They should have entered the experimental market first and then tried to certify their engines as Ross seems to have alluded to.
Where does the $62+ figure come from? I couldn't find it on their website, was it quoted at Oshkosh?
Part of that is that they start off by claiming a $40k initial purchase price for a IO360 - which is way above any price I've seen advertised anywhere, ever, and then they add a turbonormalizing system at $11k to the 360, which seems to be a SWAG price to me.
A few more things to consider:
1. Diesel / JetA1 is currently available all over the world, whereas avgas is much more scarce.
2. The military is moving steadily towards all heavy fuels.
3. The US is the one of the only countries still in love with gasoline. We're crazy about gasoline hybrid cars while Europe and other countries are far more efficient and clean with diesel technology. The 2009 Green Car of the Year is not a Toyota Prius, it's a Volkswagen Jetta TDI. The diesels racing in f1 events were whipping the gasoline cars so bad that their fuel tank capacity had to be limited just to make it fair.
4. There was a time, not so long ago, when you wouldn't even consider buying a diesel pickup because they were underpowered, smokey, hard-starting pigs. Now, if you want to pull anything, you'd be a fool not to. Diesels start better, pull leaps and bounds better, and are cleaner than gas engines, not to mention more efficient. The truck buying public of today has no problem shelling out an extra $5-7K for the diesel option.
5. While the Swift fuel may be an excellent alternative for Avgas, the technology still developing, as mentioned. Biodiesel is already available, with new and better technology coming all the time. I've got a good friend who is developing a very large Biodiesel plant here in 'Vegas. From conversations with him, the biggest problem with renewable fuels is that as they come on line, the OPEC nations lower their prices to the point that renewables can't begin to compete, so the development slows or halts. Then there's the issue with govt subsidies and using our food-producing farm ground to produce fuel. Needless to say, it's going to be awhile before we're running on renewable fuels. But when we do, diesel (bio-diesel or whatever) will most likely still be more widely available at less cost than Avgas or it's replacement.
6. Diesels are generally more reliable and longer-lasting than gasoline engines. Diesel is also much safer. Not only is it less flammable than gasoline, the exhaust fumes won't kill you.
Do I sound like a diesel freak or what?
Kurt Goodfellow
RV9/WAM120 diesel - flying
An apples to apples comparison of the BMW 335i SI turbo and 335D CI turbo, both with 3L engines, shows the gasoline engine a full second quicker 0-60, 6 mph faster in the quarter mile and running only 8.5 psi boost compared to 26.8 on the diesel. Fuel economy was 3-4 mpg better on the diesel but this was negated from a cost standpoint due to diesel fuel costing 15-20% more in the US.
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Diesel is cheaper these days..
The cost of diesel fuel at the moment, is 10 cents or more....... less than un-leaded in many parts of the U.S. This is what it was about six years ago, when I purchased my first diesel pickup. Of course a year ago, they were selling diesel for more than premium un-leaded fuel.
Diesels make sense as prime movers where weight is of little concern- trains, ships, heavy trucks, maybe even cars and possibly in aircraft where cost and availability of gasoline is a factor.
Like I said, any time you want to haul something heavy up a grade, I'll bet a years pay that a turbo SI engine will easily out accelerate a turbo CI engine of the same displacement. There is simply no comparison to area under the curve between the two.
There are some 2.5L SI drag cars producing 1400hp and 800 lb/ft running low 6s these days.
Certainly no diesel can match the specific output of the turbo era F1 cars (1000hp/L) or even approach a fraction of the 6500+hp and 4500+ lb/ft. that Top Fuel engines produce these days on a cubic inch basis or in ETs or trap speeds.
For production cars, the Ultimate Aero shows what a modern SI turbo engine can do- 380 cubic inches 1183+hp, 1094+ lb.ft., 0-60 in 2.7 seconds, 1/4 mile at 9.9 and is the fastest production car in the world at 255mph.
An apples to apples comparison of the BMW 335i SI turbo and 335D CI turbo, both with 3L engines, shows the gasoline engine a full second quicker 0-60, 6 mph faster in the quarter mile and running only 8.5 psi boost compared to 26.8 on the diesel. Fuel economy was 3-4 mpg better on the diesel but this was negated from a cost standpoint due to diesel fuel costing 15-20% more in the US. The diesel also requires urea injection to meet 50 state emissions standards. For a boost vs. torque and hp comparison, Dinan mods bring the 335i hp to 392hp and torque to 429 lb/ft at only 13.2 psi (still half the boost of the diesel) on pump fuel and with full factory warranty intact. This is 127 more hp and 4 lb/ft more than the diesel. No doubt the diesel can be pumped up as well but I'm trying to illustrate the point that diesels do not have high torque because they are diesels, it is all due to boost pressure.
