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Photos

Snapshots of what’s happening in the Defense Department.

The face of a man, wearing protective glasses, is seen through windows in a large metal tube. Inside the tube is a pointed metallic object.

Ludwieg Tub

Air Force Cadet 2nd Class Eric Hembling uses a Ludwieg Tube to measure the pressures, temperatures and flow field of various basic geometric and hypersonic research vehicles at Mach 6 in the U.S. Air Force Academy's Department of Aeronautics, Jan. 31, 2019.

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