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Issue link: http://airportbusiness.epubxp.com/i/397645
INDUSTRY INSIDER October 2014 airportbusiness 29 "I like to do things that no one else has ever done before," he says. "That's why I helped develop unleaded fuels for motorsports. That's why I like working on developing an alternative fuel for aviation gasoline (Avgas). Nobody's done it before, so it's a good place to be." In this game of both knowledge and skill, Shell emerged as a front runner in December 2013. With Shea at the helm of its aviation fuel research and development efforts, the global supplier of avia- tion fuels and lubricants became the first major oil company to develop a lead-free replacement for Avgas, which is now being evaluated in strict regulatory approvals process. Airport Business chatted with Shea recently to learn more about the new fuel, the testing results they've seen, and where the alternative fuel stands in the regulatory approvals process. WHAT IS THE HISTORY OF SHELL'S WORK ON AN ALTERNATIVE FOR LEADED AVGAS? Our work goes back a long way. It began as a motorsports project in 2004 when we were looking for an unleaded fuel that could replace the leaded fuels in the U.S., Canadian and Australian motor- sport markets, where leaded race fuels were still commonly used. In 2008, we completed that work and launched those fuels. It was then that we noticed how the Avgas sector was also under a lot of pressure from the EPA to remove lead. We decided to transfer the technology we used in motorsports fuel to an Avgas product. That work began in earnest in 2010-2011. WHAT WERE SOME OF THE CHALLENGES IN DEVELOPING AN UNLEADED AVIATION FUEL? There are two primary areas that make that challenging. The first one has to do with storage stability. Aviation gasoline tends to be stored for long stretches of time. Because of that, you have to be very specific about the types of molecules you put into the fuel to ensure that they don't evaporate too quickly. Motorsports has the opposite problem. The other part has to do with the specifica- tions of the fuel. In motorsports, there really is no specification, it's open. You design a fuel that works the best, and that's about it. In aviation gasoline, there is a specification for the current leaded product—ASTM D910. This specification shows all of the current grades of Avgas and provides the physical properties they need to meet to be sold as that grade. We wanted our fuel to, if not match the grade for 100 LL exactly, be as close as possible to it. That is where the challenges came out because aviation gasoline has to be able to withstand very cold tempera- tures. We had to modify the fuel to give it the low temperatures properties of Avgas. WHAT KINDS OF RESULTS ARE YOU SEEING WITH THE ALTERNATIVE FUEL SHELL HAS DEVELOPED? Our fuel is within the ASTM test specs range, which is quite a wide specification. There are still variants in the fuel being tested. The idea behind our initial flight tests was to demonstrate that the fuel was compatible enough to pass the initial checklist in terms of compatibility with the aircraft and the engine. This testing centered on whether there were any noticeable differences between our fuel and 100 LL. The data we've gotten back so far shows that the differences are indistinguish- able. The pilot—who controls the fuel flow to the engine, experiences the condition of his aircraft, and typically fuels it—can't tell there's a different fuel in the aircraft. The alternative fuel should be a drop-in type of fuel so that when you use it, you don't know that you're using a different fuel. WHAT IS THE TRUE DEFINITION OF A DROP-IN FUEL? Our take on the definition of a drop-in replace- ment fuel is that everything from once the fuel is blended and ready to ship, to how you transport it, store it, fuel the aircraft, and how it performs in the aircraft should all be indistinguishable from 100 LL today. But it really depends on what your frame of reference is. If you're the pilot, you want to know if you put this fuel in your aircraft will you notice anything different? Does it run the same way? Do you fly the aircraft the same way you used to with 100 LL? A drop-in replacement should be completely transparent to the pilot. But an OEM will have a different definition for a drop-in fuel. OEMs want to make sure the alternative fuel is compatible with all the materi- als it comes into contact with for the long term. Aircraft can be out there in the marketplace for decades so long-term compatibility is key. Most people take it as a given that you're going to meet the engine performance part in terms of how ON THE CHALLENGES OF DEVELOPING A NEW FUEL... We wanted our fuel to, if not match the grade for 100 LL exactly, be as close as possible to it. That is where the challenges came out because aviation gasoline has to be able to withstand very cold temperatures. We had to modify the fuel to give it the low temperatures properties of Avgas. ON SHELL'S DEFINITION OF A DROP-IN FUEL... Our take on ... a drop-in replacement fuel is that everything from once the fuel is blended and ready to ship, to how you transport it, store it, fuel the aircraft, and how it performs in the aircraft should all be indistinguishable from 100 LL today. ON WHEN AN ALTERNATIVE FUEL MAY BE AVAILABLE... ... it's a very large undertaking. You're looking at effectively certifying a fuel for every engine and aircraft in the United States.