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Altitude decompression sickness incidence among U-2 pilots: 1994-2010
Gregory L Hundemer1, Sean L Jersey, Rory P Stuart
19th Medical Group, Beale Air Force Base, CA, USA. gregory.hundemer@beale.af.mil
Aviation, Space, and Environmental Medicine
|October 17, 2012
Summary
Decompression sickness (DCS) cases in U-2 pilots increased significantly from 2006-2010, with more severe symptoms. This rise correlated with increased flight hours due to wartime operations, highlighting the need for revised safety protocols.
Area of Science:
- Aviation Medicine
- Aerospace Physiology
- Occupational Health
Background:
- U-2 aircraft pilots face high-altitude cabin pressures, risking decompression sickness (DCS).
- Limited historical data exists on DCS incidence within the U-2 pilot community.
- This study investigates temporal changes in DCS rates and types among U-2 pilots.
Purpose of the Study:
- To analyze the incidence and characteristics of DCS in U-2 pilots from 1994-2010.
- To identify trends in DCS occurrence and severity over time.
- To correlate DCS rates with operational tempo and flight parameters.
Main Methods:
- Compiled a database of all U-2 pilot DCS cases (1994-2010).
- Analyzed cases by occurrence date and experienced symptoms.
- Calculated DCS incidence rates using flight data.
Main Results:
- 73 DCS cases documented between 1994-2010.
- Annual DCS cases increased from 0-5 (1994-2005) to 6-10 (2006-2010).
- More severe (neurologic, pulmonary) cases rose, with DCS risk per flight increasing from 0.076% to 0.23%.
Conclusions:
- DCS remains a significant risk for U-2 pilots.
- Increased operational tempo correlated with higher DCS incidence and severity.
- Recommendations include modifying cockpit pressurization and limiting exposure duration/frequency.
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