SPH-4 U.S. Army flight helmet performance, 1972-1983.

Injury data were obtained from the U.S. Army Safety Center for the occupants of U.S. Army aircraft who were both wearing aviator helmets and involved in duty-related aircraft accidents, for the period beginning on 1 January 1972 and ending 1 January 1983. The injury data were correlated with the physical condition of the involved helmets, examined by the authors under an Aviation Life Support Equipment Retrieval Program. Each helmet's performance was evaluated with regard to current injury prevention capabilities and potential improvements for future helmet design. For consistency, only the 208 SPH-4s in the data base were fully analyzed. Combat damaged helmets were excluded from this analysis.

Helicopter pilot back pain: a preliminary study.

Because of the high prevalence of back pain experienced by U.S. Army helicopter pilots, a study was conducted to ascertain the feasibility of reproducing these symptoms in the laboratory. A mock-up of a UH-1H seat and control configuration was mounted to a multi-axis vibration simulator (MAVS). Eleven subjects were tested on the apparatus for two 120-min periods. During one period, the MAVS was programmed to reproduce vibrations recorded from a UH-1H in cruise flight. The subjects received no vibration during the other test period. All subjects reported back pain which they described as identical to the pain they experience during flight, during one or more of their test periods. There was no statistical difference between the vibration and nonvibration test conditions (p greater than 0.05) in terms of time of onset of pain or intensity of pain as measured by a visual analog scale. It appears the vibration at the frequencies and amplitudes tested plays little or no role in the etiology of the back symptoms reported by these pilots. It is proposed that the primary etiological factor for these symptoms is the poor posture pilots are obliged to assume for extended periods while operating helicopters.