Overview: The Grumman F9F Panther is one of the United States Navy's first successful carrier-based jet fighters, as well as Grumman’s first jet fighter. A single-engined, straight-winged day fighter, it was armed with four 20 mm (0.79 in) cannons and could carry a wide assortment of air-to-ground munitions. The Grumman F9F/F-9 Cougar was a carrier-based fighter aircraft for the United States Navy and United States Marine Corps. Based on Grumman's earlier F9F Panther, the Cougar replaced the Panther's straight wing with a more modern swept wing. Thrust was also increased with the installation of a newer, more powerful engine. The Navy considered the Cougar an updated version of the Panther, despite having a different official name, and thus Cougars started off from F9F-6.