Al Marsh

Will no-lead avgas cost $10 a gallon?

August 17, 2010 by Alton K. Marsh, Senior Editor, AOPA Pilot

I debated awhile before posting this due to an obvious conflict of interest between the author of DieselAir newsletter who just wrote about the future of avgas, and his past consulting work. Andre R. Teissier-duCros was a consultant to an Atlanta company called DieselAir Aircraft formed to equip Cessna 182 aircraft with the SMA line of diesel engines, but the company no longer exists, according to former CEO Leonard Harris. Teissier-duCros is also publisher of the DieselAir newsletter. That said, I checked his background and decided his expertise is worth considering. The bottom line of his survey is this: a lead-free, ethanol-free alternative to 100LL will be available in five to eight years, but it will cost $10 a gallon. That price, the prediction goes, dramatically reduces the general aviation fleet. Manufacturers will begin equipping piston-engine aircraft with diesel engines–especially for fleet sales to flight schools. Many aircraft owners will switch to mogas, and the light sport aircraft equipped with Rotax engines actually prefer mogas. Those that can afford the $10-per-gallon price will continue to fly with the more expensive but environmentally friendly fuel, but will eventually convert to diesel engines when one is available for their make and model. Is that the truth, or a dream found in a PowerPoint presentation on the floor of the SMA board room? Teissier-duCros says it comes from his worldwide survey of opinion.

43 Responses to “Will no-lead avgas cost $10 a gallon?”

  1. Alex Kovnat Says:

    Avgas need not cost $10 a gallon. If, that is, aviation piston engines and fuel systems are rebuilt or re-designed to withstand ethanol. One notes btw, that according to an on-line newsletter available to EAA members, as early as 1935 there were warnings about “alcoholized gasoline” and its harmful effects on airplanes. But if aircraft fuel systems and engines are re-designed to deal with ethanol’s solvent effects on certain polymers and corrosive effects on unprotected aluminum, the problem can be reduced to managable proportions.

  2. Andre Teissier-duCros Says:

    Alex, what you say is perfectly sound. Of course we could redesign aero engines to fit an ethanol addition to fuel. This means a whole new generation of engines to develop, test, certify. It means an STC for all airplane models presently in production, all this constituting a tiny market for a future lead free methanol loaded Avgas which will sell only in the US. Meanwhile the rest of aviation world has already begun the shift to diesel and away from Avgas. Continental has already decided that long term belongs to diesel. Also, if US. DOD does succeed in having one single fuel for all engines on military aircraft and vehicles, do you think that single fuel will be a new kind of gasoline, or simply jetfuel (partial bio-jetfuel later) already available everywhere and fueling all the big Lockheed-Grumman-Boeing toys?
    Also keep in mind that this whole effort for a lead free Avgas addresses needs of a piston-engine fleet getting older and older and flying less and less, see on this AOPA figures.
    AOPA 01314249

  3. Mark Hubelbank Says:

    If we give them a chance and the FAA does not impose impossible barriers, I expect Swift fuels will demonstrate a product at well below $10 but above what we have now. It will probably solve 99% of the problem and require some slight modification in the way we handle fuels but I expect it will be something we can live with while jet fuel capable engines slowly (20-30 years?) replace the current stock.

  4. mike elliott Says:

    If the piston engine fleet is getting older and older, and flying less and less (which I believe, but not because of Avgas issues, but because of political, legal and the resultant economic forces), then why is it such a big deal to the EPA? This self fulfilling phrophesy of the death of piston GA should placate the insatiable appetite to “govern”. Who in their right mind would spend the $$ to retrofit an existing commander or mooney with a desiel at a cost greater than the airframe value? Hence the motivation for the manufactures to promote high prices for 100 no lead solution. We have met the enemy and it is us, and our greed glands.

  5. Carl Sbarounis Says:

    It just makes me sick that AOPA is caving in to getting rid of 100LL Avgas. Fight for our fuel. There is so little Avgas being used compared to other fuels. What about other 3rd world countries? Are they going to use this new fuel? AOPA, please fight to keep Avgas.

  6. Stuart Spindel Says:

    Back in the fifties, almost all automobiles ran on leaded gasoline. All DC3, 4, 6 and 7, Constellations, Martin 404, Convairs, KC97 etc, as well as all General Aviation aircraft also used leaded gasoline. Do we have the change in atmospheric concentration of lead in ppm compared with current levels? At some point, there must be an acceptable level that is not Zero.

