This is the first C-17 (YC-17A), USAF s/n 87-0025, c/n 50002, according to Joe Baugher's information site. He further adds, "Aircraft retired to USAF Museum, arriving there on April 25, 2012".

The USAF National Museum's site notes, "This C-17 Globemaster III (S/N 87-0025) was essentially hand-built for the sole purpose of developmental test and evaluation, with an estimated life span of approximately five years. The aircraft was periodically rebuilt and refurbished over the years and its lifespan grew from five to 21 years."

Additionally, "T-1 made its first flight on Sept. 15, 1991, when it was delivered to the USAF at Edwards AFB, Calif., for testing. After completing the extensive C-17 flight test program, T-1 supported many other flight and propulsion test programs for the USAF, NASA and others."