Improving Secondary Impact Protection for Freight Locomotive Engineers

A modern freight locomotive designed to the specifications of Title 49 Code of Federal Regulations (CFR) § 229.207 and the Association of American Railroads’ (AAR) S-580 can preserve the space occupied by an engineer in the leading cab in a train collision up to moderate speeds. However, the space preservation does not provide protection against the injuries resulting from secondary impacts resulting from abrupt locomotive deceleration. The criteria for secondary impact protection are established in the Department of Transportation’s Federal Motor Vehicle Safety Standard 208 (FMVSS 208). A prototype Secondary Impact Protection System (SIPS) for locomotive engineers, consisting of an airbag and a deformable knee bolster, was developed and demonstrated under simulated collision conditions, using a dynamic sled test with a 95th percentile anthropomorphic test device (ATD). The airbag developed a tear at the time of maximum pressurization and was unable to slow the ATD sufficiently. However, the SIPS system met nine of the eleven injury criteria limits. The simulation results for the latest airbag characteristics show that the design would meet the FMVSS 208 criteria including compartmentalization without impeding existing cab functional requirements. However, to optimize the modifications to the airbag design, characterization testing followed by sled testing is recommended.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 98p

Subject/Index Terms

Filing Info

  • Accession Number: 01705963
  • Record Type: Publication
  • Report/Paper Numbers: DOT/FRA/ORD-19/09
  • Contract Numbers: DTFR53-12-D-00004; Task 11
  • Created Date: May 10 2019 12:23PM