  7. Will Alibrandi Says:

    Considering that annual 100LL use in the US represents one tenth of one percent of all motor fuels, the concern over lead in avgas strikes me as a witch hunt by the EPA. That said, I see the benefits of unleaded avgas as being more friendly to engines, as long as it’s available without ethanol. There’s no reason 100UL should cost anywhere near $10, even considering the boutique nature of the fuel. By removing the lead, it can be run through pipelines with other unleaded motor fuels (assuming no ethanol content), and does not have to be segregated like 100LL is now. By eliminating the need to truck the fuel in separately, the transport costs should be significantly reduced, which should mean lower wholesale and retail prices. I think GAMI’s G100UL holds the most promise right now as a true 100 octane replacement, and am curious to see what develops.
    I like the idea of diesel aviation engines, but the buy-in cost is prohibitive. I think Continental is hedging its bets by diversifying its product line. Until a major OEM offers diesels on their aircraft I doubt many owners will pay to hang diesels on their airplanes. A much cheaper alternative would be retrofitting water-cooled cylinders to current aircraft engines, which would eliminate many disadvantages of air-cooling and would allow a lower octane fuel to be used, permitting more of the fleet to operate on high octane mogas. The economics will dictate what is the most cost-effective solution.

  8. Jim Cavanagh Says:

    First, lets get 91 MON UL auto fuel into our airplanes. It is imperative that we get the states to require a listing of ANY ethanol added to the blend. This was purely a reaction to local farmers and throwing them a bone, anyway). By allowing ethanol in fuel without documenting it at the pumps has obviated all of the STC’s previously sold. This simple legislative change would cut the cost of our present flying by t two thirds and get people into the air, get money flow moving, and sell parts and services.

    Next, we need STC’s for the use of the fuel, or at least a testing program to determine the usefulness or the plumbing needs (I.E. pushing rather than pulling fuel pumps) for low wing aircraft. EAA is pushing for this in order to sell more STC’s. Would a test period and Field Approval be possible for individual aircraft?

    Regarding Swift Fuel. Alcohol kills fuel bladders, Ask FFC. Have they done any testing in this area.

    Then we need 94UL immediately approved and distributed. This is 100LL without the Lead. 80% of the planes out there can use it 100 percent of the time, and the other 20 % will have to run richer, at less power, or install FADEC.

    Finally, get humping on Diesel engines if for no other reason than the more than double amount of fuel that can be refined per barrel of oil.

    Tessier -duCros knows his stuff. His newsletter is a compilation of his opinions, rather than empiracle data, but the data is in his head.

  9. Tom Porterfield Says:

    Lead is a God given natural component of and in the earth. We can never rid the earth of lead. Removing lead from avgas is as stupid and asinine as California hunting laws, where you can no longer use a lead bullet to shoot a deer. Because the enviromentalist think if you shoot a deer with a lead bullet and the deer gets away and dies in the forest, an endangered Condor will swoop down from the mountains and devour the carcass of the deer. In the process it will digest the lead bullet and go back to the mountains and die of lead poisioning. The enviromentalist don’t mention the those very mountains where the Condor lives is loaded with lead deposits.

    Why do we have to bend under political pressures so some enviromentalist can validate his job, when the scientifical data shows otherwise. Just like Al Gore’s rantings on the enviroment have been proven to be untruthful. While Al Gore lives in a house that wastes more energies and spills more polutants into the air than most small companies.

  10. Andre Teissier-duCros Says:

    What DieselAir published is not an opinion, but a tentative forecast regarding what will probably happen, not what will happen for sure, nor what should happen. EPA may very well decide to prolong 100LL for political reasons, or to stick to its guns for other political reasons. In that latter case, we might see the US sticking to leaded gasoline while the rest of the world shifts to diesel. Such is already the case for diesel automobiles, also for high taxation on automobile fuels in general ($7-8/gallon in Europe and many countries now). But the difference here is that the market of 100LL, compared to all markets of petroleum-derived fuels, is tiny; and the planes using it are old and flying less and less anyway.
    A few certainties:
    AOPA, FAA, EPA, GAMA and the whole US industry are doing a good job weathering this delicate issue, and generally need support, not suspicions about any foul game going on.
    It is nobody’s fault if we are stuck in the US with excellent engines and an excellent fuel which were both born around WW2 and are now both obsolete.
    The piston-engined aircraft represent more and more a professional market, and professionals fly much more hours per year. They will like fuel efficiency, more safety, more useful load, and a reasonable operating cost per hour. Avgas priced around twice the price of automobile fuel had indeed provided that for decades, witness the Alaskan experience: Alaska has had for decades the highest density of piston engined planes per capita.
    A real question: Can any kind of rejuvenated Avgas, with very low lead or no lead at all, bring a solution that will not impose a very slow and costly cycle of engine developments, testing, certifications, and aircraft STCs, and therefore come out with a fuel price that can compare to what we had ten-twenty years ago? Our forecast says: perhaps a syngas as described might be the least costly solution, that’s all.

  11. Peter Rohl Says:

    The question is ill-posed. AvGas (100LL) already costs more than $10/Gal in parts of the world today. Even automotive gasoline may very well cost more then $10/Gal in the US 8-10 years from now. The question should be what the price differential will be between a 100LL-replacement fuel and unleaded automotive gasoline/diesel fuel, which currently in the US is somewhere between $1.50 and $2.50. The higher the price differential is, the more attractive diesel engines will be.
    Besides, rants against “the environmentalists” are not helpful. Leaded AvGas is going away. If not for environmental reasons, then for economic reasons. The market for leaded AvGas is getting smaller and smaller, only one manufacturer for TEL (the lead additive) is left in the Western World, and at some point, somebody on the critical path in the supply chain will make the decision that there is no longer a business case for supplying leaded AvGas.

