NCJ Number
203989
Journal
Journal of Forensic Sciences Volume: 49 Issue: 1 Dated: January 2004 Pages: 5-10
Date Published
January 2004
Length
6 pages
Annotation
This study examined the effect of physical forces on the human body in vertical freefall in the absence of interference by human behavioral responses in the course of the fall.
Abstract
The study involved observations of an anthropomorphic dummy that represented the "abnormally relaxed" state, dropped repeatedly (nine times) from a height of approximately 65 feet. The study tested the hypothesis that "abnormally relaxed" individuals (e.g., inebriated, suicidal, incapacitated, or dead persons) would fall in a predictably different fashion than more alert individuals due to the absence of a behavioral defense response; this would be expected to result in a distinct pattern of orientation at impact. In addition, this report presents a case study of a possible suicidal jump from 100 feet which was analyzed by the University of Tennessee Forensic Anthropology Center. In all of the nine falls analyzed, the dummy landed horizontally at impact, suggesting that the human body has a tendency to align horizontally during freefall for falls greater than 50 feet. The case study of a suicide jump also found a horizontal orientation of the body. Once falling, humans can do nothing to control the height of the fall, their mass, their kinetic energy, or the nature of the material they are about to impact, and they can do very little to control their velocity; however, humans can change body position in the air in falls from greater heights. Feet-first appears to be the most common position at impact in freefalls when the person is seeking to reduce the impact and injuries from the unintended fall. This report discusses the differences in observed physical injuries between bodies that are horizontal and feet-first on impact. The types of injuries observed can be important in determining whether or not the person was in an "abnormally relaxed" state in the course of the fall. 1 table, 3 figures, and 33 references