Will 100 LL fall to AGE85?

Researchers, pilots and private industry representatives address the pros and cons of AGE85 at Ethanol In Aviation Conference
By | June 01, 2002
Grand Forks, N.D. - If one conclusion had to be made about the Ethanol In Avaition Conference, held last month in Grand Forks, N.D., it was this: research and development of ethanol-based aviation fuel looks promising, but attaining certification, supply security, and industry acceptance is going to be a steep uphill climb.

That realistic outlook, according to industry experts, is undeniable because 100 low-lead (LL) aviation fuel (avgas) has been a stable, dependable piston-engine aircraft fuel for over a century, despite the fact that 100 LL is the only FAA-approved fuel in the U.S. still allowed to contain carcinogenic tetra-ethyl lead. In fact, avgas has four times more lead than was used in leaded automotive gasoline before it was banned from use in new cars in 1973. Nearly 30 years later, leaded avgas is still getting a free ride on the basis that it is the most economical method for achieving 100-octane fuel.

However, a growing number of researchers and environmentally conscience pilots, following in the footsteps of pioneer Max Shauck, of Baylor University, believe a high-octane ethanol-based fuel could - and should - eventually replace 100 LL.

To this end, researchers, pilots and private industry representatives gathered at the University of North Dakota School of Areospace in Grand Forks, May 21-22, to address the pros and cons of widespread use of ethanol-based aviation fuel. Specifically, the discussions were focused on the potential of AGE85, formulated at the University of North Dakota Energy & Environmental Research Center (EERC), and tested and certified by South Dakota State University in Brookings, Great Planes Fuel Development in Watertown, S.D., Lake Area Technical Institute in Watertown, and Texas Skyways of Boerne, Texas.

The Federal Aviation Administration (FAA) has certified the fuel, which is about 85 percent ethanol and contains a high-octane petroleum product, in addition to biodiesel for its lubrication and anti-corrosion properties. In flight tests and engine teardown inspections conducted in San Antonio, Texas, AGE85 was demonstrated to meet or exceed FAA performance, materials compatibility and engine component wear specifications. It was approved for use in several different models of Cessna aircraft equipped with Continental engines.

According to Great Planes Fuel Development Corp. President Jim Behnken, the engine wear observed following the mandated 500-hour endurance test was so minimal that the FAA has waived the test as a requirement in future AGE85 certifications for additional aircraft models.

The current avgas market in the United States alone is not huge: about 600-700 million gallons per year. It is an attainable market for AGE85, but the challenge lies in gaining acceptance in an industry that refuses to let go of lead.

Infrastructure challenges
"Unfortunately, the industry uses (tetra-ethyl) lead," said Phillips 66 executive J. Mark Wagner, who spoke at the conference. "We would like something to replace it, and the EPA would too. Believe me, we would all like to see lead go away, but that's not going to happen overnight."

Wagner, who said Phillips 66 is not going to "naysay" ethanol-based aviation fuel, cautioned the developers of AGE85 to be cognisant of the extensive challenges that lie ahead in terms of infrastructure, distribution, and supply. Phillips 66, which controls about one-third of the U.S. avgas market, ships its product nationwide by truck, rail, barge and pipeline. At any given time, Phillips 66 has enough 100 LL in storage to serve its distributers for up to six months, Wagner said.

"We have 75 years of trust built up (with 100 LL)," Wagner said. "I'm telling you that supply security is needed if (AGE85) is going to work."

100 LL will not last'
"100 LL aviaiton fuel will not last. . . its demise is coming," said William Schultz, a representative of the General Avaition Manufacturers Association.

That thought in mind, Schultz outlined the challenges that must be prioritized should a fuel such as AGE85 gain industry-wide acceptance.

"The entire general aviation industry is designed around 100 LL fuel," Schultz said. "If ethanol should come into acceptance, there will be extensive physical and operational modifications that will likely negate much of the current operation safety and reliabilty database. . . the fuel would have to be performance satisfied, attain function reliability and eventually be system certified with other products."

To achieve these enormous challenges, Schultz reccomended, the stakeholders of AGE 85 must work together, and with the owers and operators of general aviation airplanes.

"When you stand back and look at the big picture, there is an abscence of connectivity between the groups developing ethanol aviation fuels (and other stakeholders)," Schultz said. "These activities cannot be fragmented any longer. We must remember that whatever is decided, whatever is developed, there will be one fuel, so we need increased coordination immediately."

ASTM recognition

Ted Aulich, process chemist at UND's Energy & Environmental Research Center in Grand Forks, said AGE85 (or whatever ethanol-based avgas the industry chooses to accept) should be specified in conjunction with the American Society for Testing and Materials (ASTM). He said the process could take up to three years.

"It's important to get this recognition from ASTM," Aulich said. "This process would define the fuel, and (standardize) its chemical and physical properties and requirements."

Aulich also addressed an idea for denaturing ethanol without using gasoline. The standard ethanol denaturing process, used at virtually all ethanol plants, would fall below the standards used for fuel in the aviation industry. Therefore, Aulich proposes that ethanol used for avgas be denatured with pentane isomerate in place of unleaded gasoline. His idea seemed to be well recieved at the conference.

Approval & acceptance

A panel composed of Federal Aviation Administration (FAA) Fuel Specialist Mark Rumizen, Expirimental Aircraft Association (EAA) Vice President Earl Lawrence, Lycoming Senior Installation Engineer Dan Fletcher, Coordinating Research Council representative Ron Wilkinson, and Aviation Owners and Pilots Association spokesperson Andrew Werking, together presented a composition of ideas and opinions about ethanol's chance of gaining acceptance in the aviation industry. The outlook was mixed at best.

"The FAA is not pessimistic, nor optimistic, about (ethanol-based avgas)," Rumizen said. "We are an emotionless regulator."

Werking, who said he is optimistic about ethanol, said the developers of AGE85 need to prove to prospective buyers that the fuel is safe, compatible with standard engines and equipment, and economically viable.

"You're facing unprecedented challenges," Fletcher told AGE85 proponents. "Even with (ASTM specifications), there are still no guarantees that anyone is going to rush out and use ethanol in their planes."