NASA - National Aeronautics and Space Administration

NASA Dryden’s F-15B research testbed aircraft flew the CCIE experimental jet engine inlet to speeds up to Mach 1.74, or about 1.7 times the speed of sound. (NASA / Jim Ross) The F-15B Research Testbed continues to be an innovative and cost-effective tool for flight test of advanced propulsion concepts. Also known as #836, this is a modified twin-engine jet aircraft that provides NASA, industry, and universities with long-term capability for the efficient flight test of aerodynamic, instrumentation, propulsion, and other flight research experiments. This aircraft is a unique airborne resource, and is considered by researchers to be a virtual "flying wind tunnel” and reliable supersonic testbed. In addition to flying research missions, Dryden's F-15B also is used for crew training, pilot proficiency, and safety chase support for other research aircraft.

The data acquisition system in the aircraft makes the F-15B one of the most versatile testbed aircraft NASA flies. An on-board video system monitored from the rear seat of the cockpit provides a high-speed airborne video and photo capability that can be downlinked to researchers on the ground. The data system includes a research airdata system for the aircraft, as well as a Global Positioning System (GPS) navigation package; a radome with a nose boom that contains an airdata probe; a digital data recorder; and telemetry antennas.

Recent Activity:
Eagle Aero Probes

In 2011, #836 was used to flight test two new supersonic shockwave probes to determine their viability as research tools. Sonic boom researchers hope the Eagle Aero probes (Eagle Aeronautics, Hampton, VA) will aid their understanding of supersonic shockwaves. The ultimate goal of NASA's sonic boom research is to find ways to control the shockwaves and lessen the noise, so that it may be possible for supersonic flight to become more routine. For more information: http://www.nasa.gov/topics/aeronautics/features/shockwave_probes.html

Channeled Center-body Inlet Experiment (CCIE)

Researchers also used #836 in 2011 to complete flight tests of a unique experimental jet engine inlet design in the Channeled Center-body Inlet Experiment (TechLand Research, Inc., North Olmsted, OH). The CCIE project's primary research objective was to define the airflow through the experimental jet engine inlet, then compare it to the airflow through a standard inlet. Potential future applications for the simplified inlet design include its use on a new generation of supersonic cruise aircraft, reducing the complexity and weight of this important component of supersonic propulsion systems. For more information: http://www.nasa.gov/centers/dryden/Features/ccie.html

The Propulsion Flight Test Fixture (PFTF) was flown in 2009 to quantify the flow field surrounding a research inlet. This project brings the PFTF one step closer to full operational capability, which will allow the F-15B to demonstrate and study advanced propulsion concepts in flight. See http://www.nasa.gov/centers/dryden/news/FactSheets/FS-055-DFRC.html

In 2008, #836 was flown by several research projects to help understand and overcome the challenges associated with providing civilian overland supersonic transport as well as advanced propulsion system design.

Lift and Nozzle Change Effects on Tail Shock (LaNCETS) quantified how changes in lift distribution and nozzle area ratio affect the supersonic shock structure on the aft end of NASA’s highly modified F-15 (#837) research aircraft. See http://www.nasa.gov/centers/dryden/news/NewsReleases/2009/09-04.html

In 2006, Gulfstream Aerospace and Dryden teamed in a project called Quiet Spike™ to investigate the suppression of sonic booms. The project centered around a retractable, 24-foot-long lance-like spike mounted on the nose of NASA Dryden's F-15B (#836) research testbed aircraft. The spike, made primarily of composite materials, created three small shock waves that traveled parallel to each other all the way to the ground, producing less noise than typical shock waves that build up at the front of supersonic jets. This highly successful project put spike-induced sonic boom suppression theory to the test in the actual flight environment afforded by NASA's supersonic F-15B.

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Points of Contact

Jim Smolka
Director for Flight Operations (Acting)
661.276.3210
jim.smolka-1@nasa.gov

Mariaelena A. Nichols
Flight Operations Business Analyst
661.276.3099
Mariaelena.A.Nichols@nasa.gov

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