Accession Number : ADA291600

Title :   Predictions of Human Tolerance to Heat Stress While Wearing Advanced Integrated Suit Concepts During Simulated Realistic Combat Scenarios.

Descriptive Note : Final rept. Jun-Sep 93,

Corporate Author : NAVAL AIR WARFARE CENTER AIRCRAFT DIV WARMINSTER PA AIR VEHICLE AND CREW SYST EMS TECHNOLOGY DEPT

Personal Author(s) : Shender, Barry S.

PDF Url : ADA291600

Report Date : 15 OCT 1993

Pagination or Media Count : 84

Abstract : Aircrew garment ensembles with increased body surface coverage designed to enhance 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.

Descriptors :   *FLIGHT MANEUVERS, *TOLERANCES(PHYSIOLOGY), *FLIGHT CLOTHING, *HEAT STRESS(PHYSIOLOGY), STRESSES, THERMAL PROPERTIES, SCENARIOS, FUNCTIONS, MODELS, FLIGHT CREWS, TEMPERATURE, HUMANS, EDGES, RATES, COOLING, SURFACES, WINTER, AERIAL WARFARE, DEFICIENCIES, PHYSIOLOGICAL EFFECTS, G SUITS, EXTERNAL, MEAN, RESPONSE(BIOLOGY), ACCUMULATION, HEART RATE, TEXAS, SUMMER, CENTRAL NERVOUS SYSTEM, DEHYDRATION, SKIN(GENERAL), RECTUM, PERSPIRATION.

Subject Categories : Human Factors Engineering & Man Machine System
      Protective Equipment
      Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE