: Although the 1979 Brazilian Grand Prix at Interlagos was held in February, Emerson Fittipaldi was forced to use the older F5A chassis there because the F6 was not yet race-ready; the F6 finally debuted later that year at the South African Grand Prix. Available Documentation
: A history of the team's engineering, including their use of Hewlett-Packard computers for testing at Interlagos, can be found in the Fittipaldi Years Archive on Speedfreaks.org. : Although the 1979 Brazilian Grand Prix at
: Testing at Interlagos and other circuits revealed that the chassis lacked sufficient rigidity—often described as "folding" or "bending" under load. These structural failures led the team to temporarily revert to the older F5A for many races while the F6 was extensively rebuilt into the F6A . : Although the 1979 Brazilian Grand Prix at