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First supersonic yaw vectoring flight for ACTIVE program

April 24, 1996

Release: 96-25

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On Wednesday, April 24th, the F-15 Advanced Control Technology for Integrated Vehicles (ACTIVE) aircraft achieved its first supersonic yaw vectoring flight at Dryden Flight Research Center, Edwards, CA. ACTIVE is a joint NASA, U.S. Air Force, McDonnell Douglas Aerospace (MDA) and Pratt & Whitney (P&W) program. The team will assess performance and technology benefits during flight test operations. Current plans call for approximately 60 flights totaling 100 hours.

"Reaching this milestone is very rewarding. We hope to set some more records before we're through," stated Roger W. Bursey, P&W's pitch-yaw balance beam nozzle (PYBBN) program manager.

A pair of P&W PYBBNs vectored (horizontally side-to-side, pitch is up and down) the thrust for the MDA manufactured F-15 research aircraft. Power to reach supersonic speeds was provided by two high-performance F100-PW-229 engines that were modified with multi-directional thrust vectoring nozzles.

The project manager for Dryden, Don Gatlin, said that "this program is an example of government and industry cooperating to bring an important technology to maturity. Benefits derived from thrust vectoring for future aircraft include extended range, increased maneuverability, reduced operating cost and improved safety.

For NASA's flight research, each nozzle is mounted to one of the F-15 ACTIVE's two F100-PW-229 engines, which have modified fan duct cases to provide the additional strength required to withstand the vectoring forces. Installation of the nozzles also required modifications to the aircraft's rear fuselage and main engine mounts.

The new concept should lead to significant increases in performance of both civil and military aircraft flying at subsonic and supersonic speeds. Another important feature is the nozzles' production-oriented design, which would require minimal changes to be incorporated into current or future aircraft. An axisymmetric, or round, nozzle, the PYBBN provides up to plus or minus 20 degrees vectoring in any direction. The balanced beam concept, which has been proven in service in F100 convergent-divergent exhaust nozzles, minimizes control actuation loads and reduces the need for heavy, reinforced structures.

The nozzle features a fail-safe dual redundant actuation system, making it compatible with single-engine, as well as twin-engine, applications. The PW-229 with a similar pitch-yaw vectoring nozzle has been selected for integration into a modified F-16D in the U.S. Air Force's Variable-stability In-flight Simulator Test Aircraft (VISTA) program.

P&W's Government Engines & Space Propulsion unit designs, develops, tests and supports military jet engines and space propulsion systems. Still photography is available to support this release. Photos are also available on the Internet under "NASA Dryden Research Aircraft PHOTO ARCHIVE, Dryden News and Feature Photos, URL: /centers/dfrc/Gallery/Photo/index.html


Note to Editors: Photos in support of this release:

EC 96 43485-3 EC 96 43485-5 EC 96 43485-6 EC 96 43485-13


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