Cessna Skyhawk goes Diesel
Cessna Skyhawk goes Diesel
Just announced that from 2008 you will be able to buy a Jet-A sipping Skyhawk. Best GA news since the G1000.
Piper and the rest better get a move on, Diesel power is going to kill AVGAS stone dead.
Piper and the rest better get a move on, Diesel power is going to kill AVGAS stone dead.
I've heard the Aeroclub of WA has a few of these on order. Good on 'em! 
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The question should be, will they ever make life?
Any aero engine that requires electrical power just to run is somewhat of a concern - an engine built by computer boffins.
How many times have you had spat an alternator belt, or had regulator problems? "ahh but we've put some spare batteries in the he back" they say
.......not in my plane.....
awful, awful things
Any aero engine that requires electrical power just to run is somewhat of a concern - an engine built by computer boffins.
How many times have you had spat an alternator belt, or had regulator problems? "ahh but we've put some spare batteries in the he back" they say
.......not in my plane.....
awful, awful things
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From the Cessna website
FG, from my interpretation of the Thielert website (Ich kann nicht Deutch sprechen) the TBO for this donk is 2400hr. Couldn't be any shakier than LAE
The Skyhawk TD (turbo diesel) will feature a Full Authority Digital Engine Control (FADEC) equipped Thielert Centurion 2.0 liter engine. The DOHC (double overhead camshaft) in-line four-cylinder turbocharged engine develops 155 horsepower, is certified to operate on Jet-A fuel, is liquid cooled and drives a composite three-blade constant speed propeller.
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Quote
"The question should be, will they ever make life?
Any aero engine that requires electrical power just to run is somewhat of a concern - an engine built by computer boffins.
How many times have you had spat an alternator belt, or had regulator problems? "ahh but we've put some spare batteries in the he back" they say
.......not in my plane.....
awful, awful things "
Wouldn't you just hate to have any sort of up to date technology in Aussie GA!! heaven forbid!!
The fact is most modern biz jets and basic airliners have systems that could make life so much easier and safe for GA - let us move past the 1970's technology!!
"The question should be, will they ever make life?
Any aero engine that requires electrical power just to run is somewhat of a concern - an engine built by computer boffins.
How many times have you had spat an alternator belt, or had regulator problems? "ahh but we've put some spare batteries in the he back" they say
.......not in my plane.....
awful, awful things "
Wouldn't you just hate to have any sort of up to date technology in Aussie GA!! heaven forbid!!
The fact is most modern biz jets and basic airliners have systems that could make life so much easier and safe for GA - let us move past the 1970's technology!!
Grandpa Aerotart
The technology is great...but at what cost?
To date diesel technology has been a non starter cost wise unless operating large numbers of hours/annum as in a large flying school type setting...avgas is still too cheap for significant diesel aftermarket penetration. That may change...but there is a least as good a chance that we will see oil prices fall again in the next few years and deisel will once again go on the back burner.
FADEC has thus far been still born for the same reasons...it is just not cost effective in it's current iterations.
You can whinge all you like about 1970s technology but unless more modern technology offers real savings, and by real I mean to the average owner whose aeroplane flys 100 hrs/annum, it will not be taken up.
If Theilert built an diesel aftermarket conversion for my Bonanza (they don't because the nose bowl design leaves not enough room) it would be at a priced point approximating their V8 350hp model. The same engine they CAN put in a C206/210. Last I looked it would be well over Euro100K to do a conversion.
Eu100k=Aud157k/2400TBR = AUD$65/hr engine cost.
Engine allowance for my Bo is < AUD$20/hr.
The price delta between avgas and avtur is about 10%.
That is why '1970s' technology is still going strong...because so far nothing can touch it for economy of operation.
And avgas is not going away any time soon.
To date diesel technology has been a non starter cost wise unless operating large numbers of hours/annum as in a large flying school type setting...avgas is still too cheap for significant diesel aftermarket penetration. That may change...but there is a least as good a chance that we will see oil prices fall again in the next few years and deisel will once again go on the back burner.
FADEC has thus far been still born for the same reasons...it is just not cost effective in it's current iterations.
You can whinge all you like about 1970s technology but unless more modern technology offers real savings, and by real I mean to the average owner whose aeroplane flys 100 hrs/annum, it will not be taken up.
If Theilert built an diesel aftermarket conversion for my Bonanza (they don't because the nose bowl design leaves not enough room) it would be at a priced point approximating their V8 350hp model. The same engine they CAN put in a C206/210. Last I looked it would be well over Euro100K to do a conversion.
