MOL: Crew performance on demanding work/rest schedules compounded by sleep deprivation

Abstract

This experiment was conducted as a specific response to work/rest questione posed by the medical group supporting the Manned Orbiting Laboratory program.This report has been reviewed and is approved. GEORGE E SCHAFER Colonel, USAF, MC Commander i I :i ABSTRACTfThirteen subjects Look part in it series of 12-day runs in an experiment on the effects of demanding work/rest schedules (4/2, 4/4, or 16/8 hours). On days 8, 9, and 10, subjects were deprived of sleep one worked continuously.No significant work/rest effects were seen until hubjects were sleep-deprived. In general, subje-ts on the 161'" schedule tolerated sleep deprivation better and recovered faster, as evidenced by psycihomotor test scores and Pleel, report3. HMt: CREW P NHANCE ON D WN6 WOR,/R7 KHEDUW CONPOUB ) BY SLEEP DEPRIVATIO I. INTRODUCTIONThe study showed that: (1) learning curves were obtained during the initia! , ' U s, but the Manned space flight to date provides a rate of learning was less for subjects on the somewhat mixed picture on work/rest sched-4/2 iedule than for subjects on the 4/4 ules. Clearly, those in-orbit tasks which relate schedule; (2) both groups suffered performto ground tracks and orbit times require relaance decrement during sleep deprivation, but tively brief crew performance periods when the decrement was greater on the 4/2 schedule compared to a conventional 8-hour work day.than on the 4/4 schedule; (3) diurnal variaIn the early planning for the Manned Orbiting tions persisted throughout sleep deprivation; Laboratory (MOL), specific attention was givand (4) subjective alertness was degraded duren to crew schedules which would provide ing sleep deprivation, partially recovered after relatively short periods of work and rest althe first postdeprivation sleep period, and fully ternating around the clock. Questions were recovered by the end of the first postdeprivaraised concerning the effect of such schedules tion day, with performance measures confirmon crew efficiency.ing these changes grossly.

Extending human effectiveness during sustained operations through sleep management.

“…Sustained Operations (SUSOPs) of "sustained performance" was defined by Alluisi as "the more or less continuous per- The single most important limitation in SJSOP appears to be the human factoi This is largely due to the detrimental effects of sleep deprivation and has been well documented in both laboratory and field studies (6,9,23,(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45).…”

Human Factors in Long-Duration Spaceflight

“…Obviously, such a fixed pattern of work responsibility could lead to the formation of two or more subgroups whose goals and interests might eventually conflict with over-all mission goals. Adams and Chiles (1960), Alluisi et al (1963), Hartman and Cantrell (1967), and Chiles et al (1968) all reported that rotating shifts which led to frequent disruption of circadian cycles were associated with irritability and some impairment of performance. Nevertheless, the data of Alluisi et al (1963) suggested that with proper control of selection and motivational factors, crews could "work effectively for periods of at least two weeks and probably longer using a schedule of 4 h on duty and 2 h off."…”