Vestibular function in military pilots before and after 10 s at +9 Gz on a centrifuge.
ABSTRACT Effects of high Gz acceleration can threaten flight safety through loss of consciousness or a lesser-known phenomenon, G-induced vestibular dysfunction (GIVD). There are reports of GIVD following high-G flight or centrifuge exposure. The aim of this study was to explore this problem under controlled conditions using a human centrifuge.
There were 11 pilots who were exposed to +9 Gz for 10 s. Measurements were made before and after G exposure to assess vestibular function, including spontaneous nystagmus, positioning nystagmus, optokinetic nystagmus, vestibular ocular reflex, vestibular-vision interaction, subjective vision vertical perception, and vestibular-evoked myogenic potentials.
No significant change was found for vestibular function after the Gz exposure.
It appears +9 Gz for 10 s does not produce GIVD. However, the possible effects of prolonged high G maneuvers in modern aircraft combined with head movements may warrant further study.
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