FM/FM Telemetry of Physiological and Force Data During Military Parachuting and During High Speed Aerial Tow

Abstract

15- and 9-channel FM/FM physiological/force-field telemetry data acquisition systems utilizing microminiaturized signal conditioning modules, IRIG subcarrier oscillators and 220 or 1485.5 MHz transmitters have been utilized to monitor the responses of military test parachutists throughout intentional free-fall parachuting and continuously during highspeed (110-150 KIAS) through-the-air-tow by C-130 aircraft. No in-depth physiological studies of parachutists have previously been conducted and no reference to intentional aerial tow of humans was found in the literature. The objective is to provide better human engineered egress and retardation equipment for the aircrewmember, to describe parachutists physiologically, and to assess biomedical response to aerial tow so that mid-air retrieval systems can be developed for rescuing ejectees over enemy territory. Mean heart rate profile to parachuting exhibits a double peaked curve with the highest values near parachute deployment (157.7 BPM) and second highest rates near landing (155.7 BPM) compared with baseline values of 77.4 BPM one hour pre-jump. Respiratory rate more than doubles during the jump (32.1 BrPM) at deployment when compared with baseline conditions (15.6 BrPM). Total riser forces at parachute deployment average 1632 lbs (8.34 +G(z)), Preliminary air tow data indicate that heart rate increases linearly with speed to 150 KIAS. One subject, who averaged 131.5 BPM at landing during nine parachute descents, had heart rates of 128 BPM at egress during tow, 171 BPM at 110 KIAS, and 182 BPM at 150 KIAS. Thermistors and subjective data indicated no significant chilling after 14 minutes in the air-stream.