By use of a battery of urinary techniques, the physiologic cost (stress) of prolonged C-141 flying operations was shown to be mild-to moderate in degree. Staged missions lasting 5 or 7 days tended to be less stressful than double-crew nearly-continuous 50-hour missions. In the latter type of mission, two extremely different work/rest schedules, namely, 4/4 and 16/16 hours, induced similar degrees of physiologic stress. Anticipatory stress which was detected prior to double-crew flights tended to be higher than the flight stress that followed. Crew position was a contributory factor, slightly modifying flight and postflight trends. Pre-existing circadian periodicity persisted, although flight had modifying influence. Time of day that represented night at home were the times of highest sensitivity to flight. Recovery from prolonged nearly-continuous flying operations appears to require 4-5 days, and it appears to be a multiphasic process, with endocrine-metabolic depression appearing first, after which there was oscillation and final settling at the control level. In one double-crew mission, when extraordinary fatigue was noted, there had been a 12-hour pattern of change in the physiologic stress index that suggested an 'overload' reaction. (Author)
Physiologic Stress during 50-Hour Double-Crew Missions in C-141 Aircraft
1971
9 pages
Report
No indication
English