Studies conducted at the FAA Civil Aeromedical Institute have shown that when used in aircraft, automotive Child Restraint Devices (CRDs) do not always provide the level of safety desired. Various factors that contribute to poor performance, such as seat belt anchor location, cushion stiffness, and CRD design features, were evaluated by a dynamic impact test program. To efficiently continue the research, a computer model was developed using MADYMO. Results of two of the impact tests were used to validate the model. Both test configurations utilized a typical commercial transport airplane passenger seat and a popular automotive CRD. These tests were considered representative of the extremes of CRD and occupant kinematics due to variance in seat belt anchor location. Details are presented of the test parameters and geometry, as well as cushion and restraint system properties. Test and modeling results for these two impact conditions are summarized and compared. Parametric studies were then conducted that used the model to investigate the effect of cushion stiffness, belt anchor spacing, and initial belt tension.