Ive been covering the aviation piston fuel story intensely for four years now and off and on for a lot longer than that. And honestly, the more we bump along toward an eventual replacement for 100LL, the more confusing and confounding the process appears to be. Not that Im discouraged, for there will be a replacement. Its just that getting there is going to be a bureaucratic grind that will be even more eye glazing than most of us might have imagined.
Heres where we are now: Loving as it does acronyms, the FAAs Unleaded Avgas Transition rulemaking committee (UAT-ARC) came up with something called the Piston Aviation Fuels Initiative or PAFI. This isnt really an entity, but a process overseen by the FAA and industry to accept potential candidate fuels, screen them and then test them before theyre approved for fielding. PAFI is set up to receive up to 10 fuels, but only two will emerge from that process. The FAA insists that its not picking winners or losers, but it clearly is. If 10 are submitted, only two will go through the final testing process. Thats a function of FAA budget limitations and the fact that the industry and government decided that the fuel testing would be centralized and done by the FAA, which front-loaded the process to be incapable of conducting complete testing on all comers. They just dont have the money.
And judging by last months ASTM meeting in Tampa, there might not be that many comers anyway. Right now, there are three: the recently announced Shell project and fuels from General Aviation Modifications, Inc. and Swift Fuel. The deadline for further submissions is July, so time is short. Asking around at ASTM, I didnt get the impression that everyone-and maybe anyone-assumes there will be more candidate fuels. No one seems to know. Its also not clear if more candidate fuels are a good thing.
Normally, the more products there are, the more the competition and thats good. But it could very well be that there are only so many ways to produce a 100-octane, unleaded fuel and the clear trend seems to be an aviation alkylate-based fuel with aromatic additives. Swift Fuel is the outlier, with a binary blend of mesitylene and isopentane. Given the economics, Id be surprised if anyone submits a fuel far outside this paradigm, but well know by July. One source told me he expects to see a submission by the French refiner, Total, and its hard to believe that ConocoPhillips, a major avgas producer, wont throw a candidate on the table.
On the other hand, I cant even begin to guess how refinery executives view the PAFI process and how eager they are to get tangled up in it. As I see it, it has two significant flaws. First, the call for fuel candidates follows the federal contract process, which is great for buying bombers and tanks, but an imperfect fit for fuel to be developed for a consumer market. This came to light at the FAAs presentation at ASTM when several company representatives asked, hypothetically, if they submitted a fuel that failed to make it through the screening, could they learn why. The initial answer was no, because government contract rules preclude that sort of thing. But the FAAs Peter White said the process is still a work in progress and may have flexibility. The screening and testing is designed to be a data-generation process and the data is supposed to be shared.
But the basic idea is flawed, in my view. Its the equivalent of the airline industry deciding it needs a new 250-passenger aircraft and submitting the designs to the FAA. The government then does the testing and picks which one goes to market and it cant test them all because it doesnt have the money. This works in the defense industry because the government is the customer, but it doesnt work as well when the government intervenes to do what free markets normally do: pick winners and losers based on price and merits.
Another aspect of the PAFI process I dont agree with is that one checklist item is to evaluate the fuel submitters business plan-in other words, is the companys fuel realistically producible and can it make a profit producing it? Again, thats for the market to sort out after the fact, and not for the FAA to predetermine based on its standards. This puts smaller companies like GAMI and Swift at a disadvantage against a Shell or a ConocoPhillips who will quite naturally have more mature and impressive business plans. Its a testament to how perverse this entire fuel replacement problem has become that the industry sat around a table and agreed to the process theyre stuck with. But no one could come up with anything better and Im not sure I could, either, although I dont understand why the submission process came to be governed by contract rules.
The FAA explained that each submitted fuel will be judged by a complex matrix designed to make the evaluations as objective as possible. There will be two stages, an initial screening and, for the two that make it through that process, detailed testing. The details of the matrices havent been worked out yet, which may be another cause for pause for any companies thinking about submitting a fuel. Even though the FAA appears to have made a bona fide effort to make the evaluation process neutral and unbiased, Lars Hjelmberg, who has been making fuel for 30-plus years in Europe, told me after the meeting that theres always some risk of what he calls a political fuel.
By that he means an evaluation process tilted in favor of one fuel or another for other than strictly technical reasons. The ASTM is supposed to be a consensus organization, but it has competing and conflicting member interests, as all organizations inevitably do. The same applies to the FAA. To minimize the effects of that, the PAFI process will use a pair of committees with industry representative to review the fuel data and check off the boxes on the yet-to-be-developed evaluation matrices. But conflicts of interest are always a danger.
While this entire construct doesnt give me the warm fuzzies, I think it has a reasonable chance of succeeding and Im actually quite confident a workable 100-octane fuel will emerge one way or another. The largest worry seems to be that whatever fuels get the nod wont match the ASTM D-910 leaded avgas spec closely enough to drop right into the distribution and regulatory structure. If that does turn out to be the case-and no one can say at this point whether if it will or it wont-then someone may need to do some additional certification work. But who? And who will pay for it? The engine manufacturers and airframers are hoping to avoid this scenario for obvious reasons. And to do that, theyre depending on an approval process Id generously describe as less than perfect.
Its going to be an interesting three or four years.
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