The YF-19 was a joint project between Lockheed Martin and NASA, developed in the early 1990s. It was designed to be a highly maneuverable and high-performance fighter jet, with a top speed of Mach 1.5 and a range of over 1,000 miles. The YF-19 was equipped with two afterburnering jet engines, as well as modern avionics and sensors.

The YF-19 was not as stealthy as fifth-generation fighters, but it was still a very capable aircraft. It was able to outmaneuver most other fighters of its time, and its avionics and sensors gave it a significant advantage in combat.

The YF-19 was never produced in large numbers, but it did serve as a testbed for many new technologies. These technologies were later incorporated into other fighters, such as the F-22 Raptor and the F-35 Lightning II.