Centrifuge at the Aviation Medical Acceleration Laboratory.
The Johnsville Centrifuge was a facility at the Aviation Medical Acceleration Laboratory of the Navy Air
Development Center, Johnsville, Pennsylvania, used throughout the early
American space program; it was the most powerful centrifuge then in existence. With a 17-meter radius, it had a rate change of 10g per second
and could reach 40g per second. The 3- by 1.8-meter-diameter gimbal-mounted
gondola was fully air-conditioned.
Prior to the arrival of the Mercury astronauts in August 1959, the Johnsville Centrifuge was used for testing by X-15 pilots – including Neil Armstrong prior to his selection by NASA. To this day, the Johnsville Centrifuge holds the distinction of being the largest human centrifuge ever built. In addition to the Centrifuge, the developments at the Johnsville Naval Air Development Center (NADC) included pioneering work on GPS, transition lenses, ejection seats, and "black boxes".