The Effect of High Acceleration Forces Upon Certain Physiological Factors of Human Subjects Placed in a Modified Supine Position: Sdc Project 9-U-37a: Position 3

摘要

Six male subjects were exposed to acceleration forces up to 12 G resultant for 5-8 seconds on the human centrifuge. During these exposures they were in a modified supinated position in which the bent knees placed the feet at a level somewhat below that of the rest of the body. During rotation of the centrifuge the seat pivoted so that the resultant G force was supplied to the subject in a direction from chest to back. Consciousness, vision, and voluntary finger movements at the highest G obtainable on this centrifuge were not impaired under these conditions. Human tolerance to G force under these conditions seemed to be restricted by respiration and pain. Ear opacity and ear pulse were relatively poor indicators of the cardiovascular changes taking place under these conditions. The cardiovascular system, according to the heart rate and electrocardiogram, did not show severe enough changes to consider it as one of the important factors of human tolerance to G force under these conditions. The pracitcality of this position for aircraft personnel were discussed. (Author)