Centrifuge training program with "push-pull" elements

Pilots of fighter aircraft are often exposed to maneuvers that produce negative acceleration (-Gz) immediately followed by positive acceleration (+Gz). This sequence has been found to reduce tolerance to +Gz, a phenomenon known as the "push-pull" effect. We devised a centrifuge training program to demonstrate this phenomenon to pilots.

The centrifuge of the Military Institute of Aviation Medicine in Warsaw, Poland, was modified in 1996 to allow active positioning of the gondola during rotation. Head-down position of -6 degrees to -40 degrees were used to produce relative -Gz (r-Gz) in a range down to 0.2. As a side effect, this produces Gy acceleration between -1.3 Gy and -1.6 Gy. Pilots completed normal centrifuge training, including a relaxed, gradual-onset run and three rapid-onset runs. They were then exposed to a profile that included a series of push-pull exposures where r-Gz was followed by +Gz with stepwise increases in the latter from +2.5 to +5 Gz. The final profile was a simulated aerial combat maneuver with push-pull elements.

The trainees expressed surprise at the push-pull effect, which forced them to begin an anti-G straining maneuver at lower levels than normal. They complained about the presence of the Gy, which rarely occurs in aircraft.

This type of profile appears useful for training pilots about the push-pull phenomenon. After collection of additional data, the profiles may be refined.