||Dryden's F-16XL-1 aircraft (tail number 849) testbed aircraft supported several flight research projects during the 1990s. The XL-1 aircraft was upgraded with a new Digital Flight Control System (DFCS) in 1997. The DFCS upgrade allowed NASA's F-16XL-1 the flexibility needed to perform experiments which required major new flight control functions or capabilities.
Previously, the aircraft was used in a program to investigate the characteristics of sonic booms for NASA's High Speed Research Program. During the series of sonic boom research flights, the F-16XL was used to probe the shock waves being generated by a NASA SR-71 and record their shape and intensity. Data from the program could be used in the development of a high speed civilian transport.
The F-16XL aircraft were built by General Dynamics Corp. as prototypes for a derivative fighter evaluation program conducted by the Air Force between 1982 and 1985. The aircraft were developed from basic F-16 airframes. The most notable difference is the delta (cranked arrow) wing which give the aircraft a greater range because of increased fuel capacity in the wing tanks, and a larger load capability due to increased wing area.
The single-seat F-16XL aircraft is powered by a Pratt and Whitney 100-PW-100 engine (with afterburner), rated at 23,830 pounds thrust, and features an analog fly-by-wire electronic flight control system. The delta (cranked arrow) wings on both aircraft provide strength for high wing loads during flight. The aircraft's dimensions are; length, 54.2 feet (16.52 m); wingspan, 34.3 feet (10.45 m); height at vertical tail, 17.7 feet (5.39 m). The aircraft's maximum weight is 48,000 pounds (17915.60 kg), has a design load of 9 "Gs" (In the research configuration, 3 "Gs"), and has a top design speed Mach 1.8.