Swift Fuel Runs an R-2800 Radial
October 27, 2011 – More than 100 gallons of Swift Enterprises' 100SF powered an unmodified Pratt & Whitney R-2800 Double Wasp engine during three days of testing conducted in Grangeville, Idaho. Test results showed that 100SF produced a higher detonation onset threshold than 100LL. The engine was operated at 115-145 octane takeoff power settings and there were no indications of engine knock.
Anderson Aeromotive Inc. conducted the informal round of testing the high-octane, unleaded, sustainable aviation gasoline in an unmodified World War II-era radial engine. Ron Adams, performance lead at Swift Enterprises, said the tests were conducted to evaluate 100SF's ability to meet the needs of pilots who fly critical missions using large radial engines.
"Some remote communities in Alaska and other areas of the world are inaccessible by ground transportation, and they depend on aircraft powered by large radial engines to bring essential supplies," he said. "To date, these engines posed a significant barrier for any alternative aviation fuel because they demand high-octane gasoline to produce their design horsepower. We wanted proof that 100SF can shatter that barrier."
Norman Koerner, president of TriCap International Inc., was the catalyst needed to make the testing possible. Koerner has had a longtime interest in flying aircraft with large radial engines and knew the leaded fuel needed to operate large radials was under scrutiny.
"Learning that Swift Enterprises and Anderson Aeromotive shared this concern, it was natural to arrange the initial testing that has now proven that 100SF is most definitely a candidate for further testing," he said.
100SF will undergo another, more intense and formal round of radial engine testing in 2012 as funding becomes available. Tri-Cap International will be the lead, but the date and location are yet to be confirmed.
"The next phase, which will include further detonation, ADI, and pressure carburetor work, will pave the way for commercial operators of legacy aircraft - who burn more than 10 percent of the avgas used in the United States - to continue providing their essential service," Koerner said. "Additionally, 100SF will be able to power the heritage aircraft that are indispensible in preserving the history of World War II. I think it's the right thing to do, so let's keep 'em flying!"