The FL1 Sparrow is a single-engine, two seat jet fighter designed by Leviathan-Automobile Aero-Division.
The FL1, or Fighter, Light, Model 1, was the first standardized Expression 2-powered, ACF-armed jet fighter to be operated by the LERAF. The first models of this aircraft were unsuccessful and saw little combat, then retired from service after the FL4 was introduced. Following the failure of the FL4 project, the LERAF pulled the FL1 from retirement and began a modernization program, the results of which are the FL1B and FL1C.
The FL1B was upgraded to carry two air-to-air missiles, new gun systems, new internal electronics, as well as improved exterior and interior features. Shortly after, the FL1C model began production, which saw the addition of two more wing hardpoints for attaching additional missiles or bombs.
The first FL1 models had little to no success. The FL1B/C models, with their air to air missiles and better control systems had reasonable success against other similar planes.