Can GA get the lead out?

June 12, 2008

AOPA is telling the Environmental Protection Agency (EPA) that any immediate changes to current aviation fuel standards to remove lead would have a “direct impact on the safety of flight and the very future of light aircraft in this country.”

Testifying on June 12 in Baltimore before an EPA hearing on air quality standards for lead, AOPA Executive Vice President of Government Affairs Andy Cebula said, “The aviation industry shares the concern about lead in the environment. The general aviation community is actively researching alternative fuels, and we’re developing certification standards for new fuels and engines. But despite a decade of research and trials, there is currently no unleaded alternative for 100LL avgas that can be used safely by all piston-powered aircraft flying today.”

That’s because tetra ethyl lead (TEL) is the only available fuel additive approved and proven to protect high-performance aircraft engines from detonation. That detonation can literally tear apart an engine in flight. Other octane enhancers, such as ethanol, can adversely affect aircraft engines and systems. In fact, current FAA standards prohibit the use of ethanol in aircraft fuel systems.

But that doesn’t mean that the industry is not searching for a lead replacement. In the 1970s, aviation transitioned to a fuel (100LL) that contained half the lead of the previous aviation gasoline standard. AOPA continues to work with petroleum producers, researchers, and others to develop alternative fuels and engine technologies under the auspices of the Coordinating Research Council. And the association has lobbied for continued funding for the FAA’s research into unleaded fuels at the William J. Hughes Technical Center.

Cebula noted that avgas is literally a drop in the bucket when compared to fuel consumed in the United States. Aviation gasoline makes up only 0.25 percent of all petroleum products. The nation’s drivers burn more auto gas in one day than general aviation uses in a full year. And avgas usage has declined some 18 percent in the last five years.

That very small volume means that only one fuel, suitable for all piston-powered aircraft, can be economically viable. “A suitable unleaded replacement fuel is one that can be used in all existing and new piston-powered general aviation aircraft,” Cebula told the EPA. “AOPA understands that for a small percentage of aircraft, this may require engine and airframe modifications.”

“Lowering the national ambient air quality standards for lead, without a suitable replacement fuel available, would negatively affect the $150 billion general aviation industry, threatening a nationwide transportation system that supports smaller communities, agriculture, firefighting, and medical emergency flights,” said Cebula. “Reducing the amount of lead in avgas is not a simple process. The EPA needs to consider the dramatic impact it could have on general aviation and the nation’s economy if it were to make immediate changes in the lead standard.”