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EAA Remains Deeply Committed to Unleaded Fuel Development Effort

As EAA meets this week with members of the Piston Aviation Fuels Initiative (PAFI) in New Jersey, it is a good opportunity to update the general aviation community on the effort to ensure a managed and orderly transition from 100LL avgas to the piston aviation fuel of the future.

July 9, 2015 - The Piston Aviation Fuels Initiative (PAFI) is a collaborative government/industry effort to identify, test, and ultimately approve high-octane unleaded fuels for use in the general aviation piston fleet. The program stems from decades of EAA-supported industry test programs and the eventual recommendations of a transition aviation rulemaking committee on unleaded avgas that was first requested by EAA and several other aviation organizations. The PAFI program is well underway with four fuels from three separate companies having been admitted into the first phase of evaluation, which is due to be complete at the end of this year.

Phase one of the PAFI program is focused on evaluation of the properties of the fuels, materials compatibility, impact on test rig representative fuel systems, environmental and toxicological analysis, hot and cold storage stability, and some basic detonation testing, among other qualities.

The program is aggressive in its timelines and very ambitious in its breadth. To accomplish all that needs to be done in just a few short months, work is being divided among two universities, the FAA Technical Center in Atlantic City, New Jersey, and several internationally recognized fuels testing laboratories. Test specifications for each of the fuels are simultaneously being developed through the standing fuels committee process within ASTM.

At the same time, test plans are being developed for the second phase of testing that begins in 2016, which will focus on full-scale engine and aircraft testing - including evaluation of the impact on propeller vibration brought about by potential changes in the combustion cycle introduced by new fuel chemistries.

All of this work is coordinated and managed by a body known as the PAFI Steering Group whose membership is composed of aviation and petroleum industry representative organizations and the FAA. EAA is one of the founding members of the PAFI Steering Group and your advocacy and safety department devotes significant staff time and travel to help ensure that a viable unleaded future will exist for all facets of sport and recreational aviation in the future.

EAA has a long history working with fuel test programs, standards, and specifications dating back to the 1970s, when EAA pioneered the autogas STC program. That beginning led to EAA being an integral part of the community of petroleum companies and associated industries that have been working to find a high-octane, unleaded replacement for 100LL avgas since the 1990s. Today the PAFI process is the culmination of all those years of work as the program evaluates four fuels from Swift, Shell, and Total.

This complex and difficult work requires the coordination of many parts of government, the aviation industry and the petroleum industry. A new unleaded fuel is still years away but PAFI is the best hope for not only ensuring the viability and safety of new fuels but also facilitating the transition of the existing fleet to use unleaded fuels on a wholesale and coordinated basis.

The ultimate goal of PAFI is to achieve something as close to fleet-wide certification as the fuels will allow, something that could never be achieved by individual STC approvals. This is a daunting task and something the FAA has never done before. Marshaling the resources necessary to conduct the testing and develop the data required to support such a massive certification undertaking is no small feat and EAA is committed to doing everything in its power to help make this a reality.

Removing lead from aviation gasoline is not simply a matter of environmental expedience or regulatory threat. This year the last country to use lead in its automotive fuels is slated to transition to unleaded gasoline, leaving aviation as the sole remaining consumer of tetra-ethyl lead. The loss of that one remaining small country’s use of lead in mogas means that two-thirds of the remaining worldwide lead marketplace will be eliminated, leaving GA as the sole consumer of a product from a sole worldwide supplier whose marketplace has but been all but eliminated. This is a tenuous place for our community to base its future.

The die is cast; there will be an unleaded future for general aviation. It is the job of PAFI and the effort of EAA to ensure that unleaded future is reached in an orderly and successful manner that meets the needs of as much of the existing fleet as technologically and economically possible. EAA is committed to this effort and is pleased with the progress to date.

But make no mistake; this is very complex and difficult work. Lead is by far the best anti-detonation substance for fuels known to mankind. Removing just a gram or so of lead from the fuel requires that other octane enhancers be added in massive quantities, sometimes making up as much as half to three quarters of the fuel itself. This changes everything about the chemistry of avgas as we have known it, and ascertaining the impact of those changes in a way that represents effects on the entire GA fleet is a daunting task. Ultimately our greatest concern is for your safety, followed closely by the economics and availability of the new fuels and protecting your investment in your aircraft. These matters are always at the top of our minds as we work our way through this technologically complex and challenging effort.

In the meantime, EAA and the PAFI Steering Group are working with the existing supplier of tetra-ethyl lead to ensure that leaded aviation gasoline will continue to be available throughout the timeframe required to transition to unleaded fuels in the future. Right now this timeframe is indefinite as we are only still in the early stages of evaluating the best of the candidate fuels entered into the PAFI process. As testing progresses, the properties and capabilities of the fuels will become more apparent - and so too will things like the applicability and impact on the existing fleet, and thus our ability to make a smooth and timely transition. Regardless, any transition to unleaded fuel is still some years away as the data necessary to support fleet-wide certification will not be completely developed until 2018 at the earliest.

EAA will continue to keep its members informed of the progress of PAFI as time goes by, but in the meantime, rest assured that we are deeply committed, as we have been for years, to ensuring that fuels appropriate to the GA fleet remain available for decades to come.

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