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Advanced Forensic Engineering Analysis of a School Bus/Tractor Trailer Crash

Richard M. Ziernicki, Ph.D., P.E., F 308
William H. Pierce, P.E., C 846
Angelos G. Leiloglou, M. Arch.


This paper presents advanced techniques used to reconstruct a motor vehicle accident involving a fully loaded semi and school bus with thirty young students.

The accident investigation included analysis of the physical evidence using photogrammetry and high definition laser scanning, application of engine control module (ECM) and global positioning system (GPS) data, and analyzing onboard video footage from the bus.

Momentum-based crash simulation software, PC-Crash was used to simulate the accident. The simulation data was compared with National Transportation Research Board (NTSB) data and with the onboard bus video footage. Further, rigid-body kinematic equations were used to determine occupant kinematics (velocities) and dynamics (accelerations).

Multiple graphics are used to demonstrate the accident reconstruction and occupant kinematics
and dynamics.

Published By


Journal of the National Academy of Forensic Engineers
June 2016