Findings from a simulated disabled submarine survival trial.

Eleven volunteer submariners were exposed to simulated disabled submarine conditions for a maximum of 7 days to determine if the limited clothing and rations provided in escape compartments would compromise survival prospects. Daily rations were 0.568 liters of water (none on Day 1) and 100 g of barley sugar. The subjects wore working rig and the liner from the Mark 10 submarine escape and immersion equipment throughout, and slept in the outer dry suit. Air temperature fell from 22 degrees to 4.4 degrees C over 2 days and then remained at 4.4 degrees C. Although the subjects felt cold they were able to maintain their deep body temperature. The greatest threat to survival in this situation would be dehydration, one subject was withdrawn on Day 4 as his urine production over the previous 24 h was 130 ml and if not withdrawn and rehydrated this may have led to renal failure. Other medical problems suffered by the subjects during the 7 days included diarrhea, vomiting, hypoglycemia, headaches, and back pains, and, following the trial, non-freezing cold injuries to their feet. It is concluded that the rations are not adequate and could compromise the submariners ability to survive for 7 days in these conditions and during a subsequent escape procedure.