High boost equals high torque on both CI and SI engines. The race Merlins make close to 7000 lb/ft at 145-150 inches (2 stage supercharger). The 550 Conti in Mike Dacey's Super Sport Venture makes 1400 lb/ft at power peak rpm running 75 inches.
No doubt there are people who will pay a premium to have a diesel engine whether it is in their car or aircraft because they like them. Do they make economic sense in overall costs? Probably not in North America currently. In Europe, payback on the initial high cost of a diesel would be far more rapid and therefore probably worth it if engine life is close to the typical 2000 hours on a Lycoming.
While I fly a Subaru, the jury is out on whether the per hour costs from acquisition, fuel use and repair/ overhaul costs compare favorably with the tried and true Lycoming. If I can get 500 hours between overhauls it looks like it would save only about $3000 total over 2000 hours- probably not worth the trouble over the Lycoming. Some of us are slow to learn...
I know you make your living being good at SI technology, so I'm not going to convince you of anything. But I will say that I'm very happy with the performance and economy of my Diesel RV9. I have enjoyed the challenge of developing the FWF installation.
Just curious - in what way are you expecting the SI engine to be inferior in this long climb? Are you expecting that the engine can not tolerate long duration, high power operation and will overheat? If it overheats, is that a fault of the engine type (SI vs CI), or of the cooling system design?As far as your bet goes, you're on!! If you can find a stock turbocharged 400 inch SI pickup, bring it on down and we'll pull the Baker grade together on a hot day, with 10,000 lbs in tow. I make a decent salary and I'll gladly put it up. Sure, you'll out-accelerate me for the first few miles, but I'm not worried about that.
IA good friend of mine has a Egg H6 in his RV7A. He's flying off his phase I now, so I haven't flown in it yet, but it sure is quiet and smooth at low RPM's. I can barely hear him as he taxis by my hangar.
Certainly no diesel can match the specific output of the turbo era F1 cars (1000hp/L) or even approach a fraction of the 6500+hp and 4500+ lb/ft. that Top Fuel engines produce these days on a cubic inch basis or in ETs or trap speeds.
Its a shame the US has taxed diesel so heavily. I run the non-taxed fuel in my RV, which saves me $.50/gal.
I know you make your living being good at SI technology, so I'm not going to convince you of anything. But I will say that I'm very happy with the performance and economy of my Diesel RV9. I have enjoyed the challenge of developing the FWF installation.
Kurt
Just curious - in what way are you expecting the SI engine to be inferior in this long climb? Are you expecting that the engine can not tolerate long duration, high power operation and will overheat? If it overheats, is that a fault of the engine type (SI vs CI), or of the cooling system design?
I haven't read the rest of your post yet, but i'm really surprised you'd use a top fuel anything as support for di si engine compared to a diesel in airplane use.
isn't top fuel a 90% nitromethane/ 10 % methanol? that is no way a fair comparison to anything in the mogas vs. diesel discussion this thread seems to have focused on lately. At least some of the other technology used in the diesel/ mogas car conversions are usable in an airplane, but i don't see funny gas ever getting in one for anything but race use
The point I'm trying to make here is simply to dispel this false torque myth perpetuated about diesel engines and "pulling power". Hp does the work, not torque in all motive applications whether it is truck pulling a trailer or in an airplane. Within the effective rev range, area under the hp curve defines an engines ability to perform work. Since the SI engine is a much higher speed device and gasolines and alcohols perform better at high piston speeds, there is no contest in this regard. SI engines generate higher hp on a per displacement and per manifold pressure basis than CI engines period.
Running only 5.5 psi boost, I have stomped on a full on Gale Banks 6.6L turbo diesel truck. The driver was extremely unhappy judging from his facial expression! He was under the false impression that 800lb/ft was going to flatten my "Rice Rocket". I couldn't resist rolling down my window at the third stoplight (yes, he had to try it three times to make sure he wasn't seeing things) , pointing and laughing. Immature perhaps but very satisfying.
I don't get it at all. Isn't the 240 a car?
my diesel truck weighs about 7500 lbs. whats the 240 weigh?
anyhow, back to the diesel topic, you present a good argument, but one thing i'm wondering, every semi, cement mixer (your example) big rig and most 250/ 350/ 450 sized trucks that are for pulling use all use diesels. why is that if the gas engine is superior?
