The famous Howard DGA-6 Replica “Mister Mulligan” became the first airplane in history to use GAMI G100UL high octane unleaded avgas in an airshow performance April 10, 2024 at Sun ‘n Fun in Lakeland, Florida. “Mister Mulligan” was built in 1934 and was an aviation pioneer in the Golden Age of Air Racing. The replica airplane, flown by Doug Rozendaal, pioneered the first use of G100UL fuel in an airshow performance 90 years later. “Mister Mulligan” is powered by a Pratt and Whitney R-1340 engine. Rozendaal also has flown with G100UL in his 10-1 compression Lycoming powered TRF-1 Rocket. Doug has this to say about G100UL fuel,

In both aircraft there were no operational differences between G100UL and 100LL fuel. Fuel flows were slightly lower and EGTs slightly higher, but imperceptible without modern engine monitoring. Based on my experience I believe G100UL is a suitable drop-in replacement for 100LL fuel.

The result of over a decade of painstaking fuel research and certification work, GAMI’s G100UL high octane unleaded avgas is a functional drop-in replacement for 100LL avgas that maintains or improves engine performance and, simultaneously, significantly reduces routine maintenance costs imposed by use of leaded avgas. On September 1st, 2022, the FAA approved the use of G100UL Avgas in all spark ignition piston engines in the FAA’s type certificate database, and all the airplanes that use any of those engines. Specifically, that includes all very high-powered engines used in the legacy fleet of classic WWII aircraft. On April 10th, at the Sun and Fun Airshow, GAMI and Vitol Aviation announced that Vitol had produced a 1.2-million-gallon tank of G100UL Avgas and that G100UL Avgas was now commercially available.

”Mister Mulligan” is owned and flown by Doug Rozendaal, a highly experienced, long-time, warbird and airshow pilot based in Clear Lake, Iowa. Rozendaal holds a surface level aerobatic waiver in several WWII fighters, Sport aircraft and is an FAA Designated Specialty and Vintage Pilot Examiner. He also owns and operates PetroBlend Corp, a Petroleum and Chemical Company and the manufacturer of Pure White Smoke Oil in Mason City, Iowa.

General Aviation Modifications Inc. (GAMI) is a small innovative general aviation company located at the Ada Municipal Airport, in Ada, Oklahoma. GAMI and sister company Tornado Alley Turbo, Inc., are famous for their innovative general aviation technological inventions and related FAA approvals. Those innovations include their GAMIjector® Fuel Injectors, and over three thousand Bonanza, Cirrus, and Cessna aircraft modified with their turbo-normalizing turbocharger systems.