very well nauseate the occupants and be 

 quite detrimental to the mission. Dr. R. C. 

 Bornmann, Captain, USN, (personal commu- 

 nication) states that for a short duration 

 exposure and with human occupants in good 

 health, there is no danger to their health 

 from the gasses evolved, other than their 

 noxious effects. 



Temperature-Humidity Control 



Aspects of the cabin environment that 

 have a direct effect on both occupants and 

 electronic equipment are temperature and 

 humidity. Only a handful of submersibles 

 provide control of these variables and the 

 results, as we saw from the JOHNSON SEA 

 LINK, can be fatal in the extreme. For the 

 most part, however, high and low tempera- 

 tures and high humidity are inconveniences 

 that are tolerated until the dive is finished. 

 But in some instances, the lack of control can 

 seriously alter the mission. For example, it 

 was planned to conduct periodic 24-hour bot- 

 tom excursions during BEN FRANKLIN's 30- 

 day Gulf Stream Drift, but none of these 

 excursions lasted more than 9 hours because 

 the temperature in the cabin dropped into 

 the low 50's (°F). While this temperature was 

 tolerable, the correspondingly high humidity 

 (82%) produced a bone-chilling cold that left 

 little more on the occupant's mind than to 

 get warm (Fig. 9.8). Concentration on any- 

 thing else was all but impossible. The situa- 

 tion was corrected by ascending into shal- 

 lower, warmer waters. 



On the opposite end are the effects of high 

 temperature and high humidity. During 

 tropical operations with DS-4000 , Merrifield 

 (12) reports cabin temperatures of 100°F and 

 100 percent humidity when operating at less 

 than 600 feet — v.'ith the result that the occu- 

 pants' effectiveness was seriously impaired. 



The enervating effects of high tempera- 

 ture and humidity can begin long before the 

 vehicle submerges. In the tropics and sub- 

 tropics between-dive maintenance aboard 

 ship requires the support personnel to work 

 in the vehicle where conditions can become 

 almost unbearable unless some form of air- 

 conditioning is provided. Many support ships 

 are equipped to blow cool air into the cabin 

 to maintain a habitable environment. 



Large vehicles of the ALU MINAUT variety 

 produced some unusually trying cabin condi- 



"^npnrfif* 



Fig 98 Just prior to an aborted bottom excursion dunng BEN FRANKLIN'S Gulf 

 Stream Drrtt trie auttior. wrapped in a blanket and weanng a foam-rubber pad to 

 cushion contact between his head and the steel-rimmed viewport, stares balef ully at a 

 fellow passenger An IjOH panel and several 5-lb bags of silica gel can be seen in 

 the bacltground. (Grumman Aerospace Corp ) 



tions when operating in the tropics. ALUMI- 

 NAUT''s general operating procedure was to 

 cast off the towline and transfer the observ- 

 ers by rubber raft from support ship to sub- 

 mersible. The observers were instructed to 

 wear long pants and sweaters, because the 

 cabin temperature would get quite chilly 

 after a few hours in the 40° to 50°F bottom 

 waters. When the passengers embarked, the 

 interior of the vehicle had almost unbearably 

 high temperature and humidity. Perspira- 

 tion before the vehicle dived produced 

 soaked clothing. When the vehicle reached 

 operating depth and temperatures dropped, 

 the wet clothing only served to aggravate 

 the situation. The final solution was to em- 

 bark in shorts, towel off at depth when the 

 vehicle cooled and then change to heavier 

 clothing which was kept dry within a plastic 

 refuse bag. 



428 



