Effects of Weight and C.G. Location of Head- Supported Devices on the Neck Loading

A comprehensive study of the effect of Head-Supported Devices (HSDs) on the neck loading during helicopter accidents is presented. The new Articulated Total Body (ATB) model which treats the neck as a deformable segment is used for crash simulation. Several human and manikin subjects are considered under different crash scenarios. Simulations are theoretically designed to include a wide range of HSDs by changing their weight and C.G. (center of gravity) locations relative to the head and studying the effects of these changes. Since HSDs are only theoretically included in the model, detachment of specific jettable devices, used in most military applications, has not been modeled in the study. Hence, two typical jettable devices are modelled and selected simulations are repeated and compared not only to provide a measure of accuracy for the original results but also to see the effect of separation of these devices from the helmet.