Eu100k=Aud157k/2400TBR = AUD$65/hr engine cost.
Engine allowance for my Bo is < AUD$20/hr.
The price delta between avgas and avtur is about 10%.
That is why '1970s' technology is still going strong...because so far nothing can touch it for economy of operation.
And avgas is not going away any time soon.
Chukkie, young fellow - what ever gave you the idea today's Continental and Lycomings are 1970's technology???
In the 1970's we used to say they were 1940's technology. I think you will find your primitive 520 clunker's heritage is rooted in the post war 1940's!
Two points you've overlooked with the diesel engine:
The PT6 started life at 2,500 hours TBO and the common opinion forty years ago was to stick with pistons as they were more cost efective. Then it's TBO grew - some of the PT6-27's and PT6-34's you've flown were on condition and had up to 10,000 hours engine life.
2,500 hours is not even run in for a diesel. The diesel engine will go the same way as the PT6 - my guess it will hit 4,000 hours plus TBO in a very short period, perhaps on condition in commercial applications, with lower overhaul costs.
I seriously doubt fossil fuel will significantly reduce in price - resulting in bio fuel becoming a very cost effective alternate. Like the PT6 AG series engines, I'm sure the diesel will be totally happy on cheaper alternate and bio fuels.
Now, if your Bonanza engine could be overhauled at, for example, 20% or so lower cost, at 4,000 plus hours, after running on fuel probably 20% cheaper, would that change your equation?
Peter. The FAA destroyed the Porsche engine during certification of the Mooney installation, some say very intentionally to protect the "home market".
The Porsche engine cost was a prohibitive factor but it would have been an extremely nice and effective alternate sports aircraft engine.
In the 1970's we used to say they were 1940's technology. I think you will find your primitive 520 clunker's heritage is rooted in the post war 1940's!
Two points you've overlooked with the diesel engine:
The PT6 started life at 2,500 hours TBO and the common opinion forty years ago was to stick with pistons as they were more cost efective. Then it's TBO grew - some of the PT6-27's and PT6-34's you've flown were on condition and had up to 10,000 hours engine life.
2,500 hours is not even run in for a diesel. The diesel engine will go the same way as the PT6 - my guess it will hit 4,000 hours plus TBO in a very short period, perhaps on condition in commercial applications, with lower overhaul costs.
I seriously doubt fossil fuel will significantly reduce in price - resulting in bio fuel becoming a very cost effective alternate. Like the PT6 AG series engines, I'm sure the diesel will be totally happy on cheaper alternate and bio fuels.
Now, if your Bonanza engine could be overhauled at, for example, 20% or so lower cost, at 4,000 plus hours, after running on fuel probably 20% cheaper, would that change your equation?
Peter. The FAA destroyed the Porsche engine during certification of the Mooney installation, some say very intentionally to protect the "home market".
The Porsche engine cost was a prohibitive factor but it would have been an extremely nice and effective alternate sports aircraft engine.
Last edited by Torres; 5th Oct 2007 at 21:41.
The scoffers of diesel technology are technical luddites. joing the ranks of the flat earth society, the people who said the wright brothers will never fly, and the ones who said Japanese 4 cylinder cars would take over the world.
I've heared recently that the worlds majour green groups are getting ready to take on Avgas and will push for punitive taxes for using TEL
I've heared recently that the worlds majour green groups are getting ready to take on Avgas and will push for punitive taxes for using TEL
AeroDiesels. One thing that everyone has not looked at is long term availability. Theilert are using a benz auto diesel as the base engine in both four and eight cylinder iterations. There is no guarantee that Mr Benz will continue to keep this particular model engine line running into the forseeable future. As much as I desire the uptake of new technology the single impediment to penetration of new tech is the longevity of aircraft in service. New tech is synonymous with turnover of the ENTIRE fleet in relatively short time spans. CC's $100k conversion would become rather prohibitive if every ten years a new conversion would be required to uptake the next version of a new autodiesel engine. Parts availability would depend on the auto market. Parts made by aftermarket manufactureres would play havoc with authenticity issues for TSO'd engines in certified aircraft.
Looking at the development history of auto diesels, they have come a long way from noisey, smelly, rough, heavy low power versions of even ten years ago. The current line of EURO 4 compliant engines are a technological marvel of design. Light weight, high torque, high power and LOW FUEL BSFP figures are making them very desirable as candidates for aircraft engines.
