It isn't so much the frequency of major failures in turbines, which statistically are lower.

But the consequences of drawing the short straw can be so much more costly. I ultimately know the most costly possible failure of a TSIO-550, and I can, with some sweat and discomfort, afford that.

But I can't comfortably do that with a PT6, do the same. It's just too much for my pocket.

The other thing is the usage model. There's an old saying, "A job needs a turbine, and a turbine needs a job.".

There's a lot of logic there. I don't use my airplane enough to put enough flight hours to make the calendar schedule items worthwhile. Nor do I really need to be anywhere bad enough that $1000/hr or more, would be worth the cost.

Turbine engines have very few calendar based items. The maintenance schedule is mostly hours and cycles.

The only calendar inspection on my JT15D is a 2 year light check of ignitors, bleed valves, minor look over. Takes 2 hours for both engines, so not a big deal.

Everything else is hours or cycles.

Turbines stand up much better to occasional or light use than pistons.

Mike C.

This gets complicated...
I was debating a MU-2 or an Aerostar.
I chose Aerostar because based on the cost of the maximum probable maintenance event.

I thought the MPME on the aerostar would be a windshield (40K) or an engine 50K.
I thought the MPME on an MU2 while less likely would be a new engine at $500K.

I ended up having a 125K event on my Aerostar, and I also learned that used turbine engines (for 125K or so for the MU2 ) were a thing.

If I had it to do over I'd go with the MU2.
I've now spent >~500K on an airframe that is probably worth $250K on a good day.
YMMV.

Larry I know this is not what you meant, but the most costly failure of a single engine turbocharged piston is loss of the aircraft when you park it off airport. That happens all too often when the main seal between two halves of a turbo fails. That allows the engine oil to be sucked into the turbo resulting in rapid engine failure. When I owned a Piper Mirage I read about friends with this type of failure all too often.

It isn’t a Lycoming or Continental issue. It happens to both because they use similar turbo design. Until someone creates a turbo piston engine with a separate oil reservoir for the turbo I never want to own one again. The only thing worse than a turbo piston engine is two of them on a twin engine airplane.

Best case the airplane glides to an airport. The PA46 is a wonderful glider with long wings so there is a lot of success. Then your budget is hit with a complete replacement without a core.

Medium case is successful off airport landing. Your budget is ok because now it’s an insurance claim. Your family will never want to fly again.

Worst case is a fatality.

Even outside of the loss of oil situation, turbo piston engines simply wear out. Top overhauls, turbo replacement, early complete overhaul are part of the ownership experience.

My years of PA46 show me that owning a Meridian is overall not more expensive than owning a Malibu or Mirage (ignoring acquisition cost).

Well, my direct experience with 2 Meridians Vs 4 Malibu/Mirages is just the opposite : BOTH Meridians had major non-scheduled turbine repairs , both over $200K, BEFORE even reaching mid-life (1750H TiS) . The Malibu/Mirages had nothing but cylinder changes in between engine overhauls over much longer lives.

That sums up step-up turbine economics.

Ignoring my failure at wining the lottery, a CJ4 would be a nice ride
to go in my hanger with the Custom cub, P-51, Stemme, Turbine Beaver and Extra-300.

Honestly, I'm not speaking of crashing the airplane, that's a different story. The rate of crashing is overwhelmingly dominated by pilots, not the failure of powerplants. The GA numbers hover around 10:1, human-failure vs. mechanical-failure for death and injury. Besides, assuming I survive, the insurance company owns the plane from the moment the engine stopped. After that, I'm only focused on living.

I can conceivably, purchase a replacement engine, should it fail in such a way as to condemn it.

I can't do that as easily with a turbine.

I have friends with PT-6 powered aircraft, who've been faced with unexpected 6-figure bills following inspections. Though in some cases, a second opinion offered less-expensive ways to remedy things.

The "short-straw" engine issue aside, there are a lot of extra costs going the SETP route, like acquisition cost, recurrent training requirements, insurance, fuel burn, etc. Or the hourly engine programs where applicable as a means to contain the surprise costs.

For my typical journey of 350nm, the I'm running about 200-205kts true at an economy fuel burn of ~15gph.

The Meridian burns a good bit more fuel, but isn't wildly faster. It's 18 minutes faster, but 51 gallons of Jet-A vs. 25 gallons of 100LL on the same trip.

If I had the money to spend, I'd be right there in that Citation or Vision Jet or TBM, etc.

I haven’t really noticed any significant difference between my overall operating costs of the turbine and the piston PA46. Outside of things related to hull value. We run up to 400 hours on our M600, which would be 535 hours equivalent time on a mirage or M350 given airspees. That would be an oil change about every two weeks if you are a 25 hour type. That is a lot of work, time and money. But we’ve had no real issues with our engine. Might have to tune up or replace an accessory every now and then, and there’s expendables like igniters and fuel injector maintenance. But those things aren’t expensive. It is so nice just to go out to the plane, hit start in the edge. It just starts every single time and never waivers in flight. Same sound, same RPM, same exact temps every flight. The Lycoming is a great motor as far as reliability very resistant to catastrophic failure, but nothing breeds confidence like the unwavering hum of the PT6. I loved my two piston PA46s, but the turban is just a whole different level of reliability

Since the title says--- Low cost turbine, I found one-
Neal is advertising this -https://www.controller.com/listing/for-sale/245335175/2001-piper-meridian-turboprop-aircraft. Can't beat this for $700K.

This is close to the same plane I have. Outside of the horrible STEC 550 it has that I replaced with the even worse 3100. :-)

The meggitts are not bad to fly behind. The interior is essentially the same as off the line now, and so is the engine. Jump in the water is warm....

No gross weight increase and engine over TBO. The price reflects that

Larry I know this is not what you meant, but the most costly failure of a single engine turbocharged piston is loss of the aircraft when you park it off airport. That happens all too often when the main seal between two halves of a turbo fails. That allows the engine oil to be sucked into the turbo resulting in rapid engine failure. When I owned a Piper Mirage I read about friends with this type of failure all too often.

It isn’t a Lycoming or Continental issue. It happens to both because they use similar turbo design. Until someone creates a turbo piston engine with a separate oil reservoir for the turbo I never want to own one again. The only thing worse than a turbo piston engine is two of them on a twin engine airplane.

Best case the airplane glides to an airport. The PA46 is a wonderful glider with long wings so there is a lot of success. Then your budget is hit with a complete replacement without a core.

Medium case is successful off airport landing. Your budget is ok because now it’s an insurance claim. Your family will never want to fly again.

Worst case is a fatality.

Even outside of the loss of oil situation, turbo piston engines simply wear out. Top overhauls, turbo replacement, early complete overhaul are part of the ownership experience.

My years of PA46 show me that owning a Meridian is overall not more expensive than owning a Malibu or Mirage (ignoring acquisition cost).

No gross weight increase and engine over TBO. The price reflects that

Should add something like a T-38 also.