The Effect of Aircrew Age on +Gz Tolerance as Measured in a Human-Use Centrifuge. (Abstracts)

Abstract

Abstract : A data repository was established in 1988 to compile information on 1,120 aircrew (74% pilots) who underwent acceleration (+Gz) tolerance training at NAWOAD Patuxent River human-use centrifuge. 51% of the aircrew flew in high performance aircraft (F4, F14, F15, F16, and Fl 8). The trainees were U.S. Navy/Marine Corps (70%) and Air National Guard (30%) aircrew. Balanced data from 817 healthy male trainees were examined. Mean age (+S.D.) was 31.4 i 6.8 years (20 to 5g). Relaxed tolerance was 4.91 i 0.93 +Gz and was shown to be independent of age (R2 - 0.005). Straining tolerance was 7.17 + 1.27 +Gz. Age did not have an effect on straining +Gz tolerance (R2 = 0.017). The protection afforded by the AGSM was 2.72 j 0.84 +Gz and was not affected by trainee age (R2 = 0.007). Age did not demonstrate to have an effect on G-LOC incidence. Exposures where cardiovascular data was analyzed (n=1 9) ranges from 5 to 9 +Gz (5.5 i 1.3). The change described by MHR-RHR was 57 i 21 bpm. The change described by MHR-RCVHR was 62 * 27 bpm. Multiple regress demonstrated that age and the +Gz level at which the MHR occurred (GMHR) explained 55% of the variability in MHR-RCVHR (R2 age = 0.18, pT% = 0.01; R2 GMHR = 0.37, pT% = 0.002). The model was described by MHR-RCVHR = 19.03 - 1.40*age + 13.08+GMHR (F= 9.87, p = 0.001). No statistically significant relationship was found based on change in MHR-RHR. The relative long duration GOR exposures are typically used to determine cardiovascular +Gz tolerance in human-use centrifuge studies. Based on the variables examined in this retrospective stud there does not seem to be a Significant effect on a e on +Gz tolerance.