Predictions of Human Tolerance to Heat Stress While Wearing Advanced IntegratedSuit Concepts During Simulated Realistic Combat Scenarios

摘要

Aircrew garment ensembles with increased body surface coverage designed toenhance G-tolerance were modelled to determine their effects on thermal loading during simulated realistic combat Scenarios. Heat stress is known to decrease G-tolerance. Physiologic responses were estimated using the Texas Human Thermal Model (THTM). Predictions included rectal and mean skin temperatures, heart rate, sweat rate and accumulated sweat (SWT) during an 'alert 5' with aerial combat maneuvers and normal operations with/without ACM. Five ensembles were modelled: USN winter ensemble with (WE) or without an EAGLE with a USN COMBAT EDGE (CE) counter pressure jerkin and a USN summer ensemble with CE and either an EAGLE (E), ATAGS (A) or ATAGS with additional arm coverage (AA). Simulations were run under cool, warm and hot conditions. Since no fluid intake was allowed during these simulations, SWT provided an estimate of dehydration. The hot alert 5 scenario was the most thermally stress due to the waiting period on the flight line without cooling. Reduced G-tolerance was predicted prior to simulated engagements with degraded CNS function for WE, A and AA. Similar CNS function deficits were not predicted for other scenarios. Few statistical differences were found during warm conditions for any scenario. Overall, E was predicted to produce a relatively lower thermal load than the other summer ensembles. External cooling should be provided during hot alert 5 conditions to avoid negating the enhanced G-tolerance benefits obtained from wearing increased coverage anti-G suits.