What is needed for the aviation industry is a dedicated engine line that will continue for a considerable time frame, that is upgradeable with regard to ECU and injection units, upgradeable with piston and head design. that continues with the same basic dimension but incorporates the latest techniques in aluminium casting to continue to lower weight without compromising strength. A tall order.
The reason why we still have dinosaur engines is because we cannot afford to make the GA fleet obsolete. Excepting the latest adaptation from Mr Cessna,Cirrus and Lancair, the entire fleet is technology from the post war years. What would be desireable would be an airframe to match the tech advances of modern engines with better aerodynamic properties than an aluminium brick.
Looking at the development history of auto diesels, they have come a long way from noisey, smelly, rough, heavy low power versions of even ten years ago. The current line of EURO 4 compliant engines are a technological marvel of design. Light weight, high torque, high power and LOW FUEL BSFP figures are making them very desirable as candidates for aircraft engines.
What is needed for the aviation industry is a dedicated engine line that will continue for a considerable time frame, that is upgradeable with regard to ECU and injection units, upgradeable with piston and head design. that continues with the same basic dimension but incorporates the latest techniques in aluminium casting to continue to lower weight without compromising strength. A tall order.
The reason why we still have dinosaur engines is because we cannot afford to make the GA fleet obsolete. Excepting the latest adaptation from Mr Cessna,Cirrus and Lancair, the entire fleet is technology from the post war years. What would be desireable would be an airframe to match the tech advances of modern engines with better aerodynamic properties than an aluminium brick.
Last edited by OZBUSDRIVER; 6th Oct 2007 at 04:02.
Grandpa Aerotart
Torres I know the genesis of the technology of the engine bolted to my Bo...someone else used '1970s' so I did too rather than waste bandwidth.
Don't forget too that a diesel in a car is running at a small %, maybe 20%, of rated power while an aero version will be running at more like 65-75% all the time and 100% on takeoff...car engines never see these stresses.
While diesel tachnology is excellent I cannot see the economies of scale making it cost effective..and if it aint cost effective aircraft owners won't make the switch.
Much is made of dangers associated with TEL..what is never stated by the greenies is how miniscule the amount of TEL in avgas is, 0.56 grams/liter, or how little avgas is used compared to normal motor fuels, way less than 1%, and how that car fuel contains chemical compounds that are FAR MORE dangerous than TEL.
I was initially really excited about the promise of diesel technology...then I did the numbers.
To make a statement that oil prices are never coming down again requires you to believe the 'peak oil' hype in the media and ignore the facts.
The facts are that we have used less than 2% of current proven oil reserves in the entire 'oil age', i.e. in the last 120 odd years. At current usage rates we have 1000s of years of oil left...assuming we don't find a single additional drop of the stuff....and they continue finding it all over the fecking place.
I keep reminding myself that we have probably only 5 years to wait before the earth starts cooling at a rate that the IPCC can't ignore (or hide) and the entire environmental movement loses ALL credibility...I look forward to the day with undisguised glee
Don't forget too that a diesel in a car is running at a small %, maybe 20%, of rated power while an aero version will be running at more like 65-75% all the time and 100% on takeoff...car engines never see these stresses.
While diesel tachnology is excellent I cannot see the economies of scale making it cost effective..and if it aint cost effective aircraft owners won't make the switch.
Much is made of dangers associated with TEL..what is never stated by the greenies is how miniscule the amount of TEL in avgas is, 0.56 grams/liter, or how little avgas is used compared to normal motor fuels, way less than 1%, and how that car fuel contains chemical compounds that are FAR MORE dangerous than TEL.
I was initially really excited about the promise of diesel technology...then I did the numbers.
To make a statement that oil prices are never coming down again requires you to believe the 'peak oil' hype in the media and ignore the facts.
The facts are that we have used less than 2% of current proven oil reserves in the entire 'oil age', i.e. in the last 120 odd years. At current usage rates we have 1000s of years of oil left...assuming we don't find a single additional drop of the stuff....and they continue finding it all over the fecking place.
I keep reminding myself that we have probably only 5 years to wait before the earth starts cooling at a rate that the IPCC can't ignore (or hide) and the entire environmental movement loses ALL credibility...I look forward to the day with undisguised glee
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Compression ignition the way to go?
Interesting Cessna went for the Theilert when SMA have the SR305 which is an opposed 4@ 230hp and was developed for the 182.
good point about the availability of cores for the centurion into the future,if I understand it correctly its a swap an engine not a rebuild at TBO.
Can't hurt to explore the technology again with modern materials.
