Turbo Diesel Skyhawk Certified

I wonder if this can longer term help lower training costs. (Assumption Jet-A would be cheaper then avgas)

Tim
 
wonder what the TBO is on the engine?
 
Considering the fuel burn, with half tanks you have 3 hours of range and a decent payload for a trainer. Is the 130ktas cruise realistic or only possible in a dive? I would imagine the service ceiling would be quite a bit higher given the fact the motor up front is turbo'd.
 
wonder what the TBO is on the engine?

2100 hours. But the timing chain and gearbox are still 1200 hour components. Continental announced the increase to 2100 hours last year.

Let's hope this is more successful than the Diesel 182 was.
 
wonder what the TBO is on the engine?
If I recall correctly, the original Thielert diesel engine had a TBR not TBO ... no overhaul during the trial period.
I have no idea what the Continental diesel is ...
 
2100 hours. But the timing chain and gearbox are still 1200 hour components.

Let's hope this is more successful than the Diesel 182 was.

The 182 was based on the SMA engine. This is the older Thielert engine which has had a lot longer to go through the teething pains.
Any links on the TBR/TBO, my quick google only found ones for the STC which are out of date.

Tim
 
The fundamental problem is still the capital cost of $435,000 which my quick and dirty cost shows is about $65,000 more than the old tractor engine model. But what do I know?
 
I don't see how diesel engines can work in the United States until they have TBO's, not TBR's with expensive transmission inspections half through that. Gas is fairly cheap, and not likely to increase very much in the next few years.
 
I wonder if this can longer term help lower training costs. (Assumption Jet-A would be cheaper then avgas)
Nationwide, avgas averages $4.74 while Jet-A is $4.17 according to airnav. That's not enough delta. Also, there are 40% more airports with 100LL than there are with Jet-A.
 
Considering the fuel burn, with half tanks you have 3 hours of range and a decent payload for a trainer. Is the 130ktas cruise realistic or only possible in a dive? I would imagine the service ceiling would be quite a bit higher given the fact the motor up front is turbo'd.

134kts is probably at max altitude and with the FADEC lever full forward. How else could a 155hp airplane outrun a 160hp airplane with just an engine swap?
 
I don't see how diesel engines can work in the United States until they have TBO's, not TBR's with expensive transmission inspections half through that. Gas is fairly cheap, and not likely to increase very much in the next few years.

The costs of the diesel are not trivial. Shops have to spend money to become certified to work on them, the cost of that has to be recovered from a small customer base. The props tend to be composites like the MT, in order to offset the engine weight and absorb the diesel power pulses. These can only be serviced at a small number of locations if blade or hub work is needed. And on it goes.

Had a long discussion about this with the owner of the facility that maintains the DA-42 I posted engine detail pictures on another thread. He likes the airplane but he's had to make a big investment to take on this first diesel engine customer.

One thing that could give it a push is the lead issue in avgas. Ironic given how embroiled in an emissions scandal automotive Diesel engines are presently.
 
Nationwide, avgas averages $4.74 while Jet-A is $4.17 according to airnav. That's not enough delta. Also, there are 40% more airports with 100LL than there are with Jet-A.

If you burn Jet-A, get a fuel card. I believe CAA is running just under a $3 gallon average.

Tim
 
134kts is probably at max altitude and with the FADEC lever full forward. How else could a 155hp airplane outrun a 160hp airplane with just an engine swap?

The 160HP has less power by 5K feet, while the CD-155 maintains power to 18K (I think) before you start to lose power.

Tim
 
134kts is probably at max altitude and with the FADEC lever full forward. How else could a 155hp airplane outrun a 160hp airplane with just an engine swap?

There's a lot of other factors that come into play to determine max speeds. For starters the diesel is water cooled so perhaps the cooling drag is lower? Just a thought.

I believe it was Carrol Shelby that was attributed with the quote: "Horsepower sells cars, torque wins races". ;)
 
134kts is probably at max altitude and with the FADEC lever full forward. How else could a 155hp airplane outrun a 160hp airplane with just an engine swap?

The Austro powered DA40 out cruises its IO-360 sister ship by 10ktas despite a having 20 fewer horses.
 
There's a lot of other factors that come into play to determine max speeds. For starters the diesel is water cooled so perhaps the cooling drag is better? Just a thought.

Looking at the gallery, I think some of this might be true. The inlets are ducted rather than baffled which I imagine would be more efficient.
 
The 160HP has less power by 5K feet, while the CD-155 maintains power to 18K (I think) before you start to lose power.

That depends on whether or not you follow the manufacturer recommendations. Here is a clip from Continental's CD155 web page.

2zdypty.PNG


So for the avgas engine needs to be above 9000 before it starts losing power.
 
Looking at the gallery, I think some of this might be true. The inlets are ducted rather than baffled which I imagine would be more efficient.
I could see a few knots. But ~15kts? Doubtful.
 
