"Smart" ignition systems are programmed to automatically change (retard) ignition spark timing at the onset of detectable detonation. This would automatically reduce engine power. Imagine seeing a panel-mounted "power reduced" light start blinking as the runway end looms in the windshield. In addition to the operational snafus, this would present a formidable certification headache.
All of today's existing engines can be made to run on 94UL, but the changes required for a fleetwide conversion would cost millions and would stir up a hornet's nest of airplane and engine recertification issues. Not to mention awakening the third rail of capitalism — product liability issues.
Questions have also been raised about the possibility of getting Congress to back off on ethanol mandates to guarantee a nationwide supply of ethanol-free premium grade auto gas for aircraft. Auto gas supplemental type certificates (STCs) by the Experimental Aircraft Association (EAA) and Petersen Aviation are invalidated if an airplane is fueled with auto fuel that contains ethanol.
Doug McNair, vice president of government relations at the EAA, said there's no political will in Washington to oppose ethanol mandates; in fact, Congress recently passed legislation mandating higher levels of ethanol in auto gas.
There is a growing consensus that a 100-octane replacement fuel of some kind is needed to replace 100LL.
"100 Octane," Says Lycoming and Cessna Jack Pelton, Cessna's chairman, president and CEO, boiled down the issues swirling around the search for an unleaded avgas in a November 2010 statement when he said, in part, "The key is to not leave anyone behind; the solution must be global and it must be technically and financially viable."
Pelton's "global" solution comment is important. U.S. airplane and engine manufacturers have been slowed in their attempts to expand into new markets by the leaded-fuel requirements of high-performance engines. 100LL is expensive outside the United States and is close to nonexistent in most developing regions of the world. The development of a new lead-free 100 octane avgas would be a boon for U.S. companies seeking expansion in today's emerging and largely untapped aviation markets.
The call for a 100 octane fuel was voiced by Kraft at Lycoming and echoed by John Bouma, manager of propulsion systems at Cessna. Kraft said that "we're going to get one chance in one grade" and urged all concerned parties to work together when he said, "We need to mobilize our resources and get on with it," during a speech at AirVenture 2010.
Kraft stressed how important it is to the industry to make a decision before AirVenture 2011 due to the long lead times needed to bring the new fuel to market.
Is Less Lead OK?
During a presentation at AOPA Summit in November 2010, Passavant discussed the EPA position in a 10-page PowerPoint presentation. Passavant also told the audience that "the law doesn't say there has to be zero lead — just that there has to be action."
One action that's endorsed by today's avgas providers is bringing very low-lead 100 octane avgas (100VLL) to the market. Since 100VLL can be produced today under D-910, the existing ASTM standard, this step would not require a large investment in infrastructure or time. Industry insiders all cited 100VLL as a viable interim step forward that would not only reduce lead emissions but would answer the EPA's call for action on the part of the industry.
The introduction of 100VLL would reduce lead levels. Would it prove to be an acceptable long-term solution to both greenhouse gas and lead concerns? Would politics play a role in easing mandates or making ethanol-free unleaded auto gas available? These questions are among those voiced every day on Internet chat rooms and aviation websites.
The more pressing concern for the future of the new avgas is demand. If the cost numbers provided by GAMI and Swift are realistic, flying would still be affordable for most of today's owners. And if the new avgas could be manufactured and transported using existing infrastructure, the odds of a smooth transition improve dramatically.
But if there isn't enough demand to provide a reasonable long-term return on the capital investment required to bring the new avgas formulations to market, the only viable solution may be 100VLL or engine modifications or a combination of the two.
Passavant left all options open when he said, "We want to move in an orderly, fact-based manner so that, when we make a determination of the data, there's a good fact-based process and a way forward to resolve it." Passavant added that the EPA "is thinking about the cost and the safety."




