, early 1980s, a predecessor of STOL/MTD program In 1975,
Langley Research Center began to conduct sponsored programs studying two-dimensional thrust vectoring nozzles; has flown several times since the successful STOL/MTD program completion in 1991 that used thrust vectoring and
canard foreplanes to improve low-speed performance. This aircraft tested high-tech methods for operating from a short runway. This F-15 was part of an effort to improve ABO (Air Base Operability), the survival of warplanes and fighting capability at airfields under attack. The F-15 STOL/MTD tested ways to land and take off from wet, bomb-damaged runways. The aircraft used a combination of reversible engine thrust, jet nozzles that could be deflected by 20 degrees, and canard foreplanes. Pitch vectoring/reversing nozzles and canard foreplanes were fitted to the F-15 in 1988. The canard foreplanes were derived from the
F/A-18's
stabilators. • A 25-percent reduction in takeoff roll
Further modifications During the 1990s the same F-15 airframe (USAF S/N 71-0290) was further modified (canards and nozzles were retained) for the ACTIVE ("Advanced Control Technology for Integrated Vehicles") program in which the Pratt & Whitney Pitch/Yaw Balance Beam Nozzles (P/YBBN) and advanced control-logic programming were investigated; NASA acquired the plane in 1993 and replaced the engines with Pratt & Whitney F100-229 engines with P/YBBN. In the ACTIVE configuration it was also used for the LANCETS ("lift and nozzle change effects on tail shock") program, in which computed supersonic
shockwave parameters were compared to those measured in flight. The LANCETS flight tests ended in December 2008. F-15 ACTIVE lasted from 1993 to 1999, with thrust vectoring demonstrated at up to Mach 1.95 on 31 October 1996. The aircraft would later be used in the F-15 IFCS (
Intelligent Flight Control System) program from 1999 to 2008. The airplane was also used for the Space-Based Range Demonstration and Certification project under the Exploration Communications and Navigation Systems program (SBRDC/ECANS) from 2006 to 2007, High Stability Engine Control (HISTEC) program, and High-Speed Research Acoustics in 1997. ==Specifications (F-15 ACTIVE)==