HUMAN TOLERANCE FOR SHORT EXPOSURES TO HEAT
Abstract
The development of very high speed fighter air craft poses the problem of excessive cockpit temperatures, particularly in fast sweeps at low altitude. The heat arises from three sources, namely: solar radiation transmitted through the plexiglas bubble canopy; friction of the air passing over the surface of the fuselage; and the heat of ram pressure. For example the last named phenomenon may cause a temperature rise above OAT of 29 F at a speed of 400 m.p.h.; this value increases to 45 F at 500 m.p.h. and to 64 F at 600 m. p.h. If to this is added another 10 to 15 F effective temperature due to solar radiation, cabin temperatures in excess of 150 F may be expected even when ambient temperatures are not higher than 90 to 100 F. Since the duration of exposure to these high temperatures is expected to be short, 15 to 30 minutes at a maximum, as limited by the tactical use of the airplane and the fuel supply, steady states of human heat balance are not required. The biophysical problem is to determine points on a duration-intensity curve which are tolerable for Air Force personnel. In selecting these points, it must be assumed that pilots are not heat acclimatized and that they represent a range of constitutional and fitness types.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 28, 1945
- Accession Number
- AD0410729
Entities
Organizations
- Air Force Research Laboratory