I'll wait for the DeltaHawk. No transmission to worry about.
 
Is this new version of the 172 better than the 30 year old version?
 
That depends on whether or not you follow the manufacturer recommendations. Here is a clip from Continental's CD155 web page.

2zdypty.PNG


So for the avgas engine needs to be above 9000 before it starts losing power.

Not sure about you, but I climb at full power, and I cruise around 75%. So the CD-155 will outrun the avgas in normal flying most likely by having more power in the climb.

Tim
 
Is this new version of the 172 better than the 30 year old version?
Yes, because it is NEW!
Jokes aside, Cessna has made improvements over the years in aerodynamics, comfort, sound... Now for what those changes are, you need to talk to a Cessna nut. You also would need to make a value judgement if those changes are worth it to you...

Tim
 
Useful load is a bit low. I guess that's somewhat mitigated by the lower fuel burn.
 
Useful load is a bit low. I guess that's somewhat mitigated by the lower fuel burn.

Considering 24 gallons gets you 3 hours plus VFR reserves you can fit 3 large people in there pretty easily. Pretty good for a (modern) trainer.
 
I could see a few knots. But ~15kts? Doubtful.

Plus a constant speed prop and turbo'd engine...

I'm doubtful too, the cruise number seems high but I'm just answering why the plane would be faster despite 25 fewer horses.
 
Not sure about you, but I climb at full power, and I cruise around 75%. So the CD-155 will outrun the avgas in normal flying most likely by having more power in the climb.

Very true, but I was speaking more towards the claimed 134kts cruise. That's not going to happen at 75%.
 
Plus a constant speed prop and turbo'd engine...

I'm doubtful too, the cruise number seems high but I'm just answering why the plane would be faster despite 25 fewer horses.
It's faster because they probably measured it at a really high altitude and with the FADEC lever at the 100% limit rather than their own 75% recommendation. In other words, 134kts is a "nudge nudge wink wink" number.
 
Nationwide, avgas averages $4.74 while Jet-A is $4.17 according to airnav. That's not enough delta. Also, there are 40% more airports with 100LL than there are with Jet-A.
Fuel burn of the diesel will be a few gph lower than the equivalent gas engine, which will be a far bigger money saver than the price delta per gallon.

Enough to cover for the extra purchase price, maintenance price, and TBR vs TBO? Doubtful.
 
It's faster because they probably measured it at a really high altitude and with the FADEC lever at the 100% limit rather than their own 75% recommendation. In other words, 134kts is a "nudge nudge wink wink" number.

The same way the Cessna TTX is the 'fastest fixed gear single' and the M20 Ultra the 'fastest piston single'. They all use that trick.
 
For the under 200 hp portion of the fleet, I think something that burns a mogas derived fuel makes more sense. Around here 90 octane ethanol free mogas is becoming common, and can be had for about $2.70 per gallon at land based filling stations. Every marina has it as well, but it goes for about a dollar more on the water.
 
Many have been waiting for that "next year" engine for a long time.

Complete hearsay, but what I heard is that Deltahawk is running into nitpick certification issues not issues with the core engine. In addition, they now have a rather wealthy family backing the company, and they seem to be making solid progress. Compare that to a decade ago when they struggled for cash....

Tim
 
For the under 200 hp portion of the fleet, I think something that burns a mogas derived fuel makes more sense. Around here 90 octane ethanol free mogas is becoming common, and can be had for about $2.70 per gallon at land based filling stations. Every marina has it as well, but it goes for about a dollar more on the water.
Better yet, if it's a clean sheet design something that can handle regular mogas, with the 10-15% ethanol blend. That eliminates the need for a special blend and special infrastructure.
 
BTW, Russians continue to persist with the Yak-152 program. The 2nd airplane was exhibited at MAKS 2017. It continues to use the German RED diesel. The weird thing about it, the rated power is 500 hp in the RED A03T version. I don't know whose bright idea it was to train cadets on a 500 hp airplane. Cannot be very cheap.

The Ministry of Defense reduced their order from 300 to 150 units. But DOSAAF (their kinda CAP) promised to buy 105.
 

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Better yet, if it's a clean sheet design something that can handle regular mogas, with the 10-15% ethanol blend. That eliminates the need for a special blend and special infrastructure.
One of the light sport planes I rent can use 91 octane mogas. I found out that with gas that contains ethanol, water in the gas looks different that it does with avgas. The water goes into solution with the ethanol, creating a yellow layer, and when the amount of water becomes more than the ethanol can hold in solution, the excess water separates out at the bottom. See the attached article:

http://www.lcbamarketing.com/phase_separation_in_ethanol_blen.htm
 
2100 hours. But the timing chain and gearbox are still 1200 hour components. Continental announced the increase to 2100 hours last year.

Any guess to the cost of those components, then what would be the cost at TBR? Begs the question of how many Thielert's are out there (mostly in Europe)?
 
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