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Quantitative Methods for Determining U.S. Air Force Crew Cushion Comfort
ISSN: 0148-7191, e-ISSN: 2688-3627
Published July 04, 2006 by SAE International in United States
Annotation ability available
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.
CitationParakkat, 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.
- Pint, S. M. Pellettiere, J. A. Nguyen, C. “Development of Objective Test Methods for Determination of Ejection Seat Cushion Comfort,” SAFE Association Conference Proceedings 2002
- Stubbs, J. Pellettiere, J. A. Pint, S. M. “Quantitative Method for Determining Cushion Comfort,” Paper # 2005-01-1005, Society of Automotive Engineers (SAE) 2005
- Cohen, D. “An Objective Measure of Seat Comfort,” Aviation Space Environmental Medicine 69 410 4 1998
- Hearon, B. F. Brinkley, J. W. “Effect of Seat Cushions on Human Response to +Gz Impact,” Aviation Space Environmental Medicine 57 113 21 1986
- Severance, C. M. “B-2 Aircrew Seat Comfort Cushion Design and Development,” Northrop Grumman Corporation Palmdale, CA 25 32 SAFE Association Symposium Proceedings 1997
- Pint, S. M. Internal Memorandum, ACES II Seat Cushion Comfort Interview with LtCol Lex Brown AFRL/HEC 2 Aug 99
- VanIngen-Dunn, C. Richards, M. K. “Feasibility of Reducing Incidence of Low Back Pain in Helicopter Pilots Using Improved Crewseat Cushions,” Armstrong Laboratory Wright-Patterson AFB OH 1992
- Perry, C. E. “Evaluation of a Proposed B-2 Seat Cushion by +Gz Impact,” Armstrong Laboratory Wright Patterson AFB OH 1997
- Perry, C. E. Nguyen, T. Q. Pint, S. M. “Evaluation of Proposed Seat Cushions to Vertical Impact,” SAFE Association Symposium Proceedings Reno NV 2000
- Cantor, A. “Live Qualification of the Lumbar Pad and Pulsating Seat Cushion for the S-3A Escape System,” Naval Air Development Center (NADC) Warminster PA 1974
- Ferguson-Pell, M. W. Cardi, M. “Pressure Mapping Systems for Seating and Positioning Applications: Technical and Clinical Performance,” Helen Hayes Hospital, Center for Rehab Technology, RESNA International 92 219 221 1992
- Ferguson-Pell, M. W. Cardi, M. “Pressure Mapping Systems,” 27 32 1992
- Oudenhuijzen, A. J. K. Krul, A. J. “An Overview of Subjective Test Results for Comfort on Different Seat Cushions for Ejection Seats,” TNO 2005