title: A centrifuge simulated push-pull manoeuvre with subsequent reduced +Gz tolerance.
abstract: The push-pull effect (PPE) has been recognized as a deleterious contributor to fatal flight accidents. The purpose of the study was to establish a push-pull manoeuvre (PPM) simulation with a tri-axes centrifuge, studying the effect of this PPM on the +Gz tolerance, and to make this simulation suitable for pilot centrifuge training. The PPM was realized through pre-programmed acceleration profiles consisting of -1 Gz for 5 s followed by a +Gz plateau for 10 s. Relaxed +Gz tolerance recordings were obtained from 20 healthy male fighter aircraft pilots and 6 healthy male volunteers through exposure to pre-programmed profiles with and without previous -1 Gz exposure. A statistically significant decrease in +Gz tolerance was seen in all subjects after -1 Gz for 5 s exposure, 0.87 ± 0.13 G in the volunteer group and 0.95 ± 0.25 G in the pilot group. The ear opacity pulse as a +Gz tolerance endpoint criterion was sometimes found to be unreliable during the PPM experiments. The simulated PPM in this study elicited a PPE, which was obvious from the significant reduction in +Gz tolerance. The PPM profile appears useful to be included in centrifuge training.
authors.affiliation: Department of Aerospace Biodynamics, Faculty of Aerospace Medicine, Fourth Military Medical University, Xi'an, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xu
authors.forename: Bao-Hui
authors.initials: BH
authors.lastname: Li
authors.forename: Li-Hui
authors.initials: LH
authors.lastname: Zhang
authors.forename: Zhao
authors.initials: Z
authors.lastname: Jin
authors.forename: Xiao-Yang
authors.initials: XY
authors.lastname: Wei
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.forename: San-Yuan
authors.initials: SY
authors.lastname: Wu
authors.forename: Hai-Xia
authors.initials: HX
authors.lastname: Wang
authors.forename: Quan
authors.initials: Q
authors.lastname: Wang
authors.forename: Gui-Ding
authors.initials: GD
authors.lastname: Yan
authors.forename: Lue
authors.initials: L
authors.lastname: Deng
authors.forename: Xi-Chen
authors.initials: XC
authors.lastname: Geng
mesh_terms: D000054:Acceleration; D000222:Adaptation, Physiological / Q000502:physiology*; D000401:Aircraft; D002498:Centrifugation; D017753:Ecosystem; D006225:Hand / Q000502:physiology*; D006801:Humans; D018471:Hypergravity; D008297:Male; D009068:Movement / Q000502:physiology*; D013647:Task Performance and Analysis; D055815:Young Adult
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