H

Hack

Active Member
Many of you have probably heard about this engine going into the $0.5M C-182. If not google it and you will get the poop.
Just out of curiosity, has anyone heard of an engine of this type that might fit into an envelope similar to IO 320/360?
 
Maybe my memory is faulty (distinct possibility) but I seem to recall a version of the french Socata singles (Trinidad, I believe) with a diesel in place of the usual 360. Don't remember who made it, though. More recently, the Thielert Centurion engines used in the Diamond twin were retrofitted into a 172 at one point; very compact small-displacement turbo-diesel and very fuel-efficient.
 
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gerrychuck said:
More recently, the Thielert Centurion engines used in the Diamond twin were retrofitted into a 172 at one point; very compact small-displacement turbo-diesel and very fuel-efficient.
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But plagued with very high cost, maintenance, and a short TBR (time between REPLACEMENT - no overhaul allowed). This new development, while still overpriced, is at least in the right place with efficiency and ability to reach TBO versus TBR. Time will tell.
 
pmccoy said:
Here is the link to another story on this. It states the engine will burn 30 to 40 percent less fuel. Wow!

http://www.gascaviation.com/blog/2012/07/cessna-unveils-turbodiesel-182
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The O-470's in the "older" C-182s burned 12-14 gph. Probably 13-15 gph in the newer Lyc powered Skylanes. At a posted 11 gph for the deisel, that's not really a 30-40% savings. Jet A is cheaper and more available, though.

I also can't imagine that the airplane will be (only:eek:) $515,000. Aren't the regular current C-182s going for more than that new now?
 
The O-470 in my Cessna 180 typically burns 9 to 11 gph depending on altitude. When I need oxygen, it's usually lower by around 1 to 1.5 gph.

Cruise is about 140 kts.

The only time I saw 14 gph in "cruise" was when I was racing someone.

Dave
 
Would love to put one in My RV-10

6 years ago when I was just dreaming of building, I had always though I would put a turbo normalized diesel or other modern engine in the plane I built. I know enough now that I am not holding my breath waiting on a firewall forward kit for my 10 that will be done end of next year. Maybe in 10 years when I need to do an overhaul.
 
I don't understand the part about Lycoming's involvement in this announcement. Continental, not Lycoming was involved with the SMA to develop it further after multiple problems in use reaching anywhere close to TBO/TBR.

This engine is limited to 12,000 feet due to turbocharger N1 limits as well so I don't see how it will replace the SI turbo 182. Finally, the current cost will not allow it to save any money over its life cycle as acquisition costs are up front and fuel costs are spread out over the operating time. This assumes Continental can actually make the changes to get the engine to run to TBO/TBR reliably.

The diesel makes sense in places with poor avgas availability, high avgas costs and only when the manufacturer can offer the engines at a price close to the SI engines they replace and get equal or better reliability and TBO out of them. Historically the original Thielert and SMA did none of these things. Hopefully Continental or Lycoming can turn this around with some hard work, good engineering and extensive testing.
 
rv6ejguy said:
This engine is limited to 12,000 feet due to turbocharger N1 limits as well so I don't see how it will replace the SI turbo 182. Finally, the current cost will not allow it to save any money over its life cycle as acquisition costs are up front and fuel costs are spread out over the operating time. This assumes Continental can actually make the changes to get the engine to run to TBO/TBR reliably.
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Per the manufacturer the service ceiling is now 20k. I think they started building their own turbocharger. TBO is 2400hrs
 
dhammer said:
Per the manufacturer the service ceiling is now 20k. I think they started building their own turbocharger. TBO is 2400hrs
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That makes it much more useful in the mountains.

The TBO was initially 2000 hours but most of the engines were being replaced within 300-600 hours due to oil leaks cause by case fretting. I am guessing a redesign of major components was required to address this sort of issue.

I put little faith in published TBOs on new engine designs, quite meaningless until at least a couple dozen examples make it there without attention. The Lycoming TIO-540-AE2A was a prime example of a certified engine consistently falling well short of TBO as was the Thielert aero diesel. Only time will tell if the problems have been licked and 2400 hours is a reasonable number. If so, the engine would be very useful in Europe and Africa where avgas is scare and/ or outrageously priced.
 
Just doing a few calcs here and that would be some impressive turbocharger to maintain the full TO power MAP of 90 inches at 20,000 feet. Pressure ratio of 6.5 to 1. No single stage turbo is capable of that in this mass flow range to my knowledge. Even at high cruise power the PR would be 5 to 1 which is about what the very best racing units can put out over a narrow range of flows right at their N1 limit.

I wonder if they have developed a 2 stage system?

The intercooling requirements are staggering at these PRs though as the compressor discharge temps are 400-500F depending on inlet temp and compressor efficiencies.

An interesting challenge. Curious how they accomplished this.
 
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They would've had to raise the compression ratio and lower the boost to realistically accomplish that kind of critical altitude. On the other hand, if they just made that the service ceiling, not the critical altitude? Maybe it's possible?

That said, this engine has been STC'd for 182's for 5 years or so now, whats the big news? For a while, Cessna offered the 172 with the Theilhart from the factory, I didn't see that selling well either... and it didn't.

There is a reason why Diamond doesn't sell the DA40D here, and why they have a Lyc powered DA42. The economics don't make sense on this side of the pond.
 
Critical altitude is 10,000 ft

According to the manufacturer's brochure, the critical altitude is 10K ft and the certified ceiling is 20K ft.
http://www.smaengines.com/IMG/pdf/fiche_SMA_ang.pdf
How that translates to real world flying? I have no idea since I've never flown a turbocharged aircraft.

I would love to see one of the diesels out there become a reliable alternative for builders who struggle to get avgas abroad. I can think of several missionary aviation organizations that might consider a diesel powered aircraft for some of their remote operations.
 
fmarino1976 said:
According to the manufacturer's brochure, the critical altitude is 10K ft and the certified ceiling is 20K ft.
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This makes more sense and is doable with off the shelf, modern turbos.

The killer for diesels at high altitude is the high MAP required to make hp compared with SI engines. I believe they run 90 inches on the SMA for takeoff power and 60-70 in cruise!
 
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