MULTIBODY DYNAMICS OF AIRCRAFT OCCUPANTS SEATED BEHIND INTERIOR WALLS

To improve aircraft crash safety, conditions critical to occupants sur vival during a crash must be known. In view of the importance of this problem, studies of post-crash dynamic behavior of victims are necessa ry in order to reduce severe injuries. In this study, crash dynamics p rogram SOM-LA/TA, incorporating a dynamic model of the human body with a finite element model of the seat structure was used. Modifications were performed in the program for reconstruction of an occupant's head impact with the interior walls or bulkhead. A viscoelastic-type conta ct force model was used to represent the compliance characteristics of the bulkhead. Correlated studies of analytical simulations with impac t sled test results were accomplished. A parametric study of the coeff icients in the contact force model was then performed in order to obta in the correlations between the coefficients and the Head Injury Crite ria. A measure of optimal values for the bulkhead compliance and displ acement requirements was thus achieved in order to keep the possibilit y of a head injury as little as possible. This information could in tu rn be used in the selection of suitable materials for the bulkhead, in strument panel, or interior walls of an aircraft.