  12. Tracy Smith Says:


    I’ve been reading your newsletter for quite a while now and I believe absolutely you’re on the right track. Much of the future of General Aviation – the LSA market – comes to us from overseas…and yes I am including the 162 SkyCatcher in that group as well.

    I’m a big believer in the compression-ignition engine for aero use….but with a few more early-adopters the aerodiesel will move forward. I see the tipping point with Cessna offering a 100hp aerodiesel in the 162 for the worldwide market and seeing those airframes coming back into the US as a grey market airplane. Yes, I know Cessna wanted to go with Thielert, but that was a bad idea anyway; the engine just wasn’t ready. The SMA engine just doesn’t have enough traction (yet) to be viable USA powerplant.

    Will Continental leapfrog to the front of the technology parade? Maybe the Gemini 100? DeltaHawk?

  13. Mark C Says:

    I think Jet-A powered diesel engines are the future of piston aviation. The diesel engine is well suited to prolonged operation at a steady RPM and high torque output, and the reliability and longevity of diesel engines will, in the long run, be a benefit to pilots and aircraft owners. If I were an aircraft manufacturer, I’d be giving this a serious look. The major obstacle to this progress is cost, and the cost is driven primarily by regulation. If the government is that concerned about environment damage from 100LL, they need to get out of the way of progress. When it takes 10 years and 100 million dollars to certify EACH aircraft/powerplant combination, it’s not possible to make the switch, as there is a very limited market for 5 million dollar 4-seat piston aircraft. The same applies to the possibility of retro-fitting older aircraft, no one is going to put a $100K+ engine into a $45K Cessna 172, and that same owner isn’t going to scrap his airplane to buy a million-dollar replacement, because it’s not within his means.

  14. Mickey Fluger Says:

    Reality for me, is that mogas has been one-half to two-thirds the cost of avgas, so, I burn mogas, and have been for 20 years.
    Sadly, the composition has been 10% ethanol to currently 5% ethanol, as available at California pumps. Better days were when they had methyl tertiary butyl ether as the anti- knock.I have an 80 octane engine. No problems whatsoever, no lead sludge in my crankshaft nor crankcase, no lead- fouling, no lead salts. Maybe make 70% of the fleet eligible for mogas?

  15. Greg Goodknight Says:

    “What DieselAir published is not an opinion, but a tentative forecast regarding what will probably happen, not what will happen for sure, nor what should happen.”

    It’s a self serving guess from folks who have a vested interest in pushing diesels. Without a good scare, the sheep just can’t get motivated to allow high octane gasoline fuels be discontinued. $10 is scary, but the two leaders in 100 octane unleaded avgas developments have both stated they expected prices of their product to be on par with 100LL costs.

    For the record, I’d be perfectly happy for my ’60′s Bonanza to have an efficient Diesel engine, but it ain’t going to happen this decade

    I’ve taken my AOPA membership OFF automatic renewal, and won’t be renewing unless and until the AOPA disavows any support for the 94UL coalition, and throws its weight behind a drop in 100LL replacement that is either 100 octane or as close as is technically possible, a fuel that would allow the folks who use 70% of the current avgas supply who *need* high octane ratings to put fuel in their plane and fly.

  16. Larry Gettleman Says:

    Diesel engines are superior to gasoline engines in propeller-driven aircraft because:

    1. Diesel engines run on jet fuel (or almost anything else) and are 30% more efficient;

    2. The energy content of diesel fuel is higher than gasoline, which offsets the increased cost of diesel fuel today (2010). Alcohol and similar oxygen-containing additives reduce the energy content of gasoline even more;

    3. Diesel or jet fuel is a lubricant whereas gasoline is a solvent. This affects lubrication, especially at startup;

    4. Diesel engines run more efficiently at slow speeds and so do propellers. Gasoline engines run more efficiently at high speeds; some high-performance engines use reduction gears;

    5. It is more appropriate to measure propeller performance in terms of torque (newton-meters or pound-force-feet) rather than horsepower (watts or joule-seconds). A smaller diesel engine with increased torque will perform the same as a larger displacement gasoline engine with increased horsepower that is generated at high revolutions. This affects the size, weight, and starter motor requirements of a diesel engine;

    6. There is no need for an ignition system (dual magnetos, high-voltage wiring harness, dual spark plugs) which reduces maintenance. Once started, diesels will run continuously as long as they have fuel and air to burn and a place to exhaust the products of combustion;

    7. Diesels all use fuel injection and are less sensitive to changes in altitude;

    8. Modern electronic management of diesel engines are sophisticated and use one single control; and

    9. Oil change intervals and overhaul times should be much longer than comparable gasoline engines because they are built to closer tolerances and other reasons mentioned above.

