The Republic F-84F Thunderstreak is an American swept-wing turbojet-powered fighter-bomber. The RF-84F Thunderflash is variant of the F-84F that was designed for photo reconnaissance.

The design was originally intended to be a relatively simple upgrade to the F-84 Thunderjet to make it more competitive with the F-86 Sabre, differing largely in the use of a swept-wing and tail. Given the small number of changes, it was assigned the next model letter in the F-84 series, F. The prototypes demonstrated a number of performance and handling issues, which resulted in marginal improvement over the previous versions. Production was repeatedly delayed and another run of the straight-wing Thunderjets were completed as the G models.

Looking for a clear performance edge compared to the G models, the engine was upgraded to the much more powerful British Armstrong Siddeley Sapphire built in the United States as the Wright J65. The larger engine required the fuselage to be stretched into an oval shape and the air intake to be modified. With these and other changes, the design was finally ready to enter production, but only a fraction of the original production systems could be used and the aircraft was effectively a new design. It finally entered service in November 1954, by which time the Sabre had also undergone many upgrades and the Thunderstreak was relegated to the fighter-bomber role. Its time as a front-line design was brief; it began to be moved to secondary roles as early as 1958.