Quantitative Methods for Determining U.S. Air Force Crew Cushion Comfort

2006-01-2339

07/04/2006

Event
2006 Digital Human Modeling for Design and Engineering Conference
Authors Abstract
Content
The detrimental effects of prolonged sitting during long-duration flights include deep vein thrombosis, pressure sores, and decreased awareness and performance. However, the cushion is often the only component of the ejection seat system that can be modified to mitigate these effects. This study investigated the long-duration effects of sitting in four ejection seat cushions over eight hours. Subjective comfort survey data and cognitive performance data were gathered along with comparative objective data, including seated pressures, muscular fatigue levels, and lower extremity oxygen saturation.
Peak seated pressures ranged from 1.22–3.22 psi. Oxygen saturation in the lower extremities decreased over the eight hours. Cognitive performance increased over time regardless of cushion with the exception of the dynamic cushion, which induced a decrease in performance for females. Muscular fatigue increased throughout the eight hours regardless of cushion, with the exception of the dynamic cushion which promoted muscular recovery. Subjective comfort levels declined over the eight hours. Subjective measures correlated with objective parameters for the static cushions. Tradeoffs in performance and fatigue mitigation were apparent in the dynamic cushion which also highlighted differences between genders. These results will be used to develop cushion design guidelines, both to prevent deep vein thrombosis and to promote comfort for long-duration use.
Meta TagsDetails
DOI
https://doi.org/10.4271/2006-01-2339
Pages
12
Citation
Parakkat, J., Pellettiere, J., Reynolds, D., Sasidharan, M. et al., "Quantitative Methods for Determining U.S. Air Force Crew Cushion Comfort," SAE Technical Paper 2006-01-2339, 2006, https://doi.org/10.4271/2006-01-2339.
Additional Details
Publisher
Published
Jul 4, 2006
Product Code
2006-01-2339
Content Type
Technical Paper
Language
English