XWF-1 Tracer

The Grumman XWF-1 Tracer was a pioneering experimental jet developed in the early 1970s as part of the United States Navy’s effort to explore high‑speed, low‑observable strike concepts. Ordered in 1971, the prototype first flew on 12 June 1974 from the Naval Air Station Patuxent River and served for five years of intensive testing before being retired in 1979. Built around a lightweight composite airframe, the Tracer employed a low‑aspect‑ratio delta wing and integrated inlet‑airflow shaping to reduce radar cross‑section, making it one of the earliest attempts at stealth in a carrier‑based platform. Its General Electric J85‑P-15 turbojet delivered 4,300 lbf of thrust, enabling supersonic cruise at Mach 1.8 while maintaining a service ceiling of 55,000 feet. The aircraft featured fly‑by‑wire controls, a digital flight‑control computer, and an innovative modular avionics suite that could be swapped for research payloads. Although the XWF‑1 never entered production, its flight data influenced the design of later Grumman projects such as the F‑14 Tomcat’s upgraded radar and the Navy’s eventual adoption of low‑observable technologies. The Tracer’s legacy endures as a critical stepping stone toward modern stealth fighters and unmanned combat air vehicles.