AngelWing Can Prevent Side Underride

Aftermarket technology that attaches to the sides of trucks can make underride crashes more survivable.

Angel Wing Side Underride Guard
The AngelWing side underride guard, installed for a crash safety test at the Insurance Institute of Highway Safety. Photo courtesy of Perry Ponder.

In August 2017, a 2009 Chevrolet Malibu was observed plowing into the side of a 53-foot-long dry van trailer at 40 mph. If this side underride truck accident had occurred in the real-world, the occupants of the Chevrolet would have suffered catastrophic injuries or death. But the Malibu was equipped with an aftermarket device called the AngelWing side guard, which prevented the car from going underneath the truck trailer during the crash test in question. 

Moreover, “the car’s airbags and safety belt properly restrained the dummy in the driver seat,” noted the Insurance Institute for Highway Safety (IIHS) in a press release. “Our tests of the AngelWing show that measures to reduce the side underride problem are within reach,” added David Zuby, IIHS executive vice president and chief research officer. “Broader use of devices like this one, combined with continued improvements to rear underride guards, would go a long way toward reducing deaths in large truck crashes.” 

That’s what safety advocates like Marianne Karth and Lois Durso are hoping. (Karth was the victim of a rear underride crash, one which took the lives of two of her daughters; Durso lost her daughter in a side underride accident in 2004.) Today both are working to raise awareness about the dangers of truck underride—side underride accidents, rear underride accidents and front underride accidents—and advocating for the passage of the bipartisan Stop Underrides Act of 2017

Meanwhile, independent developers and truck trailer manufacturers alike are working on technologies designed to minimize the injuries and deaths suffered in underride accidents. Perry Ponder is one of these developers, whose AngelWing side guard is available via Air Flow Detector

In the following interview, we talked with Ponder about his AngelWing and why he believes legislators haven’t yet mandated side underride guards on big trucks, despite the known risks of underride. 

What inspired you to start working on the AngelWing side underride guard? 

My first job out of college I went to work for a small trailer manufacturer called Terminal Service Company, and one of the first things I worked on was the rear underride guard for the trailers because that was a new standard at that time. Shortly after that I took a job for an accident reconstruction and forensic engineering firm. Those two things have dovetailed together to bring me to where I am developing AngelWing. I have gone from my work as a trailer expert, to expert witness work, to doing development work. 

What is a side underride accident? 

Underride can happen anywhere on the perimeter of a longer truck and it’s just a matter of height difference. The height of the perimeter of a truck, whether it be the rear or side, creates a situation where the areas of a car that are designed to take an impact are bypassed and the collision occurs with parts of the car that are not designed to take the collision, like the windshield. 

When the bumpers are bypassed and the windshield and roof are crushed-in the airbag doesn’t work, the seat belts don’t work for you, and it compromises what is known as the occupant survival space. Of course, it’s important to keep the “safety cage” around you intact. 

Tell me about AngelWing side guards. 

 AngelWing is designed to be retrofittable to your typical box van or box trailer—refrigerated or dry freight—that you see rolling down the road. It’s three different parts and you can put it together in about two hours. We’ve tested it at speeds up to 40 mph, but it will prevent a car from riding underneath a truck at speeds higher than that. 

What materials does AngelWing utilize? 

It’s just plain steel, though we’re experimenting with working in at least some aluminum to make it lighter. 

What have crash tests of the AngelWing side guards revealed? 

In the videos you see the difference between what happens in a crash with a side underride guard and without. The difference is you have a bumper-level collision out in the front of the vehicle that keeps the heads and torsos of occupants away from the edge of the trailer. If the underride guard is not there the edge of the trailer is essentially a guard rail and the first impact occurs with the windshield and roof of the vehicle. In that situation it allows direct contact between the trailer and the heads of occupants. 

Did the IIHS sponsor the testing? 

They had a trailer that was left over from some of the rear underride guard testing that they had done, so they provided the trailer and I provided the guard. It was at their request that we did the testing, first at 35 mph and then a subsequent test was done at 40 mph.   

Requiring side underride guards is an idea that has been around a long time. Why do you think they haven’t been mandated yet? 

It’s industry resistance. 

What are the concerns among trailer manufacturers in regards to side underride guards being mandated? 

There are particular concerns that have been voiced and they are related to weight and technological feasibility, but as somebody who has designed trailers and understands mechanical engineering and understands the structural engineering behind it, there’s no reason for technological concerns. 

The extra twenty or so inches it [the guard] protrudes from the bottom of the trailer is not a hazard for hanging up or impeding operations. As for weight, most tractor-trailers cube out or use up all their space before they ever get close to reaching the 80,000 pound weight limit for the combination of tractor and trailer. 

How does one purchase AngelWing side underride guards? 

They are being sold through Air Flow Deflector, which is manufacturing and selling [the guards]. It was a natural fit for me to join up with them as they also sell fuel-saving, aerodynamic air deflectors. They have also been in the business of underride guards for cyclists and pedestrians.

You Might Also Appreciate:
Making Underride Accidents Less Deadly