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Accident Investigation Animations

Collision Between a Tractor/Semi-Trailer and School Bus
Mountainburg, Arkansas

May 31, 2001
Highway Accident Report

Videos are available in wmv format and were presented at the Board meeting on September 4, 2002 in Washington, D.C.

Disclaimer: Simulations presented below used scene surveys, vehicle and scene testing, vehicle operating characteristics, pictures and witness statements. The depictions do not represent actual lighting and weather conditions at the time of the accident.


Vehicle Dynamics: Five different views of the vehicle dynamics were rendered to show various perspectives of the crash. Prior to exiting the Interstate onto the exit ramp, a fully loaded tractor semi-trailer, with braking deficiencies, had descended a 12-mile downgrade. In the simulations, the initial speed of the loaded tractor/semi-trailer at the top of the ramp was about 33 mph. The tractor/semi-trailer's speed increased to about 48 mph on the ramp's steep downgrade as the brakes faded prior to impact and the truck ran past a stop sign. The school bus approached the intersection at about 50 mph.

Truck Chase Animation


Truck Chase

Video = 723K
This is a chase view of the truck on the ramp as it travels toward the intersection and collides with the school bus in real time.

Bus Chase Animation  

Bus Chase

Video = 545K
This is a chase view of the schoolbus as it approaches the intersection.

Oblique Intersection Animation

Oblique Intersection

Video = 163K
This is an oblique intersection view of the collision.

Truck View Animation  

Truck View

Video = 706K
This is the truck driver's potential front and left views as the vehicle approaches the intersection, displayed in a split screen format.

Bus Split View Animation  

Bus Split View

Video = 361K
This is the bus driver's potential front and front middle views as the vehicle approaches the intersection, displayed in a split screen format.

The simulations were produced on an HVE™ system using EDSMAC4™ SIMON™ and EDGEN™ programs. All of the programs are trademarks of the Engineering Dynamics Corporation. The movies were produced in Adobe Premiere™. The program is a trademark of the Adobe Systems Incorporated.

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