Staff Writer (Updated: 6/3/2016):
Consistent across all of the Grumman carrier-borne offerings were folding wings, tail arrestor hooks and reinforced undercarriages - as well as the "cat" name. The F11F Tiger began as a private venture endeavor on the part of Grumman in 1952, building upon the F9F Cougar which was, itself, a swept-wing form of the original F9F Panther fighter. The Panther managed combat service in the Korean War (1950-1953) as a ground attack jet platform so it provided the proven pedigree. The primary goal was to produce the smallest possible airframe around a rather powerful turbojet installation with the intend being a high-speed aerial combat mount principally to counter emerging Soviet fighter threats of the period.
Grumman undertook its new supersonic initiative as the "Model G-98". This mated a tubular, aerodynamically refined fuselage with mid-mounted swept main wing assemblies and swept tail planes (all-moving). A portion of the main wings were also hinged to fold downwards for storage on the space-strapped American carriers. Folding was accomplished manually so no expensive and complicated powered hinged systems were required. There proved a single vertical rudder and two side-mounted intakes aspirating the single turbojet engine within. The powerplant of choice was the Wright J65 turbojet engine (the license-produced British Armstrong Siddeley Sapphire) buried in the center-aft portion of the fuselage. The undercarriage was a tricycle arrangement with two single-wheeled main legs under the fuselage and a twin-wheeled nose leg at front. The cockpit was fitted well-forward in the design with a two-piece canopy and light framing. Despite its origination in the Cougar, the G-98 became an all-new aircraft design after the substantial changes were implemented.
Grumman then presented its new design to the United States Navy which elected to order a pair of prototypes under the "XF9F-8" designation (note the F9F Panther/Cougar connection in the designation). When the upcoming F9F "Cougar" was formally fleshed out, that particular design was handed the XF9F-8 designation and the new Grumman concept became the "XF9F-9". Construction of G-98-based prototypes then proceeded with the first prototype recording its initial flight on July 30th, 1954. As the J65 afterburning engine was not yet ready for prime time, the XF9F-9 went airborne with a more modest, non-afterburning powerplant yet still managed a solid presentation, proving the airframe sound. The new aircraft was then bestowed the formal USN designation of F11F "Tiger" in April of 1955 with initial production models to arrive as "F11F-1". The first USN carrier to receive an F11F was the USS Forrestal though this during the requisite carrier trials. Development of the F11F was, for the most part, fraught with delays and tribulations - a lower-powered turbojet was eventually adopted for production quality aircraft simply to bring the Tiger into operational service rather than extend its expensive development cycle.