Office of Aerospace Medicine Technical Reports

FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute


Report No: DOT/FAA/AM-71/17

Title and Subtitle: Combined effects of altitude and high temperature on complex performance

Report Date: April 1971

Authors: Chiles WD, Iampietro PF, Higgins EA, Vaughan JA, West G, Funkhouser GE

Abstract: Nine well-trained subjects were tested on a complex performance device designed to assess functions of relevance to aircrew activities. The tests, which involved tracking, monitoring, and mental arithmetic, were performed during exposure to altitude (14,000 feet) and heat (60 C.) both singly and in combination.

Several physiological measures were taken. Exposure durations were 30 minutes for each condition with both pre- and post-testing. The only clear-cut effects of the conditions were significant differences across the environmental conditions on a perceptual-motor tracking task related to manual aircraft control. Altitude was clearly a more powerful variable than temperature in this study. This was evidenced by the fact that performance under the temperature-plus-altitude and the altitude-only conditions were approximately the same; performance under the temperature-only condition was significantly better than performance for either of the other two conditions.

There was some evidence that the two environments in combination produced a persistent effect on performance that did not dissipate with return to normal conditions. Measured physiological functions of the subjects were within the tolerable range.

Key Words: Heat, High Temperatures, Physiological Responses, Psychological Performance, Aircrew, Pilots, Suersonic Aircraft, Altitude, Hypoxia

No. of Pages: 10

Last updated: Friday, June 1, 2012