This WRX was stupid fast. Probably over 300hp. At this point we were writing our own notes. We took did “left 3 stay inside over crest into right 4.” There was a large pothole in the middle of the road. The driver went to the outside carrying a lot of speed, got into the loose dirt, and slid off the road right into a tree.
Surprisingly, once they pulled the car out, they were able to drive it back to the shop.
As a seat belt engineer, I decided to check out how the harnesses fared. I thought my shoulder belts must have been loose since my helmet cracked against the harness bar. As it turns out, there was some belt slack. There are folds put in to the belts with specific stitch patterns that will break at a predetermined load. This helps restrict the maximum force transmitted to the occupant. This may have caused my helmet to contact the bar, but since my chest rotated with my head, I didn’t get whiplash. Science!