Turboprop Robin

If memory serves well, Rotax 912 was not more cost efficient than Continental 0-200
Not sure how the much more expensive and complex 916 is supposed to do the trick

thanks for that @etn
Interesting interview by Ed. Would quite fancy such a turbine, not in a Robin, but in my own steed

RV14 wrote:

Rotax 912 was not more cost efficient than Continental 0-200

A new Continental O-200 costs US$ 45k. A new Rotax 912 costs US$ 20k. I think we safely can say that a Continental O-200 is NOT more cost efficient than a Rotax 912. A Continental O-200 is in 915/916 land when it comes to cost.

LeSving wrote:

I think we safely can say that a Continental O-200 is NOT more cost efficient than a Rotax 912.

I think you can say that, and spend your money however you like… but ‘we’ know that almost nobody needs to buy a new O-200 (which is why they are so expensive new) and as a result the cost model in your head is not relevant to ‘us’, thanks very much

I could buy a whole plane with an O-200 attached for $20K and then someday overhaul it for roughly $15K. I didn’t actually do that because I wanted more power so buying an O-320 powered plane for $35K made more sense to me (12 years of flying ago and counting).

Silvaire wrote:

LeSving wrote: I think we safely can say that a Continental O-200 is NOT more cost efficient than a Rotax 912.

I think you can say that, but ‘we’ know that almost nobody needs to buy a new O-200 (which is why they are so expensive new) and as a result the cost model in your head is not relevant to ‘us’, thanks very much

I can buy a whole plane with an O-200 attached for $20K and someday overhaul it for roughly $15K.

@Silvaire, I think that in the UK it would be more like £20K to overhaul…

Not if it was N-registered and you did the overhaul with your own fair hands in collaboration with an A&P who would sign it off.

That’ll be my plan with my O-320 when the time comes unless I’m so old by that time that my hands don’t work any more Its making zero metal but using about a quart every 9 hours, 52 years since it was assembled. I watch it and wait.

Silvaire wrote:

but ‘we’ know that almost nobody needs to buy a new O-200

Nobody “needs” to buy a new 912 either, but most people do because the new ones are not (yet at least) transformed into insanely overprized pieces of metal to fill the pockets of the People’s Republic of China with cash. Anyway, the argument was cost effectiveness, and since “almost nobody needs to buy a new O-200” (due to cost), this pretty much settles that argument. An O-200 is nowhere near the cost effectiveness of a 912: €20k, TBO of 2000 h, overhaul cost of €10k, runs on any sort of gasoline.

But back to turbines. I remembered I had read an article in Kitplanes about the PBS TP. Here it is. This engine is many years old already, so why aren’t there more of airplanes fitting this engine? 200+ hp, weighs less than 70 kg. The main reason is obviously price. I thought perhaps it costs twice as much as the turbojet, but the price is actually printed in the magazine from 2015: about US$ 175k – in 2015. That’s 4 times the price of the PBS turbojet, with the same core turbine (in 2015).

Is a TP four times as cool as a jet? Certainly not, but probably more than 4 times as useful in a normal GA aircraft though. Realistically there is no way these new contenders will be able to make similar sized engines, with these unproven intercoolers (much more complex), and sell them for less than €200k a piece. TurbAero say about US$ 85k in the video, but that doesn’t look very realistic for a working engine (remember a new but ancient tech O-200 costs 45k).

For more fancy stuff, Rotax 915/916 is obviously the way to go. For more (unpractical) coolness, a turbojet is the obvious route. At realistically 4 times the price of a 915/916 what does a TP offers that the 915/916 doesn’t have? There’s only 3 things: jet fuel, the sound and cool factor. What they lack is to actually exist (except PBS which no one want’s due to cost )

@LeSving, your ability to create models that match the conclusion you wish to reach is notable. It’s a common symptom of both over education and isolation The main thing I think you’re missing is that not everybody lives in Norway, where there is little GA infrastructure so little in the way of local engine overhaul resources. So you buy new, and it makes sense for you. You also pay outrageous fuel prices and so a small engine to power the lightest possible plane is what you want to buy.

One of the reasons Rotaxes have never really caught on in different places, where airports might have 500 or 600 individually owned, based aircraft is that they are expensive to buy, there are lots of existing engines and resources to overhaul them around already, and also because Rotaxes are very limited in power. The same is true to a lesser extent for the little Continentals, new ones are expensive too and they don’t much power either. You can build one up for a reasonable sum but they only make 100HP and nowadays new sport planes in the US etc typically need 150 HP or more. Even the Cub guys want more and Lycomings have become the mainstream sport plane engine over the last 40 years, except for European LSA type planes that naturally reflect the issues where they are made.

This reminds me a bit of people saying 250cc and under is the economical future of motorcycling because that’s what sells in volume in the third world. I’m happy to disagree and see joining them as undesirable.

The turbine thing is just a fantasy, I can’t see that discussing it in any detail is a productive use of time.

I don’t know if I must laugh or cry seeing a turbine Robin. It makes no sense to me, apart from giving a « modern » buzz to a company that makes the same airplanes as 50 years ago.
Why they still haven’t a strong proposition of a rotax-based profitable trainer for clubs is beyond my understanding. I guess they must disappear in order for others to really move GA forward (looking at you elixir ).