The Effects of a 48-Hour Period of Sustained Field Activity on Tank Crew Performance

Abstract

This report describes the effects of 48 hours of sustained operations on the performance of tank crews in communication, driving, surveillance, gunnery, and maintenance tasks. It is a continuation of research to determine the endurance of troops using combat equipment with 48-hour capability. Proficienty tests were constructed for each type of tank-crew activity and made part of a 12-hour field exercise. Two groups of crews were used; one group ne 3tiated a problem course four consecutive times for a total of 48 hours of continuous operation, and a control group followed the-lame procedure but had 24-hour rest periods between each 12 hours r' operation. Only moving sul:veillance and some driving activi"showed significant performance deterioration over a 48-hour I of work without sleep. Major conclusions were: (1) No serious performance decrements result from operating present tank equipment continuously for 48 hours without sleep; (2) Performance at night is not significantly affected by the subject's diurnal rhythm; (3) No major changes in present unit organization and tactical doctrine are necessary to accomplish continuous tank operations for periods up to 48 hours.

Effects of Cargo Loading and Unloading on Truck Driver Alertness

“…A survey of the literature (1) found little informative research on the link between physical efforts, such as loading and unloading, and performance. The presumption is that physical work of sufficient intensity affects other performance variables as a component of fatigue- Mackie & Miller (6)-but this hypothesis has not been tested adequately (2)(3)(4)(5)(6).…”

Sustained performance and some effects on the design and operation of complex systems

“…Examples of slightly longer duration were provided by Murray & Lubin (1958), Wilkinson (1962Wilkinson ( , 1964 and Williams & Lubin (1967). The few field trials there were (Banks et al 1970;Haggard 1970;Dudley et al 1974) had been of relat 5 days) and only two had aimed at military realism (Drucker 1969;Ainsworth & Bishop 1971). Historical evidence from battle and expert opinion gave widely differing answers as to how much sleep was necessary to remain militarily effective for nine days, and so we embarked on a series of five trials, two in the field, two in the laboratory and one combined, to provide best estimates of likely performance under agreed military scenarios.…”