Even as the straight-winged F9F "Panther" was beginning to take shape on the design board during the latter stages of World War 2, Grumman looked to developing a swept-wing jet-powered fighter. Swept-wings were already in operational service with German jet-powered aircraft late in the war, such as the famous Messerschmitt Me 262 fighter, and German scientists were hard at work in pushing the boundaries of high-speed flight even into the last days of the conflict. Turbojet technology was being studied extensively during the period throughout Germany, Britain, the United States and the Soviet Union with only the British and the Germans bringing an operational-level quality fighter into service before the end of the war in 1945.
For the Grumman concern, who eventually earned the favor of the United States Navy when selling its collection of excellent fighter types - from the World War 2-era F4F "Wildcat" and F6F "Hellcat", to the Cold War-era F-14 "Tomcat" - the F9F "Panther" proved its first jet-powered fighter and the first such notable aircraft to the USN. The series went on to see extensive service throughout the Korean War (1950-1953) as a ground attack platform while scoring several air-to-air kills even against the famed Mikoyan-Gurevich MiG-15 "Fagot" swept-wing, single-seat fighter. The Panther formed a good portion of USN and USMC strength committed to the theater of war.
A swept-wing version of the F9F Panther was conceived in what would ultimately emerge as the F9F "Cougar" - the natural evolution of the Panther for it retained the same overall physical appearance of the former design, the major difference becoming its new swept-back wing design. While studies of such an aircraft were being drawn up as early as December 1945, it was not until March of 1950 that the USN officially commissioned Grumman with its development. Considering the success of the straight-winged Panther in the Korean War, the Cougar could be developed along much quicker lines around the already-proven airframe utilizing the same technology within. Grumman was handed the USN contract in March of 1951 and, by this time, the USN was firmly entrenched in Korea where its Panther would go on to record over 78,000 sorties in the conflict. The arrival of the swept-wing, Soviet MiG-15 fighter only spurred greater American military interest in similar swept-wing fighters which ultimately culminated in the war-winning North American F-86 "Sabre" series detailed elsewhere on this site.
Original Panthers were selected for modification and had swept-wing surfaces installed at their main spars and at the tail rudder. First flight of a modified Panther was achieved on September 20th, 1951. Each wing was given a sweep of 35 degrees and, unlike original Panthers, the prototype form lacked the wingtip fuel tanks. The new aircraft only retained the main-forward portion of the Panther's fuselage while the wings and some of the empennage were of largely new design. Wing roots were lengthened though retaining similar triangular intakes as on the Panther. These split intakes aspirated the single engine within and exhausted jointly through a single cylindrical exhaust port under the tail. The canopy carried the same "tear-drop" shape which offered excellent vision out of the cockpit. The single rudder assembly now showcased a pair of high-mounted, swept-back horizontal tail surfaces to complete the new appearance. The undercarriage remained retractable and featured two single-wheeled main legs and a single-wheeled nose leg. A tailhook was fitted under the tail which allowed for the requisite aircraft carrier-landing capabilities. The powerplant of choice became the Pratt & Whitney J48 series turbojet which also powered later Panther variants (F9F-5). With a special water/alcohol injection system, the aircraft could manage a thrust output of 7,250lbs.
Even as the Panther was already entrenched in the USN inventory by 1950, the service elected to procure the more modern F9F Cougar in some number - 1,392 in all. Its similarities and pedigree to the preceding Panther also led to the "F9F" designation being used by the USN for its newer Cougar line. The US Navy took on their first stock of Cougars in the latter part of 1952 as the "F9F-6" since the related F9F Panther variants ended at the "F9F-5" designation.
The Cougar line was born through three completed prototypes constructed and tested under the "XF9F-6" designation. Initial production models - the F9F-6 - totaled 646 examples. The F9F-6P was a dedicated photographic reconnaissance version sans its cannon armament and produced across 60 units. The F6F-6D was a "drone director" modified from retired F9F-6 production mounts. Drone directors born from F6F-6P recon models then became F9F-6PD. Retired F9F-6 fighters were also used as unmanned target drones under the F9F-6K designation, improved versions appearing as F9F-6K2.
Some 168 examples of the newer F9F-7 variant were produced and these were powered by the Allison J33 series turbojet engine which promoted a thrust output of 6,350lbs. However, many of these aircraft were eventually re-engined to take the standardized PW J48 turbojet in time as the J33 failed to make a wholly positive impression in practice.
The final (and definitive) Cougar variant became the F9F-8 which saw its fuselage lengthened and wing surface area increased. An in-flight refueling probe was added as was provision for 4 x AIM-9 "Sidewinder" short-ranged, air-to-air missiles. Its prototype first went airborne in December of 1953 and exceeded the speed of sound during a controlled shallow dive in January of the following year. The F9F-8 was produced in 601 examples with first deliveries beginning in April of 1954 and concluding in March of 1957. One version was further developed into prototype YF9F-8B which became the start of a dedicated single-seat attack platform. From this was formed the F9F-8B which were converted F9F-8 mounts intended for the ground attack role.
The F9F-8 was powered by a Pratt & Whitney J48-P-8A turbojet engine of 7,200lbs thrust. Performance specifications included a maximum speed of 650 miles per hour, a service ceiling of 50,000 feet, an operational range of 1,000 miles and a rate-of-climb nearing 6,100 feet per minute. It featured a standard armament array of 4 x 20mm M2 cannons and could support up to 2,000lbs of underwing ordnance (2 x 1,000lb bombs or 6 x 5"/127mm rockets). Wingspan measured 34 feet, 6 inches with a fuselage length of 44 feet, 5 inches and a height of 12 feet, 3 inches. Weights included a listed 11,866lbs when empty and 24,760lbs maximum take-off-weight.
The F9F-8 line also spawned the requisite unarmed photographic reconnaissance model in the F9F-8P of which 110 examples were delivered. The F9F-8T became a two-seat trainer born from the YF9F-8T prototype based on the F9F-8 model. The USN procured 377 of these trainers from 1956 to 1960 to which many soldiered on longer than their single-seat fighter counterparts, some not retired until 1974. Two NTF-9J marks served as specialized test aircraft.
Due to the 1962 US aircraft designation restructuring, designations of Cougars followed suit and F9F now became "F-9F". Similarly, the F9F-6D drone director became the DF-9F and the F9F-6K unmanned drone forms became the QF-9F.The F9F-7 became the F-9H after 1962 and the F9F-8 was redesignated to F-9J. F9F-8B models became the AF-9J and F9F-8T trainers were redesignated to TF-9J.
The Argentine Navy joined the US Navy and USMC in operation of the F9F Cougar (as it did with the F9F Panther prior). It was Argentina's first jet-powered aircraft to break the sound barrier. The country was the only export operator of the Cougar line.
The F9F Cougar arrived too late to see combat actions over the Korean peninsula during the Korean War (1950-1953). While available to some degree during the Vietnam War years (1955-1975), no single-seat Cougars were deployed to the theater - only four two-seat TF-9J trainer variants given the charge. Retaining their combat capabilities, these aircraft were deployed to Southeast Asia and used in airstrike directing for incoming allied warplanes.
As the F9F Cougar was evolved from the existing F9F Panther line, the Cougar, itself, was also evolved into the YF9F-9 prototype which became the YF11F-1 and, ultimately, the F11F "Tiger" carrier-based fighter for the US Navy, serving from 1956 to 197. Along with Vought F8U Corsairs, F11F Tigers directly replaced outgoing F9F Cougars into the 1960s though production only totaled 200 units from 1954-1959.