The Granville Gee Bee R-6 International Super Sportster, named "Q.E.D." (latin: quod erat demonstrandum "it is proven"), and later named "Conquistador del Cielo" (Spanish: "sky conqueror"), was the last in a series of racing and touring monoplane aircraft from the Granville Brothers. The R-6H was dogged with bad luck throughout its career and never finished any race it entered.