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AOPA President Mark Baker flew in a Beechcraft Baron twin-engine on Oct. 31 using the first 100-octane unleaded formula to gain an FAA supplemental type certificate. For the demonstration, the unleaded fuel went into the left wing to feed the left engine and leaded gas went into the right wing to feed the right engine, closely comparing the two engines operating concurrently on the same airframe to eliminate possible variables while evaluating the different fuels.
The flight demonstration began on Oct. 31 in a Beechcraft Baron twin (N202MD) in Ada, Oklahoma where General Aviation Modifications Inc. produces the G100UL. Future flight demonstrations will be scheduled and GAMI is working toward the commercialization of its fuel to distribute it more widely across the nation. The AOPA intends to demonstrate other 100-octane unleaded fuels as they become available.
"We want to get some actual experience with 100 octane unleaded fuel in the kinds of airplanes and engines that our members own and fly," Baker said. "This fuel has been tested extensively in labs and received an STC. Should the FAA authorize additional fuels, we'll test them, too, so we can see what they're like to use out on the airways."
The AOPA is leasing a recently refurbished 1966 Beechcraft Baron C55 from Greg Herrick of Wyoming for $1 each year in order to monitor the unleaded fuel demo, which is expected to last up to two years. Donor Dan Shewmaker will be offsetting the operational costs. The plane is equipped with two freshly overhauled and non-turbocharged Continental IO-520 engines. The Beechcraft Baron is equipped with Garmin avionics including an engine monitor capable of recording a range of engine data. By comparing the two engines operating at the same time and on the same airframe, the AOPA is determined to eliminate as many variables as possible while evaluating different fuels, relaying findings to members through the AOPA media channels.
Baker is a Baron owner and pilot. He traveled to Ada and flew the demo Baron for one hour with G100UL feeding the left engine and 100LL feeding the right. Baker said the performance of the two engines was nearly identical. The flight also included numerous full-power takeoffs and a prolonged high-power cruise at over 75 percent power.
"George Braly and GAMI have done a great deal of pioneering work preparing for general aviation's unleaded future," Baker said. "We're bringing the AOPA Baron to GAMI's headquarters in Ada, Oklahoma, first to try out its G100UL."
The plane's engines will undergo regular borescope inspections and compression tests to compare the internal engine wear. Founder of Savvy Maintenance and AOPA Pilot magazine columnist Mike Busch will analyze the engine data collected using Savvy's computerized diagnostic tools. Savvy gathered detailed engine data from hundreds of thousands of hours of GA flights and has developed a predictive diagnostic tool to anticipate engine component failure before it takes place.
"We look forward to taking a close look at the data AOPA collects," Busch said. "The fact that it's being gathered from two engines on the same airframe makes it particularly interesting."
The demo Baron has logged about 3,700 flight hours from when it was first manufactured to the early 2000s. The owner, Herrick, is a vintage plane collector and restorer. Herrick bought the Baron in 2010 and it has been mostly inactive over the last five years. With Herrick's funding and AOPA's management, the Baron underwent recent maintenance including the reconditioning of the fuel bladders, engine and Hartzell prop overhauls, and replacing and rerigging some landing gear components. AOPA staff pilots then ferried the plane from Minnesota to Pennsylvania, to Virginia for upgrades. Upgraded and updated, the Baron is ready to start logging hours using unleaded fuel and delivering results to GA pilots.
This demo flight took place just weeks after the EPA released its final determination that lead emissions from aircraft cause or contribute to air pollution that may endanger public health and welfare. This determination has begun the multi-step process to transition aviation to unleaded fuel, a process which was well underway before the determination. Airports across the country are approving the use of alternative fuels like SAF and unleaded fuels, and testing like this flight demo is bringing the aviation industry closer to its goal of eliminating lead from gas by 2030 and achieving net-zero carbon emissions industry-wide. Aviation stakeholders are in favor of the switch but advocate for extensive testing and time to safely transition to unleaded fuel.RELATED STORY:EPA determines leaded fuel endangers public health, aviation coalition responds
"The move to unleaded fuel is absolutely critical to the future of general aviation," Baker said. "This airplane is a valuable tool because it can help us make the transition safely and confidently."