Diver Performance in Controlling a Wet Submersible During Four-Hour Exposures to Cold Water

Six 4-hr., open-sea test trials were conducted with a wet submersible. The purpose of these trials was to assess the effects of long exposure to cold (16.5° C) water on man's ability to perform basic submersible control tasks. The subjects were experienced submersible pilots who had a minimum of 20 hours training prior to the experimental trials. Skin and rectal temperatures were continuously recorded from both the pilot and rider of the submersible. A continuous record of vehicle depth and water temperature was also obtained. The pilot's task was to maintain a prescribed depth while performing a sequence of course changes for a 4-hr. period of submergence. Depth error variance was correlated with pilot core and skin temperature changes over time, and although pilot core temperature fell as much as 1.83° C, no degradation in depth control performance was apparent.