    What are we waiting for?

  17. Greg Goodknight Says:

    “What are we waiting for?”

    Working, reliable and practical diesels in operational aircraft is probably the single biggest thing we’re waiting for. Kill off the current workhorses in the GA piston fleet by killing off the big Continentals and Lycomings fuel supply won’t drive them to diesels, it will just drive GA into a big smoking hole in the ground.

  18. Charles Churchman, P.E. Says:

    I have good news, guys. The technical problems are solved as far as a drop in replacement for 100LL is concerned. The problem is a “green” one, and I’m not talking environmentally.

    Swift’s 100SF is a true drop in replacement for 100LL, and also provides lower fuel consumption of about 10% based on the FAA Test Center tests. You can run about 2″ more manifold pressure without detonation – the octane is higher than 100LL. Another way to look at it is your range is extended by about 10% on the same number of gallons. It can be made from feedstocks which are much less expensive than the crude oil 100LL is produced from. So there is potential for it to cost LESS than current avgas. Not going to happen with diesel………..

    The only problem right now is getting the money to build the plants. It costs roughly $ 5-10 an annual gallon to build a biomass fueled production facility, which means to make 200 MM gallons a year is going to cost $ 1-2 billion. This can be amortized over 20 years, but somebody is going to have to come up with the money. Know anyone with 1-2 billion laying around not being used? Swift is selling stock………………

  19. Norman Davis Says:

    Gee 10 bucks a gallon. Some one’s gonna get wealthy while we get soaked. I’ve been using 97 UL in my Cessna 120 for 6 months and I don’t notice any problems. What’s wrong with promoting that, or is that just too simple to do?

    I’m at the pont now where I’m quite disgusted listening to the industry whine about no lead for these antiquated engines we have to use and no one seems to have the guts to redesign for unleaded fuel use. A lot of wrong and goofball thinking out there. Maybe U.S. manufacturers should move over and let someone else do the work. I’m sure the Pacific Rim nations are up to the task.

  20. George W. Braly Says:

    Regardless of all of the comments on this subject, the following remains true:

    Twice this week, I have gone flying in a 550 c.i. 8.5:1 compression ratio piston powered, air cooled Cirrus aircraft with a turbo supercharger set up to 34.5″ Hg MAP, so the engine was producing approximately 350 Bhp.

    The fuel for those trips was unleaded avgas. The cost of that fuel was substantially less than $10/gallon. In fact, it was around $6/gallon, made in small quantities.

    Those are facts.

    One avoids embarrasment by restraining themselves from telling someone they cannot do something the person is already doing.

    Regards, George

  21. Stephen Phoenix Says:

    I wonder why so many people seem to think that the FAA, AOPA, EAA etc should “do something”. Do what? In the end it will be the entrepreneurs that determine the outcome. If GAMI or Swift fuels or diesel makers or turbine builders or even electric airplane inventors can find a way to bring a solution to market and make some money, that solution will define the future. No amount of lobbying, protesting or letter writing campaigns will alter the basic market/evolution process. At least not in the known universe.

  22. Andre Teissier-duCros Says:

    I answer here to Tracy Smith and Greg Goodknight.
    Tracy: Thanks for your support.
    Now, if Cessna was announcing to the world that the Skycatcher is going to be marketed with an OEM 100-140HP diesel engine, it would be a bomb. It would become at once the basic economical trainer of the future, the best LSA, for IFR pilots a true minimal cross country IFR machine, for Alaskans a reborn Super cub, and for Latin-American, ANZ and European pilots a once-again affordable plane. It would at same time tell to a world in which one quarter of flying machines are Cessna singles that Cessna, therefore the world of piston-engined airplanes, is going diesel.
    Greg: I agree that one never accomplishes anything by killing something; and a lead free Avgas would help the industry at least as a transition. I created DieselAir in 2001 because I had been thinking for many years that diesel is the future for piston-engined aircraft. I still think so. I have no investments in the aero diesel industry.
    To all: My apologies for $10/gallon Avgas. I should have added: in 2010 dollars, on the US market. Right now in Africa Avgas is $16-20/gallon… if you can find it and if you re-filter it yourself.

  23. John Schilling Says:

    100LL is going away, period, and it’s going away no matter what AOPA wants or does. Never mind the EPA; there’s only one company left that makes the tetraethyl lead part, and nobody is stupid enough to replace them. And in the long run, yes, heavy-fuel engines (a mix of turbine and diesel, all burning Jet-A or the like) will replace them. Twenty or thirty years from now.

