Mechanical Engineer Evaluates Cause Of Roller Coaster Injury

This case involves a child who suffered head injuries while riding a roller coaster. The boy met the height and weight requirement for the coast in question. While the roller coaster went back and forth, the child hit his head several times on the seat and head restraint. The child suffered a concussion from this incident and was unable to attend school for several months, requiring he be held back. An expert in mechanical engineering with experience in roller coaster design was sought to evaluate if the child was injured as a result of flawed seat and harness designs or whether improper height/weight requirements for the roller coaster affected the safety of the ride.

Question(s) For Expert Witness

1. Are you familiar with roller coaster engineering and mechanisms?

2. How can improper height and weight requirements for roller coasters affect the safety of the ride?

Expert Witness Response E-101108

I am a mechanical engineering professor and engineering education/research leader familiar with roller coaster engineering and mechanisms. My institution has organized and hosted student groups working on roller coaster design and safety. My preliminary review of this case leads me to believe that this is not a situation where an amusement ride failed to operate as designed or programmed due to some mechanical device or linkage failure. Instead, this is a case that involves biomechanics in which the designed bi-directional motion of the amusement ride induced head and neck motion of a certain sized rider that was not appropriately constrained and/or cushioned by the restraint/seat design. I have served as an expert for similar situations in the past in which serious physical injury resulted from the improper design, manufacture, or operation of a mechanical device. I am not a medical doctor that can evaluate the severity of certain types of head injuries, but I am very qualified to provide expertise on the mechanics and biodynamics involved that would lead to certain levels of head/neck accelerations and impact forces.