Modern diesel engines are electronically controlled reliable fuel efficient units,and many like in construction equipment run full rated hp for most of their life,which is often in excess of 10,000 hrs trouble free.
As Torres has pointed out I think the TBO numbers are conservative but will extend as reliability is proven.
good point about the availability of cores for the centurion into the future,if I understand it correctly its a swap an engine not a rebuild at TBO.
Can't hurt to explore the technology again with modern materials.
Modern diesel engines are electronically controlled reliable fuel efficient units,and many like in construction equipment run full rated hp for most of their life,which is often in excess of 10,000 hrs trouble free.
As Torres has pointed out I think the TBO numbers are conservative but will extend as reliability is proven.
Ozbusdriver
The centurion 2.0 engine block is now made by an outside OEM contractor, the basic design (as in architecture)is from Mercedes but it is now a scratch built aircraft engine.
As for electronics, I was told by the Continentalk FADEC rep that the cpus, computers etc for aircraft engines are now listed as comodity items, which means, that they must be supported for something like 50 years. This is done whena company has such a strong penetration into a market that should it everything is dependant on it and should it withdraw support or production it would mean the end of civilisation. So they are compelled to support it. I think Microsoft is in that situation with windows.
Isnt Air Newzealand about to trial biofuel in a 747-400?
The centurion 2.0 engine block is now made by an outside OEM contractor, the basic design (as in architecture)is from Mercedes but it is now a scratch built aircraft engine.
As for electronics, I was told by the Continentalk FADEC rep that the cpus, computers etc for aircraft engines are now listed as comodity items, which means, that they must be supported for something like 50 years. This is done whena company has such a strong penetration into a market that should it everything is dependant on it and should it withdraw support or production it would mean the end of civilisation. So they are compelled to support it. I think Microsoft is in that situation with windows.
Isnt Air Newzealand about to trial biofuel in a 747-400?
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Originally Posted by Torres
...with lower overhaul costs
Don't forget too that a diesel in a car is running at a small %, maybe 20%, of rated power while an aero version will be running at more like 65-75% all the time and 100% on takeoff...car engines never see these stresses.
When you mention the aircraft engine is running at 100% power on take off, that is 100% of developed power at a specific governed maximum RPM, not 100% of engine capable power? Indeed, the O-480's installed in USAF GPUs ran at 4,000 RPM, not around 2,500 governed RPM as they would in an aircraft installation.
I seem to recall the Lycoming 540 operated at far higher RPM and higher power output in certain helicopter installations, than it did in fixed wing installations. What may be 100% power in a fixed wing aircraft may well be only 80% power, or less in a rotary wing installation?
The Standard Motor company engine in my restored Ferguson tractor develops only 28.2 BHP at a governed maximum 2,400 RPM and runs at around 80% power in normal agricultural applications. The same engine in a Triumph TR4 sports car develops 100 BHP at 4,600 RPM - four times the power at double the maximum RPM.
Your IO520 is 520 cubic inch - 8.520 liters - and only develops a mere 300 HP? Because it is very conservatively governed to that limit and that is all the power you need to fly your Bonanza. Any greater RPM and thus power output, is unnecessary, would result in excessive prop RPM and possibly compromise reliability.
Industrial and marine diesels exceed 35,000 hours trouble free engine life. Heavy road transport engines exceed 20,000 hours life. Even the humble diesel Landcruiser is good for at least an 8,000 hours (500,000 kms) trouble free life.
I suspect aeronautical compression ignition engine applications will mature into a cost effective life well in excess of 4,000 hours - with the added benefits of peak torque at far lower engine speeds than traditional spark ignition aircraft engines, far lower specific fuel consumption per horse power output, greater reliability and far lower in service maintenance costs.
Just my opinion - probably not even 2 cents worth?
Last edited by Torres; 6th Oct 2007 at 06:05.
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Theilert say "the engine has been designed on the basis of tried-and-trusted components from automotive production. By using ready-developed components from the automotive industry, we reduce our development costs." Not sure if that means "we use automotive components" or "the design is based on experience with automotive components". Never the less, Theilert own Superior Air Parts and manufacture Lycoming and Continental bits, including cranks, so one would assume they know what they're on about.
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Originally Posted by Brian Abraham
By using ready-developed components from the automotive industry, we reduce our development costs...
AVGAS is getting hard to come by in some remote places, and as well as the Pacific islands.
If it keeps going that way, then a lightie that can run on JET A might be the way to go
If it keeps going that way, then a lightie that can run on JET A might be the way to go