I will dispute it every time I see this nonsense about how "torquey" turbo diesels are compared to atmo SI engines however. Of course any turbocharged engine of a given displacement will produce more torque than a similarly sized atmo engine whether CI or SI. That is a no brainer.
Hey Kurt, i was wondering, you use off road diesel (non road taxed?) Is your mix the higher sulfur diesel, and does your engine run better with it?
I run the standard off-road diesel with red dye. Here in So. Nevada, it is the same as clear auto diesel, ultra low sulfur, but without the tax. According the the factory and other sources, the diesel produces about 5% more hp than JetA, so I have to bring the throttle back just a little on takeoff to make sure that i don't exceed max rated hp.
WAM has encouraged me not to run red fuel in my plane because in the UK, red fuel is for farm use and is of substandard quality. I have checked with my supplier and have been assured that it comes from exactly the same source as the clear on-road fuel, with dye added before it is delivered to me. Does anyone out there (here in the US) have any different experience that this? I would hate to run inferior fuel just to save $.50/gal. I have a large filter on my supply tank, which I change and inspect regularly. So far, I have found no contamination in the fuel.
I have not put Jet A in the tanks yet. I just can't bring myself to pay the $4.00/gal they want here at 61B. I will, however, break down soon and fill one tank just to see how it compares with diesel.
Kurt
I run the standard off-road diesel with red dye. Here in So. Nevada, it is the same as clear auto diesel, ultra low sulfur, but without the tax. According the the factory and other sources, the diesel produces about 5% more hp than JetA, so I have to bring the throttle back just a little on takeoff to make sure that i don't exceed max rated hp.
WAM has encouraged me not to run red fuel in my plane because in the UK, red fuel is for farm use and is of substandard quality. I have checked with my supplier and have been assured that it comes from exactly the same source as the clear on-road fuel, with dye added before it is delivered to me. Does anyone out there (here in the US) have any different experience that this? I would hate to run inferior fuel just to save $.50/gal. I have a large filter on my supply tank, which I change and inspect regularly. So far, I have found no contamination in the fuel.
I have not put Jet A in the tanks yet. I just can't bring myself to pay the $4.00/gal they want here at 61B. I will, however, break down soon and fill one tank just to see how it compares with diesel.
Kurt
You guys are all waving the wrong numbers about. BMEP, torque, boost pressure etc. are all pretty irrelevant for aircraft. The two important characteristics (not just numbers!) are BSFC and power/weight ratio, or if you want to combine them both, power/mission weight
Diesels will leave an SI engine for dead in BSFC terms. An SI engine running lean might come quite close at one point, but nowhere near over the whole BSFC map.
Weight is the diesel problem, but this can be mitigated to a large extent with clever specification and design. Diesels will be very competitive in power/weight ratio terms at some point and they will blow unleaded engines into the weeds on a power/mission weight basis too.
A
The Thielert was a 4-stroke high revving valved engine. The DH/WAM are both slower revving relatively simple 2-stroke designs. I'll suggest that high RPMs are a major the detriment to durability. True in any engine, but more readily apparent in one utilizing high cylinder pressures. After all, a top-fuel engine has a TBO of 0.05 hours and a typical automotive race engine, I think, is 3 hours.
Restating things another way without the numbers in front of me, I'll bet that a Thielert piston has to travel 50-100% further at a correspondingly higher speed to obtain the same amount of power as a DH or WAM. I'd bet, without knowing, that the durability of automotive diesels suffers for the same comparative reason. Looking at it this way, no wonder why Thielert had to wrestle with oil consumption.
I'd dispute this as well Andy. Published specs for BSFC for the Thielert aero diesel were only about 6-10% better than what we see today on something like an IO-550 running LOP.
An RV9 with an O-235 burns about 4.5-5 gal/hr vs. 4 for the WAM at the same speeds- not much difference.
The IO-550 is a pretty impressive engine when it comes to BSFC, but it relies on 100LL. When 92UL or whatever it will be comes along, then what? Also 6-10% is best case (and still worth having) When you move away from that "best" point, you'll find the margin increases - quite dramatically at full power! I will agree that the Thielert does bad things to the diesel's image in most other respects though. It's not the way you'd do it if you had a second chance, is it? (Oh, wait a minute - what's going on over in Austria? Doh!)
Yes, 10-20% reduction in fuel burn isn't that impressive, is it? Bear in mind that the WAM is a pretty inefficient being an IDI diesel. As a DI, you could probably remove another ~10%