On Saturday, June 2, 2018, Aaron Kiefer’s volunteer crew of crash testers, conducted another round of crash testing with his TrailerGuard System consisting of a polyester webbing Safety Skirt connected to his aluminum Rear Reinforcement Attachment (which strengthens the existing rear underride guard).
Crash Test #1 showed some Passenger Compartment Intrusion (PCI), which means the people in the car would have been injured. Analysis of the results showed that the webbing was likely too low and not able to catch the car.
Crash Test #2, on the other hand, was very successful: no PCI. The car was damaged from the collision but did not go under the trailer and rebounded back. 35 mph Delta-V force, 31 mph impact speed
Aerial view from a drone:
Q. What does it mean that the air bags did not deploy?
A. The acceleration was low enough that the car decided that it didn’t need them. So the crash pulse was “long” due to the flexibility/energy absorbing of the webbing. According to the air bag control module report, the car deployed the driver seat and passenger seat belt pretensioners. However, the severity of the crash was judged below the threshold to require the frontal air bags. This is due to the fact that the deceleration was achieved over a long duration (over 200 ms) and that the decleration rate was low.
Q. So, how would occupants have fared?
A. The occupants would have been fine in this 30+ mph collision since PCI was avoided and the energy was absorbed by the webbing and the vehicle structure. the threshold for air bag deployment of a vehicle of this type striking a solid object is 10-15 mph.
Crash testing — especially without the backing of corporate R&D resources — is time-consuming but well worth the effort. Imagine where we would be in terms of preventing devastating truck underride if we all collaborated to get the job done!
