The Grumman XF10F Jaguar was a prototype swing-wing fighter aircraft offered to the United States Navy in the early 1950s.
Although it never entered service, its research pointed the way toward the later General Dynamics F-111 and Grumman’s own F-14 Tomcat.
The Navy’s interest in the variable-geometry wing was based on concerns that the ever-increasing weight of its jet fighters was making aircraft carrier operations troublesome.
Many of its existing aircraft already had marginal carrier performance, and the trend in weight growth was obviously upward.
At the same time, the demands for high-speed performance demanded swept wing layouts that did not lend themselves to good take-off characteristics.
The prospect of combining the two in a single aircraft was enticing.
Originally conceived as a swept-wing version of the earlier F9F Panther, in February–March 1948, the design was reconfigured with a T-tail and ultimately a variable-geometry wing.
It featured a T-tail, with the horizontal stabilator, a small pivoting centre body with a delta servo control at the nose and a larger rear delta main wing, mounted atop the vertical fin.
The single turbojet engine was fed by cheek intakes.
The high, shoulder-mounted wing could be moved to two positions: a 13.5° sweep for take-off and landing and a 42.5° sweep for high-speed flight.
The unique horizontal stabilizer design was free-floating; the attached small foreplane was directly controlled by the pilot and pulled the stabilizer up or down; so, it was aerodynamically, not mechanically controlled, and this resulted in sluggish pitch control, increasingly so at low speeds where airflow over the small foreplane was lessened, and if the project had developed further, it probably would have been replaced by a conventional all-flying tailplane.
The unpredictable behaviour of the design often caused pilot-induced oscillations, with the sudden and erratic deployment of leading-edge slats causing the aircraft to be nearly uncontrollable much of the time.
The XF10F-1 was not armed, but production aircraft would likely have had four 20 mm (.79 in) cannon and pylons for bombs and rockets, like other contemporary Navy fighters.