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Pelton: Finally, Some Plain Speaking

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Twenty years into what seems like a hopeless search for an avgas replacement, the only thing that appears to have emerged—other than reams of depressing reports—is fear and paralysis. So Cessna CEO Jack Pelton's unambiguous statement last week that yes, he has seen a replacement fuel, it appears to work and looks producible was a bracing blast of breathable air.

Pelton and AOPA President Craig Fuller visited General Aviation Modification Inc.'s modest test facility in Ada, Oklahoma and saw the company's proposed G100UL run through a detonation cycle and learned more about how the stuff might be made. Pelton urged other GA leaders to get busy and have a look. To date, even seven months into GAMI's project, GA principals are only now taking notice and getting for-the-record comments that say anything substantive gives the word futility a bad name. It baffles me that so many people are afraid to state honest opinions.

I noted that Pelton sent his comments a couple of hours after seeing the test run. He didn't wait for someone to craft a carefully worded press release. Why is this such a big deal? (And is a big deal.) Because finally someone has stepped up and said: Look, let's stop implying that just because we've failed so far, we can't figure this out. I did not interpret Pelton's comments as an endorsement for G100UL so much as an illumination of the conviction that there are innovative companies out there that can solve this problem if we'll just let them. (Hundred octane and all.)

With aircraft sales still in the tank, Pelton fully realizes that uncertainty about future fuel supplies is beginning to chill the market. And the longer we go without some expression of confidence and forward movement, the colder it's going to get.

What I am anxiously awaiting is to see if Pelton's remarks and Fuller's hands-on evaluation will translate into the right kind of pressure to get the FAA to remove the unreasonable obstacles it places before anyone trying to develop a new fuel. Specifically, GAMI still awaits approval of an STC it has requested to expand its fleet testing, an option that should be open to anyone trying to develop new fuels. Fuller's direct involvement is encouraging because the alphabets have been too cautious about expressing confidence in the process of finding a new fuel.

Why is the STC so important? For several reasons, none of which the bureaucrats obsessing about the ASTM process seem to see. First, if we're about to convert the entire GA economy to a new fuel, it would be nice to have a bunch of hours of real flight time on it. It would be good to run it through a cold winter, a wet spring and a blistering summer in Tucson. It would be nice to know how it behaves at -30 degrees in the flight levels and to find out if it chews up the seals in fuel trucks. You can't learn these things in test cells.

Further, because GAMI wants to do the STCs in a limited number of Cirrus aircraft equipped with the Tornado Alley Turbo, they've got the perfect laboratory for these tests. Those aircraft are equipped with sophisticated data logging instrumentation that will give us an unparalleled opportunity to see G100UL—or Swift or any other fuel—perform practically on an hourly basis. This will do what badly needs doing: It will give the fuel search credible visibility, reducing the erosion of confidence.

But the single best reason to approve the STC post haste is the simplest: There's no down side to doing it. None. The project is small and since the applicant does most of the work anyway, it won't tie up a lot of FAA resources. In opposing the STC, I'm sure some will argue the safety card, but that's absurd. Does anyone really think anything in aviation development is risk free? (Okay, so there is one downside: Pursuing the STC will put a dent in the hidebound notion that we've had a process for investigating fuels in place for 20 years and even though it has yielded nothing, let's keep following it.)

Jack Pelton has a piston-engine aircraft factory he would like to see busy again. He has lots of people he would like to get back to work. He understands how the lack of direction in fuel development threatens that and said as much last week.

I hope the right people are listening.

Comments (45)

Paul,

I'm glad AVweb is finally acknowledging the elephant in the room. I'm sure it's a factor in AOPA and Cessna's public statements about the problem.

By the way, in the interest of accuracy, I think you meant "principals" rather than "principles", and the word you're looking for in the MoGas article is "hygroscopic", not "hydroscopic".

-Mike

Posted by: MICHAEL MURDOCK | July 12, 2010 6:56 AM    Report this comment

Kudos to you Paul for pushing this issue in print - I think the gravity of this topic is lost on most people. Now what can we do to get a grass roots campaign going to shake the FAA tree to action this? Will the FAA have reps at AirVenture we can all visit?

Posted by: Steven Lefferts | July 12, 2010 7:24 AM    Report this comment

You're right on both counts. Missed these items in copy edit.

