Carl F. Thelin

CxSI: Highway

My book and this blog contains car-crash stories based on my real career of crash scene investigator. The investigations were done to enable me to testify in court to answer the question: Which driver or car-maker was responsible for the crash and the severity of the injuries? Human-interest aspects of these

stories are revealed in court testimony found elsewhere in the book.

In order to qualify (convince the Judge) that I was an expert witness, it was necessary to show my credentials. This did it…

This was a 60 mph pole crash I did early in the development of the car crash towing system at Cornell Aeronautical Laboratories. I needed to convince our sponsor, the National Highway Traffic Safety Administration (NHTSA), that our computer control system and the complex and powerful towing system could do this. 

   The car was just a scrap car, like the others we used for practice while tuning things.

   Right after this crash, which sounded like a shotgun blast, I shouted, "Even the cockroach in the trunk would have died."

    Out in the real world, people would see a wrecked car that had hit a pole or a tree at 30 mph and exclaim, "He must have been going 60!" 

   Today (2010) almost any car could be run into a flat barrier at 30 mph where the damage would be limited to the structure ahead of the windshield. Typically the WS glass would be broken only by the expansion of the airbags. 

  At CAL, we stopped attaching the steel pole to the concrete barrier when NHTSA determined that the injurious force to the occupant dummies was less than that during a flat barrier impact. The pole crash looks worse because of the deep penetration. However, that longer ride-down allowed for more force dissipation. 

LOOK at the Table of Contents.