Tech

July 16, 2014

New life for an old bird: NASA’s F-15B test bed gets new engines

NASA’s F-15B flight research test bed carries shuttle thermal insulation panels on its underbelly during a research flight in 2005.

NASA Armstrong’s F-15B aeronautics research test bed, a workhorse at the center since 1993, has received an engine upgrade that will keep the airplane flying well into the foreseeable future.

Prior to this work Armstrong officials were considering retiring the F-15B, which carries NASA tail number 836, and replacing it with a newer F-15D model. An advanced data acquisition system gives the F-15B a capability that makes it one of the most versatile research aircraft NASA flies, but transferring the extensive research instrumentation to the newer aircraft would be very costly and time-consuming, and result in delays to projects needing the F-15s’ capabilities.

NASA’s F-15B is the oldest F-15 still flying and maintenance support for the airplane’s engines was becoming increasingly difficult. However, NASA Armstrong’s recent acquisition of six new engines with digital controls will greatly extend the F-15B’s service life.

The U.S. Air Force has retired all early model F-15A and F-15B aircraft, all of which, including NASA 836, were powered by Pratt & Whitney F100-PW-100 engines. Following phase-out of the F-15A/B, those engines were no longer supported by the Air Force supply chain. In the hope of keeping NASA 836 flying and eventually replacing it with a newer model, Armstrong acquired three F-15D aircraft from Tyndall Air Force Base, Florida that were surplus to Air Force needs. One of these was put on flight status while the other two were primarily used to provide spare engines.

Around the same time, according to F-15 crew chief Walter Kondracki, two F-100-PW-229 engines were removed from NASA’s highly modified NF-15B No. 837, which had been retired from service. Both powerplants required full teardown and rebuild following long years of service. In the meantime maintenance crews struggled to keep NASA 836 flying for the next few years.

“By the summer of 2012 we had removed and replaced six engines in 836,“ Kondracki said. “It decimated our spare engine supply and replacement parts were $300K, plus labor, with little or no funding available for repairs.“

NASA’s Armstrong Flight Research Center has flown this modified F-15B Eagle as a research test bed and mission support aircraft since the early 1990s.

Then, through a fortuitous set of circumstances, Armstrong acquired some F100-PW-220 engines, which are equipped with more advanced technology than in the -100 including digital electronic controls, as well as improved durability and reliability. Tom Grindle, Armstrong’s chief of maintenance, learned that the Air Force needed a set of -229 engines for an F-15E and arranged to swap the two rebuilt powerplants from NASA 837 for six -220 engines.

Adapting the F-15B to accept the new engines required modifying the airplane’s electrical wiring system. Ron Rohe, lead F-15B avionics technician, learned that engine wiring harnesses for the -220 were no longer available from the Air Force so he developed a plan to modify the airplane’s electrical system. After comparing the original -100 wiring configuration against that of the -220 he developed a hybrid solution using the existing wiring and incorporating changes that allowed the -220 engines to function properly.

The F-15B project team then contracted Boeing to review the proposed wiring modifications and, with only minor changes, the plan was approved in March 2014.  Rohe and L-3 avionics technician Chris Brookes completed the modifications in less than three weeks.

Kondracki’s F-15 maintenance crew then installed the new engines and NASA research pilot Nils Larson conducted a ground run to ensure the engines were fully functional from idle power to full afterburner.  Research pilot Jim Less and flight-test engineer Tom Jones performed a functional check flight on June 4 and found that the engines and their associated electronics performed flawlessly.

Project officials expect this engine upgrade to extend the F-15B’s service life for several more years and allow for continued supersonic research. High Speed Project support manager Brett Pauer said the new engines will increase reliability, and decrease maintenance downtime between flights.
 

NASA’s workhorse F-15B Aeronautics Research Test Bed carries an experiment to measure local Mach number during a 2009 research project. The aircraft has been used as the platform for a wide range of experiments and research projects requiring an aircraft with supersonic capability.




All of this week's top headlines to your email every Friday.


 
 

 

Headlines December 19, 2014

News: SpaceX’s attempt to land rocket on floating barge postponed - It’s set to be one of the most groundbreaking moments in humanity’s six decades of space exploration. Obama signs $1.1 trillion spending bill into law - President Obama signed the $1.1 trillion federal spending measure into law Dec. 16, officially ending any threat of a government...
 
 

News Briefs December 19, 2014

Trial set for ex-Navy engineer in military secrets case A former Navy civilian engineer is scheduled to stand trial next summer on charges of trying to steal aircraft carrier schematics. Media outlets report that 35-year-old Mostafa Awwad of Yorktown, Va., pleaded not guilty Dec. 17 to two counts of attempted exportation of defense articles and...
 
 
Army photograph by C. Todd Lopez

Army to launch cruise missile-detecting aerostat at Aberdeen Proving Ground

Army photograph by C. Todd Lopez The Army plans to launch an aerostat, part of the “Joint Land Attack Cruise Missile Defense Elevated Netted Sensor,” in late December 2014. The JLENS aerostat will be tethered to the...
 

 
Air Force photograph by SrA. Jordan Castelan

AF delivers Iraqi F-16s for training in US

Air Force photograph by SrA. Jordan Castelan Iraqi air force captain Hama conducts preflight inspections while inside a new to service Iraqi F-16 Fighting Falcon Dec. 17, 2014, located at the nearby Tucson International Airport...
 
 
Air Force photograph by SSgt. Derek VanHorn

Short-notice: A new way to exercise

Air Force photograph by SSgt. Derek VanHorn Airmen from Kadena Air Base, Japan, prepare for an aeromedical evacuation exercise on a KC-135 Stratotanker Dec. 5, 2014, at Misawa Air Base, Japan. The operation was executed in supp...
 
 
Lockheed Martin photograph by Andy Wolfe

Japan, Australia to provide F-35 maintenance sites in Pacific region

Lockheed Martin photograph by Andy Wolfe An F-35C Lightning II joint strike fighter carrier variant prepares to launch from the aircraft carrier USS Nimitz in the Pacific Ocean, Nov. 6, 2014. Japan and Australia will be sharing...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>