Posted by: Paul Bertorelli | July 12, 2010 7:41 AM    Report this comment

I confess to having been one of the negative ones. However, the work that GAMI has been doing as been a MAJOR bright spot,as they seem to be the only group that is putting together an interesting business case that COULD keep the price down. Instead of only focusing on the aviation business, GAMI sees the need of other engines that need pure fuel, and is also pursuing that market as well. That includes marine engines. If GAMI succeeds in expanding the market beyond aviation, there is a real possibility that the costs can be kept down. Paul, lets keep a close eye on GAMI's progress.

Posted by: Art Ahrens | July 12, 2010 7:51 AM    Report this comment

Good luck on a quick STC approval ... the FAA is still part of the federal government - the same federal government who has delayed cleaning up the largest oil disaster ever because of its myriad rules and regulations! These guys (the feds) simply trip all over themselves with their regs!

Posted by: JOHN AUSTIN | July 12, 2010 8:20 AM    Report this comment

I am wondering who is monitoring the age of auto fuel, I know if it is left in my tractor over winter it will not run in the spring. I'd rather use 3 year old 100LL than 3 month old auto fuel. What is going to be the life expectancy of the new purposed 94 octane? I have not heard any mention of that. If the 100LL is dropped then the parties responsible for that change should bear the cost of aircraft and engine modification or buy the aircraft after all the government did certify it for 100LL. Bill Schutzler

Posted by: Bill Schutzler | July 12, 2010 8:48 AM    Report this comment

Paul, I'm sure one of the reasons Jack and Craig went to the GAMI facility had to be because of your challenge for them to "get their ass on a plane to Ada". I believe if it wasn't for you and AVweb pushing the issue like you have, the industry would still be ignoring it. At this point, we owe as much thanks to you as we do to GAMI. Thanks.

Posted by: JOHN EWALD | July 12, 2010 9:34 AM    Report this comment

Thanks for the kind words. All roads lead to Rome so they would have gotten there eventually, thus no credit's due me. I'm just very alarmed that we're all not paying enough attention to this problem and it is fundamental to GA's survival. A little panic now is not a bad thing.

Posted by: Paul Bertorelli | July 12, 2010 11:35 AM    Report this comment

I'd like to think that another reason Fuller went to Ada is that a number of us IO520 owners have informed AOPA that if the standard becomes 94UL, we will no longer have any use for AOPA because we won't be flying.

Posted by: PAUL HEKMAN | July 12, 2010 1:06 PM    Report this comment

Paul Hekman, you may be right about AOPA's reason for going to Ada. I just hope that AOPA/Fuller also keeps in mind that whatever horse they back, it better be affordable. Otherwise, while you got the fuel you needed, there may be many who are priced out of aviation. The result will be the same - reduced AOPA membership when pilots stop flying whether due to lack of an appropriate fuel for their aircraft or an affordable fuel.

I hope AOPA is at least considering support of the dual fuel suggestions being made by Kent Misegades and others.

Posted by: Mike Wills | July 12, 2010 2:13 PM    Report this comment

For Bill Schutzler: As similar fuel as the 94 UL fuel with the same/higher performance has been produced by Hjelmco Oil in Sweden from time to time during 19 years and flown under several different weather and clima conditions in some thousand aircraft for probably a million flight hours. It is very stable in storage and the Hjelmco 94 UL fuel (labelled 91/96 UL) is good for storage normally 3 + years. When I say labelled 91/96 UL it means that the fuel does not have 91/96 octane numbers but has much more therein satisfying more engines than indicated. The reason is it labelled 91/96 UL was to provide an unleaded alternate automatically for all engines with a type-certificate for AVGAS 91/96 leaded.

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 12, 2010 3:04 PM    Report this comment

Lars, how is your fuel or any unleaded fuel able to be stored in anything other than lab conditions for more than 6 months. It is well documented that tel is the miticide responsible for inhibiting microbial growth and thus preserving avgas for extreme lengths of time. Something that plagues unleaded fuels and inevitably will pose a significant safety hazard if unleaded avgas is available to the masses.