    But an intermediate stage where anyone is selling 100-unleaded at $10/gallon, that’s not plausible. Who would be buying the stuff? 91/96 and 94UL can be delivered at a retail price of $4-$5/gallon, and will serve most of the market. Granted, with conversion costs than might range from a few $100 for STC paperwork to a few $10K for new FADECs, but far cheaper than paying $10/gal for avgas. And most of the users who absolutely can’t use 94UL, are commercial operations that can’t make a profit at $10/gal – their low end competition will be paying $5/gal for 94UL, the high end $4/gal for Jet-A. That doesn’t leave many people who will taxi up to the $10/gal 100UL pumps, if there’s an FBO in a
    50-mile radius who’s selling 94UL. Probably not enough to pay for the development of 100UL.

    Most of us would prefer to see 100UL at the pumps at no more than $5/gal by the time 100LL goes away. But if that doesn’t happen, I’m pretty sure those pumps will then be filled with $5/gal 94UL rather than $10/gal 100UL. Or maybe some of each at the start, with the 100UL providers changing plans in a hurry.

  24. Andre Teissier-duCros Says:

    To John Schilling:
    What I understood is that the 30% of airplanes who consume 70% of Avgas are modern (Cirrus, Piper PA46, Corvalis…) or recent (Turbo Skylane, Turbo Stationair, Mooney, Bonanza, Baron…) and supercharged; are worth money; and have engines flying lean of peak, therefore hot. They cannot fly with 91/96 or 94UL. They cannot fly with alcohol in their fuel (corrosion). They could fly with a synfuel as outlined in our forecast. Maybe the Swift can be that fuel, I don’t know enough yet.
    But whether mineral or bio synfuel, I say it will be costly to manufacture because synthesis and fermentation both consume energy; because the process is a complex one (more steps, therefore more capital investments); because retail distribution must remain dedicated to Avgas; and because ultimately it is a small market. That’s why our forecast expects that the extra costs in manufacturing, distributing, and retailing a no-lead 100 Octane Avgas will push the retail price some $3 to 5 more than 100LL in 2010 dollars. But I welcome any fact or data which allows us to be more accurate: Right now we are not.

  25. Kelly McMullen Says:

    So many misperceptions. Diesel will have substantial issues in places like Alaska unless the supply is the more expensive Jet A with pour point depressants. Flying LOP is NOT hotter than ROP, it is in fact COOLER than ROP operations. There are a LOT of normally aspirated engines such as 200 hp Lycomings and 300 hp Lycomings and the higher compression Continentals that dominate the market in Mooneys, Pipers, Beeches and Cessnas that will NOT operate with 94UL without substantial modification and recertification with reduced gross weights, destroying the value of said aircraft. That is why virtually all of the non-training fleet need 100 octane fuel. Both GAMI and Swift have given substantial indications that they can produce their product for less the 50% above the current avgas pricing, and with volume production efficiencies are likely to cut that premium to 10-20%.
    All this talk about $10 a gallon is simply inaccurate and counter productive, by folks that have an agenda to sell other power plants, IMHO.

  26. Al DeMarzo Says:

    I’d sure be interested to hear a reply to George from Andre. Or have I wasted my time reading this blog?

  27. George W. Braly Says:

    Al, try this:

    George W. Braly Says:

    August 20th, 2010 at 8:54 pm
    Regardless of all of the comments on this subject, the following remains true:

    Twice this week, I have gone flying in a 550 c.i. 8.5:1 compression ratio piston powered, air cooled Cirrus aircraft with a turbo supercharger set up to 34.5″ Hg MAP, so the engine was producing approximately 350 Bhp.

    The fuel for those trips was unleaded avgas. The cost of that fuel was substantially less than $10/gallon. In fact, it was around $6/gallon, made in small quantities.

    Those are facts.

    One avoids embarrassment by restraining themselves from telling someone they cannot do something the person is already doing.

    Regards, George

  28. Andre Teissier-duCros Says:

    Al deMarzo, here you are, thanks!
    Kelly: Sorry for the Hot/Cold LOP/ROP unclear statement. What Lycoming and Continental told me is: said engines will corrode fast with any alcohol in fuel, and do need 100 Octane. So at the end of the day we agree but I stand corrected.
    Future price of GAMI and Swift fuels: yes, they will be affordable, that’s what they say. Frankly I am very skeptical because the cost figures do not add up right. They don’t show with what ingredients, costing how much, through which processes exactly, costing how much in capital costs, and with how much other induced costs (energy, maintenance, storage) they will produce their fuel; and we don’t have a validation from a leading Avgas brand distributor confirming such figures. So our team is doing its own speculation. And we say: It will cost more, for reasons I already wrote above. If I am wrong or misinformed, I apologize in advance and suggest that someone provides the missing info. I will publish it with permissions.
    Att. George Braly: You say: “The fuel for these trips was unleaded avgas, costing around $6/gallon made in small quantities.” Can you explain which “unleaded Avgas” you mean? Thanks in advance.
    To all: I believe I am courteous in this exchange, which I follow in good will. May I suggest that, for such a difficult, sensitive and tricky subject, we all abstain from derogatory remarks regarding competence, motive questioning, interest conflicts, ethics questioning, vested interests, etc.? Some of the facts, ideas and concepts exposed right here thanks to AOPA are most interesting and useful. Exposing them in a courteous context would also make it fully enjoyable.

