May 31, 2011
Doswell, VA
Animation of Accident Reconstruction
This three-dimensional animated reconstruction shows the accident sequence for a motorcoach departure and overturn on northbound Interstate 95 (I-95) near Doswell, Virginia, which occurred on May 31, 2011 at 4:55 am local time.
This animation illustrates the overall accident sequence from just before the motorcoach departed from the travel lanes until the vehicle was at its final rest position. The roadway and the area of the accident including the guardrail are scale models built from the three-dimensional survey data. The trees are based on photographs of the accident site. The animation depicts the vehicle motion developed through a simulation that was based on the physical parameters of the motorcoach coupled with the evidence of the determined path of the motorcoach, and the damage to the motorcoach and cable barrier. Uncertainties in the vehicle parameters, limited physical evidence and approximations used in the computer models would permit some variation in the calculated motion of the motorcoach while still matching the overall vehicle behavior. The animation does not depict the weather or visibility conditions at the time of the accident. The animation does not include audio.
The animation sequence shows the motorcoach initially traveling in the right hand lane. The motorcoach departs the travel lane to the right, crossing the rumble strips onto the improved shoulder and then departing the 12-foot-wide paved shoulder at an approximate 5-degree angle to the right. The motorcoach continues about 126 ft, and strikes a 3-strand cable barrier post with the right front corner at about a 6.5-degree angle. The cable barrier was located 14.5 feet from the edge of the paved shoulder. The motorcoach continues about 147 ft along the cable barrier and then begins to turn back toward the road. The motorcoach continues to travel about 96 feet when the motorcoach overturns to the right by 180 degrees onto its roof. The motorcoach then slides about 91 feet before coming to rest on its roof.
The animation sequence is shown twice divided by the title "Repeat of Animation Sequence".
Occupant Kinematics Simulation
This simulation shows the general occupant kinematics for a motorcoach run off road and overturn on Interstate 95 (I-95) northbound in Doswell, Virginia, which occurred on May 31, 2011.
This simulation illustrates the general occupant kinematics for four 50th percentile adult male anthropomorphic test devices (ATDs or simulated crash test dummies) in both an unbelted and a lap/shoulder belted condition from just before the motorcoach interacted with the cable guardrail until after its overturn. The occupant kinematics simulation is based on the vehicle motion developed through a vehicle dynamics simulation combining the physical parameters of the motorcoach coupled with the evidence of the determined path of the motorcoach and the damage to the motorcoach. The study was performed to evaluate general occupant kinematics and was not intended to represent the actual motion of specific individuals in the crash. The simulation did not account for intrusion when determining injury. This simulation does not contain audio.
The simulation shows that unbelted occupants were vulnerable to injury during the bus overturn due to impacts with other occupants and impacts with interior surfaces. As the bus overturned onto its roof and the roof shifted laterally and collapsed toward the tops of the seats, occupants were thrown toward the roof and were vulnerable to crushing injuries especially between the intruding roof and the tops of the seatbacks.
Lap/shoulder belted occupants were contained within their seating compartments. This containment reduced injuries due to contacts with other occupants and with interior surfaces. Importantly the extent of the roof crush into the passenger compartment still placed these occupants in a position vulnerable to head and neck injury due to the loss of vertical survival space even when the occupants were restrained and kept in their seating compartments.
The animation sequence is shown twice divided by the title "Repeat of Animation Sequence".