Posted by: Brad Vaught | July 12, 2010 7:40 PM    Report this comment

Brad - Hjelmco solved those problems 31 years ago when we first developed our unleaded AVGAS 80 UL. That knowledge was transferred over to our current unleaded AVGAS 91/96 UL now in production continously for 19 years. So we have had commercial sales at 100 + airports for 29 years and we don,t have the problems you indicate. In Sweden we are like in Alaska -- we have places that are only accessable through mountain roads for approx 30 days a year -- so our fuels must have this capability of long storage times. Basically it is about to avoid certain components that are unstable. The current US AVGAS standard ASTM D910 also does not have it as mandatory to make the more extensive gum tests and other tests that I feel are necessary to protect the users from storage problems and detect any possible future problems already at the refinery level. The UK defense standard DEF STAN 91-90 for AVGAS on the other hand contains stricter requirements for gum testing on AVGAS than the ASTM D910. Leaded AVGAS is also open for lead precipitation during storage and this is on the other hand a risk with the leaded AVGAS 100 LL if you storage that product. cont

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 13, 2010 3:40 AM    Report this comment

As you indicate there are many small items that has to be solved before a fuel can go out into the users in a large scale. To have the AOPA and Cessna presidents witness some lab-tests is just the beginning and the start of the beginning. Nor the Swift or GAMI fuel as far as I know do meet the AVGAS standard ASTM D910 and thus will have to pass major tests and compromises to parameters in the current AVGAS standard before the fuel is there. With compromises I mean that the test parameters in the current AVGAS standard were not just taken from heaven - but put there intentionally because field problems occured and had to be taken care of and if you deviate you will have to make compromises which could be in engine performance, safety or reliability. Then when the fuel is there you have to have the engines certified to them, aircraft certified, find it economically to produce, find producers, find components, put it into production, distribution and sale. cont

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 13, 2010 3:41 AM    Report this comment

Further you have to have the educational part of putting a new product into the hands of the users. Also one has to undertand that all aircraft engines are not the same. Some are in good condition some are not, some are flying but do not certfication criteria. Some in less good condition may work on 100 LL but might not work on the the new fuel - causing problems and frustration on the market level. It probably affects serveral thousands of aircraft in the US. Parallelly you have to develop new engine oils that work with the new fuels and have such oils, tested, certfied, produced and put onto the market. So as a conclusion as Paul says is it is important to blow the whistles now -- because there is a very very long way to go and it is important to walk the way with care because doing mistakes can be ugly expensive.

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 13, 2010 3:41 AM    Report this comment

Lars, I think Swift and GAMI both believe their fuels can meet ASTM 910 requirements for 100 octane. If correct, we will have a 'drop in' replacement for the 100LL we now use. It would be transparent to the users and acceptable to the FAA so recertification of the fleet would not be required.

Price is a question. However, I've been flying since 1956, have always heard complaints the avgas is too expensive (as well as the cost of flying in general) but have not seen general aviation fall off a cliff because of this. Other issues have heavily impacted general aviation but somehow, people still fly.

Posted by: Edd Weninger | July 13, 2010 12:48 PM    Report this comment

Paul, thanks for staying with this issue and stirring the pot. I think everyone became complacent when avgas got an extension to continue to use TEL in 1991 and thought it would happen again. I too think this real this time.

Posted by: Edd Weninger | July 13, 2010 12:52 PM    Report this comment

Avweb/Paul - I've heard of the fuel that Lars Hjelmberg is talking about, but don't know much about it. I think it is a good idea for a look at how Sweden has an alternative, and could that work in the US? Sometimes we don't need to reinvent the wheel.

Posted by: Darren Tilman | July 13, 2010 1:10 PM    Report this comment

Ed - what is officially told is that the Swift fuel is heavier than jet-A1 and their patents lists very high aromatic contents. This makes such a fuel if I am correct well outside ASTM D910 distillation range. The GAMI fuel I cannot speak so much about but as both the GAMI and SWIFT fuels are fully hydrocarbon and if they actually were meeting the current AVGAS standard ASTM D910-- they would not need any certification or any approval at all. And if they were drop in fuels -- they are just as the name says drop in fuels. Why then involve the ASTM or the FAA or anyone else? I dont,t think it is that easy. If they were drop in fuels meeting the ASTM D910 AVGAS standard - we would all already today been flying on these fuels. There are more we don,t know about and also the respective companies don,t know about. So I think it will be a difficult path to go.It is also not so simple to walk the path because there are less than one handful of people that really knows how to walk the path in the entire world.

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 13, 2010 1:42 PM    Report this comment

Edd, gen av may not have fallen off a cliff, but I dont think you can deny that there has been a significant decline over all of those years?

