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Manned Testing of Pressure Fluctuations Involved in Naval Aviation Physiological Events

Descriptive Note:

Technical Report,30 Mar 2018,29 Mar 2019

Corporate Author:

U.S. Navy Experimental Diving Unit Panama City United States

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The U.S. Navys premier tactical aircraft platforms, the FA-18 and EZ-18G, are experiencing physiological episodes Phys Eps of unexplained rapid cockpit pressure fluctuations. Some of the Phys Eps have resulted in naval Aviator injuries collectively termed Physical Events PEs. According to the current Clinical Practice Guidelines, Aviation PEs occurring in the presence of rapid cockpit pressure fluctuations often result in aviators and aircrew being treated with hyperbaric oxygen therapy. Unfortunately, because the root cause remains elusive, it is unclear what pathology is being treated with hyperbaric oxygen. The Navy Experimental Diving Unit NEDU conducted the first-ever human subject research utilitzing a unique purpose-built pressure vessel for human occupancy PVHO hypobaric chamber that could achieve rapid pressure fluctuations similar to those seen in the cockpit. The primary objective of this study was to elucidate whether manifestations resembling PEs would occur subsequent to rapid pressure oscillations in the absence of confounding factors such as breathing system resistance and to characterize any physiological symptoms that may result. There were no diagnosed cases of decompression sickness, arterial gas embolism, physiological events, or neurological changes secondary to exposure to the experimental rapid pressure fluctuations. Additionally, there was no evidence of a decline in cognitive function, presence of nystagmus or eye movement abnormalities ....This study suggests that the root cause is multi-factorial and further research, particularly focused on the man-machine interface of the environment control system and breathing system, is recommended.

Subject Categories:

  • Stress Physiology

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