  29. George W. Braly Says:

    Andre Teissier-duCros states:

    >>Att. George Braly: You say: “The fuel for these trips was unleaded avgas, costing around $6/gallon made in small quantities.” Can you explain which “unleaded Avgas” you mean? Thanks in advance.<<

    Which Avgas ? Yes. G100UL. We routinely fly a high performance, high compression, turbo-supercharged TCM 550 c.i. engine on G100UL.

    By my last count, some 14 different pilots, including people like Paul Bertorelli from Aviation Consumer and Alan Klapmeier (founder of Cirrus), Dave Hirschman (AOPA) and a number of others have flown the fuel in the airplane. These are normally considered serious people.

    They have all see the aircraft operate on the G100UL and seen the full page engine display when the fuel is switched from right tank (G100UL) to left tank (100LL) – - and they easily appreciate that the fuel is a nominal drop in replacement for 100LL. They have each done this with the manifold pressure increased to a point to where the 310 Hp engine was making around 350 BHp – - with the same nominal results.

    Again – - one normally avoids embarrassment by not asserting that people cannot do things that they are already doing and have been doing for over six months in public with more than a dozen unbiased witnesses to verify the functionality of the fuel.

    You too – - are invited to come to Ada, and spend time with us and observe the fuel both on the test stand and in the aircraft.

    Frankly, at the present time, about the only two well recognized entities in general aviation that have not done that are the EAA and the FAA.

    Regards, George

  30. Andre Teissier-duCros Says:

    George, my apologies, I didn’t realize that when you meant a lead free Avgas you meant GAMI’s G100UL. G100UL, if I got it right, is a petroleum derived fuel without alcohol nor metallo-organics, therefore fits in the forecast our team has executed.
    Now,DieselAir’s forecast never said people CANNOT do it. Quite the contrary: We said it will probably be on the market as a fully certified fuel, distributed by at least one nominal fuel brand, by 2015 or around. Applied to GAMI, it means that by the time G100UL is certified and in full production, we expect that 5 years will pass by (and some more money will be spent that also needs to be amortized) and the full production cost will be such that the final price on the field, taking into account the small market size and the distribution costs, will be some $3 to 5 more than a 2010 price of $6 for 100LL. But if GAMI will supply me with a cost and price analysis of their fuel once certified and ready to sell, showing more encouraging figures, again I am ready to publish them.
    If I read you right, FAA hasn’t yet started evaluating G100UL. I cannot imagine such a critical certification lasting less than a few years.
    And thank you again for a positive information.
    Best regards,

  31. George W. Braly Says:

    >> But if GAMI will supply me with a cost and price analysis of their fuel once certified and ready to sell, showing more encouraging figures, again I am ready to publish them.<The fuel for those trips was unleaded avgas. The cost of that fuel was substantially less than $10/gallon. In fact, it was around $6/gallon, made in small quantities. >If I read you right, FAA hasn’t yet started evaluating G100UL. I cannot imagine such a critical certification lasting less than a few years.<<

    There are several problems with that statement.

    First, it is not, technically, the FAA's job to "evaluate" the fuel. The FAA's job is to certifiy engines and airframes that are specified by the type certificate holder to operate on a fuel that meets a defined specification. It is common to refer to the fuel as "FAA certified" or some similar phrase, but that is not accurate.

    Second, more challenging fuel qualification efforts, in the past, have been done in a matter of months, not years;

    Third, the G100UL is sufficiently close in composition to conventinal petroleum gasolines that the fuel qualification effort ought to be reasonable. But I acknowledge the difficulties with this sort of effort that tend to come up in this area.

    And you are correct in pointing out that almost all of the interested Alphabet groups and airframe /engine people have conducted a serious and detailed on-site investigation – - and conspicuously absent from that list are the two entities I mentioned. I hope that gets remedied in the next 30 days.

    But it remains true that there is at least one cost effective aviation gasoline that performs on critical high compression turbocharged engines as well as grade 100LL and it has been flying around all over the United States for the last seven months . . . and counting.

    Regards, George

  32. Leonard R. Harris Says:

    I am still very excited about SMA and the future of diesel airplane engines. The reason I closed the Dieselair Aircraft Conversions company has everything to do with my health. I am a loser to osteoarthritis in both knees and hips . I recently underwent a total knee replacement on my right knee and am facing the left knee replacement soon. I have known Andre’ for 15 years and find him to be both intelligent and a reasonable person. As my health problems abate I will rejoin the hunt. I enjoy the Blog.