I started flying in the early 80s, but put it aside to raise a family. Picked it back up in the late 90s after my kids were grown and out of the house. I love to fly as much as anyone, but you have to have your priorities.

I'm reaching another milestone soon - retirement. I have plans to move to a residential airpark (I think you've previously mentioned you have property at AZ-82? Me too). With retirement will come a drop in income. Couple that with a large increase in the cost of flying and my plans may need revision. I dont know what my cost threshold is and will fly as long as I am able, but there is a threshold somewhere. Just hope I dont reach it.

Posted by: Mike Wills | July 13, 2010 2:21 PM    Report this comment

I dont know what my cost threshold is and will fly as long as I am able, but there is a threshold somewhere. Just hope I dont reach it.<<

Do the phrase LSA mean anythin't to ya, Ruby? (You should be old enough to get the joke.)

Seriously, a multiple member partnership in a legacy LSA is about as cheap as it gets. Can't do much with it, I'll concede. But it does provide stick time.

Posted by: Paul Bertorelli | July 13, 2010 2:57 PM    Report this comment

>>Seriously, a multiple member partnership in a legacy LSA is about as cheap as it gets<< Really interesting point. I find a lot of owners flying Cherokee 6's around solo and then complaining about the cost. While I think it benefits us all to minimize the input costs of flying (fuel, insurance and repair bills where it makes sense) one of the easiest ways to reduce the cost of flying is to examine our missions very carefully and make sure we're flying the right airplane. I am intrigued by the perception that light sport is the cheapest way to fly - in most cases I think you'd find the lowly Cessna 150 is probably the cheapest thing going when considering acquisition, maintenance and fuel costs (next to an ultralight - and nothing wrong with those either)

Posted by: Josh Johnson | July 14, 2010 9:38 PM    Report this comment

150 the cheapest? A decent mid-70s example--which aren't easy to find--retails in the $20s. On the legacy LSA side, Champs are in that range and so are the low end of the Cubs. With no electrical systems or radios, the taildraggers are really cheap to maintain. Of course, you can't do much with them other than fun flying. Presumably, a 150 is fast enough for modest cross country flying. You can use it for IFR.

But for older pilots, the 150 may be out because of medical issues. That makes LSA very attractive. In a four-way, the Cub costs me $100 a month and $10 an hour, plus gas. I can't imagine anything much cheaper. Like you say, depends on the mission.

Posted by: Paul Bertorelli | July 15, 2010 3:43 AM    Report this comment

150 the cheapest? A decent mid-70s example--which aren't easy to find--retails in the $20s. On the legacy LSA side, Champs are in that range and so are the low end of the Cubs. With no electrical systems or radios, the taildraggers are really cheap to maintain. Of course, you can't do much with them other than fun flying. Presumably, a 150 is fast enough for modest cross country flying. You can use it for IFR.

But for older pilots, the 150 may be out because of medical issues. That makes LSA very attractive. In a four-way, the Cub costs me $100 a month and $10 an hour, plus gas. I can't imagine anything much cheaper. Like you say, depends on the mission.

Posted by: Paul Bertorelli | July 15, 2010 3:44 AM    Report this comment

Paul is right on about a Cub being a good inexpensive way to keep flying. I own one solo, and get to fly 2-3 times a week. Up until recently I could still find Mogas without alcohol to reduce the cost even further. My biggest complaint about the Cub is the lack of speed and comfort. It takes too long to go get a $100 hamburger if it is over 50 miles. It is a shame the Cessna 140s and 150s are not included in the Light Sport category. Buying a newer faster LSA is out of the question.

Posted by: Jake Jacoby | July 15, 2010 5:30 AM    Report this comment

I guess with the cub, if you own one already and the covering is okay it might be a little cheaper. Guys are getting 30-35k for a nice J3 nowadays. For the 150's, if you're happy flying a 1940's cub, why not get an old straight-tail 150 for 15k. IMHO, the biggest issue here isn't including the Cessna 140/150's in the Light sport category but why we need a 3rd class medical anyhow - especially for say, 180hp or less fixed gear (although I don't think a medical is applicable in any case for non-commercial ops) I mean, if you can take your RV (not the Van's kind) cross country without a medical - I don't see the issue if you want to do it in a Bonanza! There's no measurable safety reason to do it. Perhaps it's time for a new grass-roots effort to change the medical certification standards.

