page_title: Granville Gee Bee R-6
section_title: Design
hierarchical_section_title: Granville Gee Bee R-6 / Design
caption_attribution_description: English: Catalog #: 01_00091524 Title: Gee Bee, Q.E.D. Corporation Name: Granville Brothers (Gee Bee) Designation: Q.E.D. Additional Information: USA As flown by the Mexican air hero, Francisco Sarabia. Repository: San Diego Air and Space Museum Archive
context_page_description: The sole Granville Gee Bee R-6 International Super Sportster, named "Q.E.D." Quod Erat Demonstrandum, and later named "Conquistador del Cielo", 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 had the unfortunate distinction of never finishing any race it entered.
context_section_description: The Gee Bee R-6 shares the same general shape and overall design as the better known Granville Gee Bee R-1 Super Sportster racer, but was nearly 10 ft (3.0 m) larger in span and length. 
  As built the aircraft was powered by a 675 hp (503 kW) Pratt & Whitney Hornet 9-cylinder air cooled radial engine enclosed in a NACA cowling. 
  The wings were built around a pair of spruce spars, with the front spars split into upper and lower beams while the rear spars were a single beam. Ribs were also spruce, and the entire wing was skinned with plywood and braced to the fuselage and undercarriage with streamlined wires. Split flaps that functioned somewhat similar to Zap flaps with an extra hinge line mid-chord were installed between the ailerons and the fuselage. After problems with these during the MacRobertson Air Race, they were redesigned without the extra hinge.
  The fuselage form followed an ideal teardrop shape calculated to minimize drag and was built up from welded chromium-molybdenum alloy steel tubes with plywood formers and spruce stringers. This was then covered with sheet aluminium panels forward, and fabric covering aft. The fin was integral with the fuselage structure, while the rudder and cantilevered elevators were constructed in a similar manner to the wings with a plywood covering. Tandem cockpits provided space for two under an extended greenhouse canopy.
  Although most contemporaries were already moving to retractable undercarriage, the R-6 persisted with the spatted and faired units common to their previous designs, although to save time, the actual gear legs were borrowed from the Curtiss A-12 Shrike.
caption: R-6H XB-AKM Conquistador del Cielo showing the later simplified flaps
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