Rob Hale, engineering technician, left, Parth Kathrotiya, system engineer, center, and Zack Russo, engineering technician, pose with the Mach 18 nozzle at AEDC Hypervelocity Wind Tunnel 9 in White Oak, Maryland. The team at Tunnel 9 recently completed an initial shakeout of the Mach 18 system, and the calibration to bring Mach 18 to full operating capability is set to occur later this year. (U.S. Air Force photo by A.J. Spicer) (This image has been altered by obscuring badges for security purposes)