Posted by: Josh Johnson | July 15, 2010 6:57 AM    Report this comment

The med certs are a larger, long-term issue. For the short term, legacy LSA does exactly what it was intended to do: Provide a direct, cheap path to flying for those with low expectations.

Conceding new LSAs are a non-starter. And so likely are good-buy older conventional airplanes as a market growth force. The demographics and wealth curves are going in the wrong direction.

Posted by: Paul Bertorelli | July 15, 2010 7:39 AM    Report this comment

As the search continues, perhaps we should visit a company that has already done high octane, no lead development http://www.bazellracefuels.com/racingfuels.htm At least three of these fuels are nonleaded. Sunoco has worked to meet the demands in the Nascar circuit successfully and their knowledge combined with a modern dual redundant ignition system could breath life into an industry that is quickly relegating all piston GA to the ranks of LSA operations. This industry needs higher expectations of itself and a more cost conscious attitude if GA as we know it intends to survive.

Posted by: Larry Forrest | July 15, 2010 9:15 AM    Report this comment

Legacy LSA does provide a cheap hassle free approach for existing pilots, but it's a no-go for flight instruction. With the exception of the Ercoupe, I don't know of any tricycle legacy LSA's. The reason the tri-pacer and the 172 were developed is that too many people were wrecking tailwheel airplanes during training. This makes it nearly impossible to get insurance for a light sport training operation using tailwheel aircraft with student solo privileges. If we're not bringing new pilots into the fold, we're in big trouble.

Posted by: Josh Johnson | July 15, 2010 11:02 AM    Report this comment

You're kind of slicing apples and oranges here. We were actually referring to LSA in the context of the older pilot who wants to keep flying but doesn't want to maintain a medical or spend a lot of money. An old LSA-compliant taildragger is just perfect.

The flight student looking to get rated will likely go the flight school route. He will pay around $110 an hour for a new LSA, plus instruction.

As for the tail dragger insurance thing, it's a bit of a fallacy. Outside the flight school context, insuring them is not especially onerous. Insurers do require an exstensive checkout, but it's a doable thing.

Posted by: Paul Bertorelli | July 15, 2010 12:53 PM    Report this comment

Yeah - I know you can get insurance for a privately owned taildragger but you're right, it will be expensive if even possible for a flight school. I disagree about your comment on the flight school route. Around here, there are no large flight schools - we just have independent CFI's looking to rent aircraft from an FBO. And no new LSA's around here to rent either. I just don't see $110 an hour really selling for the "budget conscious" pilots that the sport pilot certificate is catering to. Sport Pilot great for those of us who already have certificates - but I don't think light sport is doing nearly what was intended for new pilot starts. I'd rank the major issues threatening aviation (in no particular order) as: (1) Fuel (2) Loss of airports (3) Lack of new pilots (4) User fees. The lack of new pilots is at least as important to the future of GA as is the 100 octane fuel issue - we really need to be addressing this.

Posted by: Josh Johnson | July 15, 2010 5:40 PM    Report this comment

Paul, there is a big downside to G100UL... it makes the folks who have been putzing about for 20 years look bad.

GAMI, with lots of experience testing fuel system components, apparently went and did the right kind of research... researching the research that was done in the mid 20th century, when gasoline *was* king. Standing on the shoulders of giants, with an engine test bed those giants could only dream about, they got results.

I don't have a dog in this fight, if something comes up that's better than G100UL, or Swift, great. However, it's time for the alphabet groups to rally behind a demand for a high octane fuel and to immediately abandon the 94UL abomination that would smash GA to bits.

Posted by: Greg Goodknight | July 15, 2010 6:00 PM    Report this comment

Greg: The 94 UL (testfuel) and Hjelmco 91/96 UL (meeting or execeeding 94UL) are the only unleaded real AVGAS presented that 100 % meet the US standard for AVGAS - the ASTM D910. The standard has its parameters basically based on trial and error. As the GAMI and Swift fuels are not 100 % ASTM D910 complaint and might never be -- are you actually saying that we shall accept fuels with parameters where we have to make compromises in performance, safety or reliability? Say - that the GAMI and Swift fuel efforts fail -- and you ask for abandon the 94 UL what shall GA do then? You are asking people to be wizzards. Reality is that everyone has to accept what is possible to achieve. I have been long in this business and there has during the last 30 years always been an unleaded 100 octane fuel around the corner. In reality only two fuels have made it to the market and those are the Hjelmco AVGAS 80 UL in the year of 1981 and the Hjelmco AVGAS 91/96 UL in the year of 1991.

