Not to be left behind in the post-war jet revolution, the Grumman F9F Panther was the company's first major jet fighter to be operated by the US Navy and second only to the FH Phantom. The F9F was originally designed as a four-engined carrier-based fighter but testing with imported Rolls-Royce Nene engines meant that only one of these was necessary to power the new successor to the legendary Grumman 'cats'. Like most early jets, the F9F featured straight wings with wingtip fuel tanks which would be one of its main distinguishing features although swept wings would eventually be installed in the improved F9F Cougar which was otherwise nearly identical. A total of 24 USN and USMC squadrons were equipeed with the F9F during the Korean War where it was used mainly for ground attack althought it did achieve distinction by scoring the first naval kill of the war (a Yak-9) and the first jet vs jet combat of the USN when one shot down a MiG-15. The only export operator was Argentina while some Cougars would fly well until the Vietnam War as forward air controllers.

The XF9F-1 Panther had originally been designed with four Westinghouse J30 turbojets but these were replaced by the Rolls-Royce Nene in the XF9F-2 which first flew on 24 November 1947. Production versions began with the F9F-2 powered by a locally built version of the British engine while the F9F-3 used Westinghouse J33s which due to reliability issues were replaced. These were followed by the F9F-4 (J33) and -5 (Rolls-Royce Tay) of which the grand majority of the former ended up yet again with the Tay. A photo-reconnaissance version of the Panther was known as the F9F-2P. Next up was the XF9F-6 which first flew on 20 September 1951 and featured swept wings and the removal of the wingtip tanks (photo recon versions were known as the F9F-6P). Subsequent versions included the F9F-7 with J33 engines and the ultimate F9F-8 with a lengthened fuselage and modified wing (redesignated F-9J in 1962). Subvariants were the F9F-8P with cameras and the -8B (AF-9J) ground attack version with missile carrying capability. A two seat trainer was also known as the F9F-8T (TF-9J) and was the last to be retired from US Reserve units in the 1970s.