8/17/2011 - Staff Sgt. Frederick Keese calibrates a boresite fixture for an inertial unit and battery system Aug. 16 at Aviano Air Base, Italy. This fixture is used to line up navigation and weapons systems on F-16 Fighting Falcons. Keese is assigned to the 31st Maintenance Squadron precision measurement equipment laboratory and is a physical dimensional section supervisor. (U.S. Air Force photo/Airman LaVel Sterling)

8/17/2011 - Staff Sgt. Juan Mercado Guzman calibrates a gas port erosion tool Aug. 16 at Aviano Air Base, Italy. Mercado Guzman works in the 31st Maintenance Squadron precision measurement laboratory as a technical measurement diagnostics equipment technician. The PMEL office members calibrate more than 6,000 pressure measuring devices for seven different bases throughout Europe. (U.S. Air Force photo/Airman LaVel Sterling)

8/17/2011 - Jeffery Logsdon uses a primary pressure sender to calibrate a pressure controller Aug. 16 at Aviano Air Base, Italy. The primary pressure sender is the standard calibration for all of Europe, and any piece of equipment that measures pressure can be traced back to this machine. Logsdon is assigned to the 31st Maintenance Squadron precision measurement equipment laboratory as a technical measurement diagnostics equipment technician. (U.S. Air Force photo/Airman LaVel Sterling)

8/17/2011 - Senior Airman David Blake adjusts the internal resistance of a 501 test set Aug. 16 at Aviano Air Base, Italy. The 501 test set is designed to give pilots operational control over weapons systems and troubleshoot stores management systems. Blake is assigned to the 31st Maintenance squadron precision measurement equipment laboratory as a technical measurement diagnostics equipment technician. (U.S. Air Force photo/Airman LaVel Sterling)

8/17/2011 - Staff Sgt. Caleb Jackson and Airman 1st Class Andrew Smith troubleshoot an oscilloscope Aug. 16 at Aviano Air Base, Italy. The oscilloscope is used to give a visual analysis of voltage and time. Jackson and Smith are assigned to the 31st Maintenance Squadron precision measurement equipment laboratory as technical measurement diagnostics equipment technicians. (U.S. Air Force photo/Airman LaVel Sterling)