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 16, 2010 4:40 AM    Report this comment

Greg: The 94 UL (testfuel) and Hjelmco 91/96 UL (meeting or execeeding 94UL) are the only unleaded real AVGAS presented that 100 % meet the US standard for AVGAS - the ASTM D910. The standard has its parameters basically based on trial and error. As the GAMI and Swift fuels are not 100 % ASTM D910 complaint and might never be -- are you actually saying that we shall accept fuels with parameters where we have to make compromises in performance, safety or reliability? Say - that the GAMI and Swift fuel efforts fail -- and you ask for abandon the 94 UL what shall GA do then? You are asking people to be wizzards. Reality is that everyone has to accept what is possible to achieve. I have been long in this business and there has during the last 30 years always been an unleaded 100 octane fuel around the corner. In reality only two fuels have made it to the market and those are the Hjelmco AVGAS 80 UL in the year of 1981 and the Hjelmco AVGAS 91/96 UL in the year of 1991.

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 16, 2010 4:40 AM    Report this comment

Greg - I think we're way too premature to call Swift and GAMI the winners in the fuel crisis. Swift and GAMI sound good, but we don't know for sure the cost, or even if the stuff will work. I know that engine mods and reduced output really upset people, but no fuel at the pump or $10 avgas is a non-starter too! As for me, I'm open to any options including 94UL until we've got a certified, economical replacement to 100LL that's approved to run in my airplane available at my local airport.

Posted by: Josh Johnson | July 16, 2010 12:36 PM    Report this comment

Not calling any winners here. Just the target. 100 octane, and *no* *one* is talking about $10/gal targets except for the folks who would sell out those of us with high performance aircraft, the ones using 70% of the fuel and keeping local A&P's in business, to save themselves a few cents a gallon.

Posted by: Greg Goodknight | July 17, 2010 7:26 PM    Report this comment

For me, the target is a fuel that will run in most if not all airplanes without any or with minimal modifications and is cost effective (same price or lower than 100LL). Lars makes a very valid point about the tried and true. Personally, I'd like to just keep 100LL, but fat chance on that!

Posted by: Josh Johnson | July 17, 2010 8:45 PM    Report this comment

Lars, I don't think a specification developed around a leaded fuel needs to be a straightjacket to force a future unleaded fuel to meet. We have better tools to evaluate fuels than when 20 and 30 years ago when you developed your fuels.

Rather than cast aspersions against the safety, performance and reliability of your possible competitors, try actually challenging them on their testing regimen. I suspect the GAMI test engine and their TAT TN Cirrus test aircraft are a more rigorous test than ASTM D910 ever experienced during its development.

While I accept you and Hjelmco as true innovators, so are Swift, GAMI and whoever else is out there in the shadows.. We now have a couple of US Senators who have actually flown using 100UL avgas, and until we have evidence those fuels will not lead to unsafe fuels in production, I have to believe there are candidate 100UL fuels that are REAL.

Posted by: Greg Goodknight | July 18, 2010 8:37 PM    Report this comment

Greg: There is no intent to cast any aspersions on GAMI or SWIFT it is just pure reflections about my own experience when sending inventions to the ASTM. I agree with you that not all of the requirements of the US standard ASTM D910 for AVGAS are 100 % necessary but if you put one or any of them aside you have to make concessions. cont

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 19, 2010 3:10 PM    Report this comment

cont For example the freezing point - better than - 58 C actually only affects a very few users - the ones flying above about FL 300. There are a few piston aircraft that do that - but most of us will never to it during our entire career - but still the requirement is there. If we took that requirement away - yes we could blend the fuel with fuel components that might widen our horizon -- but the end product would still give all users restrictions in the use of the new unleaded AVGAS - however only a few might in reality be affected. This is an example where I mean we can ease a little in the requirement - but if you go to the distillation of the fuel -- then we are coming to operational restrictions that will affect us all -- and that,s where I have the concern of the present formulas as far as I understand. I don,t have all information about the GAMI or SWIFT fuels so I cannot comment any more - than done before. If the fuels are outside the parameters set in the current ASTM D910 standard - these fuels have a path to go to prove that they are safe as unifuels or some of us do have to accept compromises in performance, safety or reliability. As said many times - I applaud everyone putting resources and money into this task to find a high octane AVGAS for everyone.

