Investigating the (length) constraints imposed by the Front Underrun Protection Regulation

Previous analysis was based on the assumption that a front underrun protection fitted to an extended length vehicle would deflect under test loads by the maximum 400mm permitted by the current rules. This more detailed examination has identified that most of a small sample of production front underrun protections for which data was available was considerably stiffer than the minimum required. Using a front underrun protection of this stiffness would allow an extension in length of 800mm without amending the current rules. However, as those rules were developed for flat fronted truck designs, some sub-optimal conditions remain.