Aircraft Evacuations through Type-III Exits I: Effects of Seat Placement at the Exit

Civil Aerospace Medical Institute1995PDFTech ReportMcLean, G.A.George, M.H.Chittum, C.B.Funkhouser, G.E.Civil Aeromedical InstituteUnited States. Office of Aviation MedicineCivil Aerospace Medical InstituteUnited StatesAir transportation crashesAircraft cabinsEvacuationEmergency exitsSeatsPerformance testsHuman subject testingAircraft accidentsAirplanes--EvacuationAirplanes--SeatsPerformance--TestingAircraft cabins--Design and constructionDOT/FAA/AM-95/22Simulated emergency egress from Type III over-wing exits was studied to support regulatory action by the FAA. Passageway width and seat encroachment distance adjacent to the Type-III exit were the major variables of interest.Methods. Two subject groups of differing mean ages were employed in a repeated-measures evaluation of different passageway widths leading to the exit in the CAMI aircraft cabin evacuation facility. Main effects of passageway width and seat encroachment distance on egress rates were determined using analysis of variance (ANOVA).Results. Main effects were found for passageway width (p <.001), seat encroachment distance (p<.001), and subject group (p<.001). The passageway width resulted from slowed egress at 6 and 10 inch wide passageways relative to 13, 15, and 20 inch passageways; seat encroachment effects were found for maximum seat encroachments but not midpoint and minimum encroachment distances. The subject group effects were found to result from a general increase in egress time for the older subject group.Conclusions. The placement of seat assemblies -at the Type-III exit has significant effects on passenger egress through the exit opening. Narrow passageways and/or large encroachments of the seat into the area of the exit opening delay egress significantly, Relative to the younger subjects, older subjects were found to have a general increase in egress times at all seat placement configurations that did not appear to worsen as the access route to the exit was made more restrictive.119