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Pulmonary Effects from a Simulated Long-Duration Mission in a Confined Cockpit.
Aerospace Medicine and Human Performance
|September 20, 2017
Summary
Sedentary, long-duration missions in confined cockpits significantly reduce pulmonary function. These effects, observed in pilots wearing flight gear, highlight potential operational concerns in similar environments.
Area of Science:
- Aerospace Medicine
- Human Physiology
- Occupational Health
Background:
- A U-2 fatigue study provided data on pulmonary function changes after simulated long-duration missions.
- Subjects experienced 12-hour seated exposures in a hypobaric chamber under two mission configurations.
Purpose of the Study:
- To compare pulmonary function before and after prolonged sedentary exposure in a confined cockpit.
- To assess the impact of different breathing gases (100% oxygen vs. air) and altitudes on pulmonary metrics.
Main Methods:
- Ten subjects underwent simulated missions in a hypobaric chamber.
- Pulmonary function was measured using forced vital capacity, forced expiratory volume in 1 second, peak expiratory flow, and FEV1/FVC ratio.
- Two conditions were tested: full pressure suit with oxygen at 15,000 ft and standard flight gear with air at 8,000 ft.
Main Results:
- Significant declines were observed in all four pulmonary function metrics after 12 hours.
- Declines ranged from 2.7% to 13.9% across the measured parameters.
- These declines occurred irrespective of the breathing gas composition or altitude simulated.
Conclusions:
- Acute, sedentary exposure in confined cockpits leads to measurable pulmonary function decrements.
- The observed pulmonary effects appear independent of oxygen percentage in the breathing gas.
- Findings suggest potential operational implications for missions involving prolonged inactivity in confined environments.
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