NACA microphone actuator at the Lewis Flight Propulsion Laboratory (now Glenn Research Center), c. 1955. Full caption: "MICROPHONE ACTUATOR ON HANGAR APRON"
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1956 NACA metallurgical services worker - photo
1956 NACA wind tunnel wall jacks - photo
1952 NACA heat transfer test section and rig - photo
1951 NACA 20-inch compressor in lathe - photo
1954 NASA chemist - photo
Constructing NACA's wind tunnel propellers - GIF