Oevertrychksandningssystemet i Flygplan 39 Gripen: Effekter av Mottrycksvaesten (Positive Pressure Breathing System in JAS 39 Gripen; Effects of Counter-Pressure Jerkin).

摘要

In fighter aircraft positive pressure breathing is commonly used as part of the anti-G ensemble. To optimize G-protection and prevent over-distention of the lungs, increased airway pressure is balanced by applying a counter pressure to the chest. The aim of the study was to investigate the efficacy of chest counter-pressure. Three series of experiments were performed using the anti-G ensemble of the 39 Gripen aircraft (AGE- 39). In the first series 12 subjects were exposed to 20 s G-time profiles up to 8.0 Gz. In the second series 9 subjects were exposed to 20 s profiles up to 9.0 Gz and simulated aerial combat maneuvers (SACM). Impairment of central and peripheral vision, arterial and airway pressures, pressure in the lower portion of the esophagus and chest-wall distension were measured in series 1 and 2. In the third series, 6 subjects were exposed to 20 s profiles up to 7.0 Gz and esophageal pressure was measured in the upper thorax. In all series, two conditions were compared: with and without pressurized chest bladder.