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 19, 2010 3:10 PM    Report this comment

So, Lars, what I think you're saying is that unlike going 94UL which would be permitted under existing type certificates for aircraft certificated for 80/87 avgas (or really any avgas less than 94UL - I think there was a 90/94 grade specified for some aircraft), the 100UL contenders will likely be a new ASTM spec. Interesting. If this is the case, certification of a fuel that doesn't meet ASTM D910 will require a model-by-model certification and testing of the aircraft, including 80 octane and 100 octane aircraft (and perhaps some minor mods as in venting, boost pumps or who knows what else due to vapor pressure or freeze point or whatever) before being able to use the fuel, much like a mogas stc for low compression engines. If this evolves into all of the piston fleet having to STC our aircraft for 100UL that's far from a drop-in replacement - even if the mod is just paperwork. Am I missing something here?

Posted by: Josh Johnson | July 19, 2010 4:10 PM    Report this comment

Josh - the 94 UL is intended to be a drop in fuel for AVGAS 80, AVGAS 91 aircraft and engines. For each AVGAS 100 engine on a selected basis each one has to be tested and approved for this fuel. As the 94 UL fuel is complying (? no-one knows yet because only a test fuel exists) with existing standard ASTM D910 I assume that a blanket approval for the airframes would be made. For the new potential fuels not meeting standard ASTM D910 you will need both engine approval and airframe approval. Airframe approval could be partly simplified by testing candidate fuels in "general aircraft conditions" because airframe builders tend to use same/similar material in gaskets, build fuel tanks in the same way etc. But in principle it has to be made for each individual airframe type certificate as far as I understand it. For example we know the SWIFT fuel is more heavy than JET-A fuel. The SWIFT people has to show that the current aircraft fleet can handle that. For example loading strenght on wings have been calculated on fuel with normal AVGAS density. Perhaps a restriction has to be put in on a maximum amount of fuel in the tank even if the tank is not full.(and this we easily can live with - but it has to be calculated) On the engine side the SWIFT people will have to show that the carburettor can handle this heavy fuel both when the fuel is in hot clima + 50 C ? and gets lighter but also at minus 58 C when the fuel gets really dense.

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 20, 2010 3:23 AM    Report this comment

Even if the carburettor might work it will also have to show how a carburettor setting for a very heavy fuel (adjusted float) will handle when a refuelling is made with a very light fuel as AVGAS or MOGAS. Also how will the carburettor handle fuel flow and evaporation for a very heavy fuel during various G-constraints etc. In summary -- as soon as you outside the anticipated parameters of the existining AVGAS standard a lot of things have to be tested and confirmed to be safe. We might end up with that we can live with the new fuels - but when we accept compromises in performance, safety or reliability. Having one or two senators to look at the matters will not secure aviation safety - which it all is about. I have limited information about the SWIFT and GAMI fuels so I cannot say their fuels need to have STC;s for any aircraft or the entire fleet out there - but at the end someone has to take responsibility of the public safety and flight safety of the piston aircraft fleet.

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 20, 2010 3:24 AM    Report this comment

Even if the carburettor might work it will also have to show how a carburettor setting for a very heavy fuel (adjusted float) will handle when a refuelling is made with a very light fuel as AVGAS or MOGAS. Also how will the carburettor handle fuel flow and evaporation for a very heavy fuel during various G-constraints etc. In summary -- as soon as you outside the anticipated parameters of the existining AVGAS standard a lot of things have to be tested and confirmed to be safe. We might end up with that we can live with the new fuels - but when we accept compromises in performance, safety or reliability. Having one or two senators to look at the matters will not secure aviation safety - which it all is about. I have limited information about the SWIFT and GAMI fuels so I cannot say their fuels need to have STC;s for any aircraft or the entire fleet out there - but at the end someone has to take responsibility of the public safety and flight safety of the piston aircraft fleet.

Posted by: Lars Hjelmberg Hjelmco Oil Sweden | July 20, 2010 3:24 AM    Report this comment

In referance to the statement below I fail to see how 100LL fuel will increase aircraft sales. Bill Schutzler

Jack Pelton has a piston-engine aircraft factory he would like to see busy again. He has lots of people he would like to get back to work. He understands how the lack of direction in fuel development threatens that and said as much last week.

Posted by: Bill Schutzler | December 11, 2010 9:26 AM    Report this comment

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