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!
NBC News received a letter from the Truck Trailer Manufacturers Association about the Today Show investigative report on Side Underride. After further investigation, NBC News added this to their article on the report:
Update and correction: After the publication of our story, we received a letter from the Truck Trailer Manufacturers Association (TTMA), which argues that our report overstated the simplicity of the side guard fix and that prototypes have been technical and commercial failures. TTMA made the same argument to NHTSA in a letter we referenced in our report, which you can read here. They also told us that TTMA has not made any political donations to lawmakers on the issue of side underrides, including to Senator Thune. In response to other points made by TTMA, we have updated our online report with TTMA’s response that guards in Europe are focused on protecting bicyclists and pedestrians, not automobiles and that NTSB said injuries and deaths “could” be reduced by side guards, instead of “would.” We also have updated campaign finance data, broken out donations from the trucking sector of the transportation industry, and corrected the period during which those donations were made.
I previously wrote about the TTMA’s May 13, 2016 letter to NHTSA about side guards. Read it here.
Despite the TTMA’s objections to the report, the fact remains that almost as many people die from side underride crashes each year as from rear underride crashes. And, furthermore, I have seen with my own eyes the difference that side guards can make in stopping deadly underride.
Will we let the technical and commercial failures of side guard prototypes in the past stop us from keeping at the task of solving this problem? I thank God for people like Aaron Kiefer and Perry Ponder who have kept at it until they successfully proved what human ingenuity could do to save lives.
Note: In fact, Europe’s side guard standards are designed to protect pedestrians and cyclists — which the U.S. should do, too! But Europe does not require the prevention of cars from underriding trucks. I have been in communication with a global automotive regulation specialist, and I hope that what happens here in the U.S. will have a ripple effect globally.