  33. Andre Teissier-duCros Says:

    I think George Braly has very well clarified the issue. GAMI hopes to get G100UL on the market in less, may be much less than 5 years. G100UL seems to be a true 100 Octane lead-free alcohol-free gasoline, and therefore constitutes a breakthrough. To my best knowledge this fuel is the one which has the most serious hopes to be the first operational lead-free Avgas. The remaining questions are: If its cost is around $6 in 2010, what will be its final retail price including margins and various amortization & depreciation charges, and when will it be available at any airfield for your Cirrus, Mirage or other. Then the Invisible Hand of the Free Market will decide…

  34. George W. Braly Says:


    You write:
    >>The remaining questions are: If its cost is around $6 in 2010, what will be its final retail price including margins and various amortization & depreciation charges, and when will it be available at any airfield for your Cirrus, Mirage or other. Then the Invisible Hand of the Free Market will decide…<<

    You should not seize on the $6.00 /gal number I quoted as a starting point for the price to "go up". Rather, you should, based on what I wrote, seize on the $6.00/gal number I mentioned as a starting point for the price to "go DOWN."

    Consider again, the very carefully chosen language that was used: "In fact, it was around $6/gallon, made in small quantities. "

    By that statement I had assumed that most readers would appreciate that the pricing point as quoted was not derived by using components that came in bulk quantities measured by dozens or many dozens of rail road tank cars. But, rather, it was made at that price from components that came by truck, in barrels, to a little town in southeastern Oklahoma.

    Regards, George

  35. Alex Kovnat Says:

    Andre (AOPA #01314249) asks:

    >>Also, if US. DOD does succeed in having one single fuel for all engines on military aircraft and vehicles, do you think that single fuel will be a new kind of gasoline, or simply jetfuel (partial bio-jetfuel later) already available everywhere and fueling all the big Lockheed-Grumman-Boeing toys?

    There is such a fuel, called JP-8. Its use is required for Army ground vehicles (which are nowadays all Diesel) as well as turbine-powered vehicles (nowadays only the M1 series Abrams main battle tank powered by an AGT-1500 gas turbine engine) and of course, helicopters (i.e. Blackhawk, Chinook, etc) which are turbine-powered. In combat theaters, JP-8 is also used for jet and turboprop aircraft.

    In general aviation, JP-8 could be used in Diesel engines or turboprop engines, if said engines are FAA-certified for said fuel. I don’t think JP-8 would be usable in spark-ignited aircraft engines.

    Mettatal Airport in Canton Township, Michigan, home of EAA Chapter 113, is not far from a railroad main line. I’ve been there numerous times for Chapter 113 pancake breakfasts. People I’ve met there agree its silly that those living near that airport complain about aircraft noise, but not about railroad trains which have to blow their air horns constantly to let everyone know they’re coming.

    Given the high cost of “botique” avgas, including both 100LL and the forthcoming 100 octane lead-free formulations, I have often wished a railroad track would be built, branching off the nearby main line, to enable railroad tank cars to be delivered to Mettatal Airport so as to reduce aviation fuel transportation costs. That might lower the cost of avgas at that particular airport to less than $10.00/gallon, or whatever price is forecast for the next few years. Of course one also has to consider the many other small airports which are part of our nation’s general aviation system.

  36. Andre Teissier-duCros Says:

    Alex, thanks for mentioning JP8. I agree that one cannot use it for existing spark ignition engines.
    Remark on the $6/gallon figure: In all our exchange we have indifferently talked of it as benchmark for either a COST or a PRICE. Our forecast exercise was talking of a retail PRICE therefore a comprehensive cost (ingredients, energy, shipment, storage…) and then a markup or margin on top. All private pilots know that 100LL is sold at a high margin, witness the high price differences one can observe from one airfield to another. By the time a lead free Avgas is marketed I expect the Avgas market to have shrunk, therefore the markup to have gone further up. Ex: You can still buy fluid for your Zippo lighter (I have one) because there are still a few smokers using a Zippo. Zippo fluid is a very light gasoline. It sells at $200/gallon , only you buy it in four-Oz containers.

  37. Alex Kovnat Says:

    Yesterday (Monday August 23) I started reading the September 2010 edition of Flying magazine. In this latest issue, one sees evidence of the possible phase-out of 100LL in the not to distant future. For example there’s an article on the Cirrus SR22T, whose engine has a lower compression ratio than what Cirrus previously would have used for such an aircraft. This results in somewhat higher specific fuel consumption. But the current SR22T also has increased detonation margin, which enables the owner-pilot to use 94UL fuel.

    A noteworthy example of how one owner-pilot is adapting to possible phase-out of 100LL: On pages 76 and 77 of said edition of Flying, we read about a guy who uses his Cessna Citation jet to fly clients to and from locations where advertisements are filmed. Here’s how he’s coping with the whole matter of decreasing 100LL availability, possibly having to settle for 94UL, the possible high cost of lead-free 100 octane gas, et cetera: The aircraft he flies just for fun, a Marchetti SF.260TP, is one of only seven privately owned SF.260′s that have been converted to TURBOPROP POWER!

    Expensive? Yes, but we’ll probably see more sportplanes of that kind in the foreseeable future.

