As accident reconstructionists, we strive to explain the circumstances leading up to a collision and the vehicle dynamics of the collision. In doing so, we’ve uncovered insurance fraud in some of our cases where the investigation has actually shown that the collision could not have taken place as claimed.
One such case was a claim that a parked car had been heavily side-swiped by another passing car during the night. The frontal airbags had not fired, which would have been consistent with either the car being parked and not running, or the side-swipe not producing the necessary accelerations for the airbags to deploy when the car was running. The false claim of the parked car collision was readily unmasked when the collision data recorder (CDR) (CDR) was downloaded.
The CDR recorded non-deployment events – those in which the airbag software was activated to evaluate a crash pulse even though it didn’t reach the requirements for the airbags to be deployed. The ignition had to be on for these recordings to be made. The CDR in this instance showed that a non-deployment event had been recorded the last time the ignition was on with pre-impact speeds of 40 to 50 mph and a delta V (or speed change due to impact) in excess of 10 mph. The magnitude of such an impact would not necessarily be expected to deploy the airbags but would leave visible collision damage to the vehicle. This data showed that the car was being driven when the damage occurred.
The damage pattern on the side of the vehicle consisted of a double-grooved horizontal indentation more typical of a highway W-shaped guard rail than the damage one could expect from contact by another vehicle.
Having a CDR download analysis performed in a timely manner can be invaluable in providing important information, particularly in questionable claims.
DONALD EISENTRAUT, BSME, P.E., ACTAR is a mechanical engineer at ARCCA, specializing in vehicular accident reconstruction and forensic analysis of crash protection systems and components.