Rotax announce new 135 HP engine 915S / 915iS

Celtico, as I understand it the V6 Rotax was dynamometer tested successfully but then failed several times in taxi testing. It was apparently flown either once around the pattern or never depending on who you talk to. All second hand or third hand info by the time I heard it, but I’m led to understand its correct. Believe what you want

Silvaire wrote:

Obviously if you really wanted to overhaul a 912 you might end up replacing almost the whole thing

Last time I wanted to overhaul a Lycoming I ended up replacing almost the whole thing as well. And it doesn’t have one piece conrods.

Last time I wanted to overhaul a Lycoming I ended up replacing almost the whole thing as well

What happened to that engine?

There are various scenarios:

• been in a bad accident
• had a severe prop strike / prop blade came off during taxi/flight
• not been run for months or even years and is thoroughly corroded as a result
• been overhauled a number of times (crankcases are scrap due to multiple boring, though the main internals should be fine)
• been badly assembled and shagged itself

tomjnx wrote:

Obviously if you really wanted to overhaul a 912 you might end up replacing almost the whole thing

Most 912’s are not certified. The guaranty is 1 year? When the guaranty has ended you are on your own in any case, and can do whatever you want. There are lots of third party parts for 912s; turbo kits, “big bore” kits, EFI kits etc. Only for a certified engine is there a need for an eventual factory replacement of core casing with crankshaft, which is just as good in my opinion.

And the last time we had an o-200 it was the same. Crankcase cracked, crank out of limits, camshaft pitted and replaced and 4 new cylinders as well.

I wouldn’t mind so much but I suspect the cylinders will need replacing at 1200 hours.

Whereas the local microlight school running c42 get 3000 hours with little more than routine maintenance.

Crankcase cracked, crank out of limits, camshaft pitted and replaced and 4 new cylinders as well.

I hate to sound like a Lyco fanboy (I spent $14k on a replacement crankshaft) but

• cracked crankcase = prob99 a prop strike which has been covered up (or worse, depending on where the crack is)
• camshaft pitted = no flying for a few months at a time (high humidity etc would help too)
• 4 cylinders = abuse, on an O-200 massive abuse

In the US schools, the O-200 nearly always goes to TBO and way past.

Whereas the local microlight school running c42 get 3000 hours with little more than routine maintenance.

There could be non-obvious reasons for that e.g. your O-200 has been rented to anybody who turns up with a PPL issued after 1945 (not suggesting you are doing it now ) whereas the microlight school has much more control and for very good reasons. If you have a new C42 you will be very picky about who flies it.

Geez, the Conti C85 in my 1947 Cessna 140 has NEVER been overhauled and it’s still going strong after 68 years !

A C172P with 160hp(?) might well be a very nice two seat airplane with this Rotax Engine and a wobbly prop. If the Thielert can lift it, this can do it with a lot less weight up front. Possibly no modifications to the fuel system + unleaded fuel which makes the replacement quiet easy. This could be a winner – not everyone needs stunning performance.

The 915iS is 33kg lighter than the O-360 and 50kg lighter than the Thielert option.

Michael wrote:

Geez, the Conti C85 in my 1947 Cessna 140 has NEVER been overhauled and it’s still going strong after 68 years !

Well, in 47 when the dinosaurs where young and hi tech, they also new how to make them. An art that seems to have become lost in more recent years. Seriously, they still make the exact same stuff (more or less), only of poor quality. That is the main difference, a Rotax is new tech at high quality, a new Lyconti is old tech at poor quality.

celtico wrote:

better a jet turboprop

Fortunately, they don’t have any consumption data in their brochure