  38. FRED LONG Says:

    This would be to low wing owners.
    Subject: fuel volitility
    As we all know, yet i have not seen it adressed in any of the letters thus far, avgas has a low volatility in order to not boil at high temperatures as well as lower atmospheric pressure or a combination of both.
    This boiling will cause what is known as vapor lock. Older cars that pulled the fuel from a gas tank low in the rear of the car to an engine driven fuel pump would sometimes vapor lock especially on a hot day at higher altitude. Pulling the fuel drew a partial vacuum and the heat lowered even further the boiling point; thus a vapor lock. I had a lot of experience with this growing up in the high desert country. This is the reason new car manufacturers solved this with electric fuel pumps in the fuel tank. Note this great breakthru was actually copied from older gasoline powered high flying aircraft.
    When my old cherokee 140 was built (1966) i guess everyone thought that avgas woulde be around forever.
    They have an engine driven fuel pump and on the firewall there is an electric pump pulling the fuel from each of the two wing tanks. In summary with a hot and high situation one could have vapor lock.
    I have researched the stc to burn mogas in my plane and the stc calls for the follwoing: if i have the standard pistons in the o-320 engine (150 hp) i only have to buy the stc and begin flying with mogas. If i have the higher compression pistons (160 hp), i must purchase from the stc holder, two electric fuel pumps each to be mounted near each wing tank and seperate new fuel piping as well as new electric controls to control each pump etc.
    This is due to the faa tests showing that the fuel vapor locked on the 160 hp version.
    Many car gas producers make winter blends of fuel and it finds its way into the summer market or into the hot areas of the country. So i bought a volatility meter in order to learn more.
    I am an api tank inspector in the tropics, and one of my functions is to inspect floating roof’s seals and note evaproative losses from large gasoline tanks. I have seen 150 ft dia steel floating roofs lifting up with vapor belching out intermittantly from under the liquid immersed rim seals.

    In summary the vapor pressure of a highly volitile fuel was doing this. My little volitility meter confirmed this.
    Next i went to most of the different brand gasoline stations and found an alarming number with volitile fuel.
    Next i took some of this volitile fuel, placed it in a can and set it near my airplane on the morning of a good hot day. By that afternoon measured temp. Was near 120f the volitility was unreal. The avgas in my wing tanks was 124f but the volitility was acceptable
    My concern now is that. How safe will i be if i totally trust the faa testing of the 150 hp 0-320. Buy the stc, then fill er up with mo gas, leave her sit in the good old hot tropical sun (directly overhead at noon now), take off and try to hop over a 9,000 ft cloud.
    With avgas i am able to do this routinely. If i were to switch to mo gas i would check very carefully the volitility.
    In summary to this i would say for the little engines like mine i would be happy with 91 or 100 ul – with proper volitility. As well to anyone planning to switch to mogas; buy a volitility meter and use it.

  39. Alex Kovnat Says:

    Fred, why are you shouting? The acoustics in this chat room are excellent. We can hear you without typing in all capital letters.

  40. Wayne Shaw Says:

    I have been reading comments and publications about Avgas and getting the lead out for quite a while now and am very curious why this is an issue. I retired from a major oil company and at least two seperate companies made and still make 100 octane and greater than 100 octane racing gas that doesn’t contain ethanol either. If no lead is added and no ethanol added it can safely transported through any pipeline and transportation costs are less so it is obvious that the unleaded gas can be made and the engines run better and cleaner than with lead additive.

  41. Will Alibrandi Says:

    Wayne, are you referring to Sunoco 260? There’s no guarantee that fuel could be certified under ASTM 910 and right now it’s retail price here is $9/gallon.

  42. John Ringel Says:

    I spent at least 45 minutes reading this blog. I come away with the following observations. 100 LL is but a very small percentage of fuels produced and used. The engines of aircraft needing 100LL to run properly should not be at the whim of environmentalist idea of their perfect world. 100 LL is a vast improvement in leaded fuels of he past. Obviously the EPA and some blowhard environmentalists want the world to change for the better, but is it really changing for the better? Just because 100LL has a small amount of lead, is it really unhealthy? Lead is a naturally ocurring element. Are we better off in 2012 versus say 1965? That answer is yes. I say leave 100LL alone. If these environmentalist want a cleaner fuel, make them pay of its developement. IMHO, we have a guy who would love nothing more than have the entire industry switch to diesel engines (no conflict there). Granted, jet A/ diesel is a viable alternative, but at what cost? I have an engine that requires 100LL to run properly. The engine has another 900 hours before TBO. When it comes time for TBO, I will consider a switch to diesel, but not right now. Don’t get me wrong on this. I am not against a change in 100LL as long as the alternative doesn’t cause a financial burden on those who have engines requiring 100LL.

  43. Mannstein Says:

    Has anyone considered butanol as an additive to mogas instead of ethanol? It has none of the problems of ethanol as well as having a higher heating value (more BTUs per gallon)

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