What If They Had A PAFI And No One Came?


Swift Fuel’s announcement that it’s bailing out of the FAA’s troubled Piston Aviation Fuels Initiative had an inevitability about it. Following the FAA’s announcement in June that it was suspending work on finding suitable unleaded replacements for 100LL, a not-that-subtle whiff of a certain metaphor related to chairs on the deck of a doomed ocean liner was detectable.

Without saying exactly that in its press release, Swift says it’s abandoning PAFI’s contorted path in favor of the same STC process already underway by General Aviation Modifications Inc. and, more recently, Phillips 66 partnered with Afton Chemical. Swift used the term “alternative pathway,” which, as far as I know, can only be an STC.

And then there was one. That would be Shell, who, along with Swift, had one of the two fuels perking through the PAFI process. Shell’s intentions are unknown, but based on Paul Millner’s reporting in this blog, the company doesn’t appear to be particularly impressed that lead is that bad. I won’t be the slightest bit surprised if they take a powder on PAFI and abandon the unleaded avgas effort entirely.

Fiasco doesn’t do justice to describing any of this. PAFI emerged because the industry—airframers, engine manufacturers, refiners—reasonably believed nothing would move off the dime until the FAA brought the various parts and pieces together in some kind of project that would yield a publishable standard for unleaded avgas similar to the ASTM D910 doc that has served leaded fuel so well. The FAA imprimatur was seen as must-have. It may turn out to be the poison pill, by the looks of it, or least the process is.

It appears to have run off the rails because all of the fuel companies—and especially Shell and Swift—came at the problem with unique chemical solutions that delivered the required 100 octane, all right, but were too different from 100LL to serve as the vaunted drop-in replacement. It’s different for conventional avgas because although one refiner’s alkylate may be a little better than the other’s, it’s chemically the same stuff. And tetraethyl lead is tetraethyl lead; use a little more or a little less to gin up the octane.

At AirVenture last year, the FAA admitted that each of the two fuels would cover a portion of the piston fleet, but neither would adequately cover all of it. And as Millner reported, non-linearities were noted when the fuels were intermixed with each other and with 100LL. Why this wasn’t foreseen as a cautionary for PAFI is puzzling, since the 50-cent tour of any refinery—or a high school chem lab—would suggest as much.

To further stymy PAFI’s potential for success, once the fuels entered the process, they couldn’t be tweaked or reformulated to address whatever shortcomings the very testing was supposed to reveal. My admittedly imperfect understanding of this is that it had to do with proprietary concerns and government vendor rules. But as GAMI’s George Braly pointed out, this defies the basis of research, which requires testing, fixing and retesting in a relentless intellectual pursuit of solving the problem at hand.

So now what? Will Shell re-enter the stalled PAFI process? And if so, can it address whatever shortcomings its fuel happens to have? If so, bully. It might own the market, land a workable ASTM standard and make a mint selling the stuff—or licenses—worldwide. I don’t think this is answerable right now.

Otherwise, welcome to the Balkanization of avgas. GAMI, Swift and Phillips are all pursuing discrete STCs. It’s unlikely all three of those fuels will meet the same standard, or maybe any standard, so if the STCs are approved, how is this supposed to work? Does one airport have Swift, another GAMI and yet another Phillips? And if so, can I intermix them and who’s going to warrant that this can be done safely. (Hint: It’s not going to be PAFI.)

Perhaps the STC applicants should add to their already burdened plate miscibility testing. But how do you do that until the other guy’s STC is approved? It gives me a headache trying to imagine an FAA bureaucrat with the guts to sign off on the testing program for that.

Don’t let it escape notice that Swift chose not to go quietly into that good night by withdrawing from PAFI, but issued a deliberate press release distancing itself from the PAFI rubble. I think it needs to do that to declare that it’s still in the game, but now on its own terms.

As Millner mentioned earlier this month, there are significant vulnerabilities here. Just because the current EPA has suspended the finding of endangerment against tetraethyl lead, that’s no guarantee it won’t re-emerge later, either by administrative fiat or court order. If GA settles back into its comfortable embrace of lead, we may have no ready replacement when the effort to ban it finally gets teeth. And there’s Europe and perhaps Asia to think of. Both have their own concerns about leaded fuel.

In the smoke curling up from PAFI is this cheery thought: Those who thought the FAA was engaged in picking winners and losers via PAFI can take comfort from the notion that now the free market, not regulators, will have to sort this out. Maybe it was wrong to think the only way to solve this seemingly intractable problem was to have the FAA oversee it and jolly it along. We can all plainly see where that got us.