talked to him (I didn't snoop too much
into the details).
Robert
KCGZ

On Sun, 20 Jan 2008 18:46:34 GMT, Jay Maynard
wrote:

I spent a day and a half at Sebring looking at aircraft. As I expected,
there are only a few that fit what I'm looking for. Of those, only one (the
AMD Zodiac XLi) uses a Continental engine. Everyone else (and, indeed,
nearly everyone else building an LSA period) uses Rotax 912s.

I'm not fond of the idea of flying behind a Rotax. I know there are lots of
them out there (although I doubt what one guy told me, that there have been
more flight hours on Rotax engines than there have been on Lycomings and
Continentals put together), and I know that lots of folks like them, but I'm
not at all sure they're for me.

I live in Fairmont, Minnesota, a town of 11000 50 miles from anything. I'd
like the local A&P to be able to do maintenance on the engine, and fix it if
it breaks. I also need to feed it a steady diet of 100LL, as every gallon of
automobile gas sold in Minnesota must have at least 10% ethanol (and that's
supposed to go up to 20% in 2010).

I'm told the Rotax runs fast (red line on the Tecnam Sierra I sat in was
5500 RPM, and supposedly everyone recommends idling no lower than 2500), and
that it has very tight tolerances, and demands lots of special tools. Yeah,
it's just different, not necessarily worse - but there's a difference
between that and an O-200, where if I find myself at some random field with
a mechanic, I can be confident he can at least get it running.

The Zodiac's seating looks weird, although I'm reserving judgment until I
get to actually sit in one (the one they had at the show was being delivered
to a customer there today, so they didn't let anyone sit in it, and I didn't
get to go take a demo flight in the one they had there for that purpose).
I'd still like other options, but unless I'm convinced that the Rotax isn't
going to find itself at some point sitting in the hangar while the engine is
shipped off to another state for repair (or, worse, waiting on a replacement
cylinder that never comes because they're all being put on new engines),
there aren't any.

Morgans,

I WILL NOT ever EVER put my but in the air with a Rotax providing the power.

Period.


Yeah, mass crankshaft recalls and mid-time overhauls are just great!

--
Thomas Borchert (EDDH)

On 2008-01-22, Thomas Borchert wrote:
Morgans,
I WILL NOT ever EVER put my but in the air with a Rotax providing the power.
Period.
Yeah, mass crankshaft recalls and mid-time overhauls are just great!

One theme I heard at Sebring was that Rotaxes never make it to TBO. OTOH,
I've also had people tell me they run forever. What's the difference? If
it's maintenance, how do I make sure mine gets the kind that lets it run
forever, instead of the kind that needs an overhaul at 800 hours?
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
http://www.hercules-390.org (Yes, that's me!)
Buy Hercules stuff at http://www.cafepress.com/hercules-390