Carry Engineer Crash Tests Truck Bottom Ranger Trailer

Carrie’s Aaron Kiefer has spent years developing hardware that can be bolted to truck trailers to try and prevent cars from sliding downhill.

The goal is to prevent what is known as undercarriage, where the hood or trunk of a truck passes under the truck, then crashes through the windows in the passenger compartment. In under-collision situations, seat belts, airbags and crash zones that manufacturers make in cars and SUVs to protect people aren’t given a chance to work.

Kiefer, an engineer who makes a living from accident rebuilding, tested the latest version of his bottom guard Tuesday with a Nissan Altima being towed at nearly 35 mph in the side of a box-trailer.

“We all hope to see the car bounce off the trailer,” he said, as he and a team of volunteers made final preparations at the State Highway Patrol test track south of Raleigh. “But this is R&D…”

Kiefer began designing underbody guards after consulting on cases involving fatal accidents that should have been escaped except that the car or SUV had fallen under the truck. Develop something he calls SafetySkirtwhich are designed to block side undercarriage but look like trailer skirts already widely used to improve aerodynamics.

On Tuesday, he was testing a new design that combined a polyester webbing along the side of the trailer and a series of steel cross clips underneath. The system is designed to be modified to fit current truck trailers without adding much weight.

The test was straightforward: a Toyota Tundra was pulling away from the trailer and pulling the Altima with a tow rope toward the truck on the other side. The car, a flood damaged donation, had a crash test dummy on the steering wheel, countertops on the front wheels to keep it straight and a rooftop remote control to operate the brakes if something went wrong.

Kiefer took about a dozen of these tests and spent about $100,000 on a project he calls “Labour of Love.” He didn’t convince anyone to buy or manufacture his guards, but said he had just heard that Utility Trailer Manufacturing Company became the first company to offer Optional undercarriage for new trailers.

“That’s kind of the way the industry works. They say it can’t be done. They say it’s too expensive. They have all these problems with it. But then they’re going to come up with their own product.” And that’s great, because it means there’s a move toward custodial. So I fully expect within a few years the new trailers will have these technologies.”

Carey engineer Aaron Kiefer assesses the damage to his prototype undercarriage after towing a Nissan Altima at 35 mph alongside a box-trailer. The Keifer system is designed to prevent fatal side collisions. Travis Long

It is believed that the number of deaths from plane crashes is underestimated

Raleigh’s Marianne Karth, who lost two teenage daughters in a 2013 plane crash, said Utility’s decision to offer an optional side guard was “huge”.

“This paves the way for others, because they have to be competitive,” Karth said.

Karth, who lives in Raleigh, has spent years speaking at conferences, going on television and radio and lobbying members of Congress, government regulators and the trucking industry about the need to prevent crashes. About six years ago, I collaborated with Louis Dorseauwhose 26-year-old daughter was killed in a crash downhill near Chicago in 2004.

Karth, Dorso and their husbands were among the volunteers who helped Kiefer test his guard on Tuesday. Also on hand were about two dozen members of the State Highway Patrol, mostly units that organize trucking or rebuild crashes.

An estimated average of 219 people were killed each year in plane crashes in the United States in the decade to 2017, according to A report from the State Audit Bureau.

But the GAO concluded that late deaths are likely underreported, because law enforcement agencies do not have a standard definition of abuse and some crash reporting forms have no place to report them (the standard form in North Carolina does).

The crash test finished in an instant

Congress addressed the most common type of undercarriage crash last fall through the Infrastructure Act, This requires manufacturers to equip trucks and trailers with rear bumpers Strong enough to prevent the car from sliding under 35 MPH. The law also directed the National Highway Traffic Safety Administration to study measures that prevent cars from sliding off the sides of trucks and trailers, and “if necessary, develop performance standards for side undercarriages.”

Kiefer hopes that one day his rangers will be among those trucking companies buy to modify their trailers. Tuesday’s test was an encouraging move.

After a false start (someone left the emergency brake on the Altima), the test ended in an instant. Sensors at the point of impact indicated that the car was traveling at 34.5 mph when it hit the side of the trailer and bounced back. The hood folded and the grill and headlights crashed. But the windshield remained intact (except for the pre-existing crack), and the test dummy sat in one piece behind the airbag.

A crash test dummy sits in a Nissan Altima with an airbag deployed after Carey engineer Aaron Keifer’s prototype tests of a tractor-trailer truck at the NC State Highway Patrol test track Tuesday, Sept. 13, 2022. Keifer system designed to prevent fatal underride side crashes. Travis Long

“The car would be considered assembled, I’m sure,” Karth said. “But it didn’t go past the windshield. It didn’t flatten the roof. The airbag was triggered, and these things don’t happen when there’s no bumper in the car.”

Within minutes, Kiefer and his crew began dismantling the lower visor, and noticed some twisting in one of the crossbeams. He said he’d like to make those beams stronger in the middle of the clip so that the guard would hold up when hitting at 40 or even 45 mph.

But at 35 mph, the Ranger passed Tuesday’s test.

“The entire frontal area of ​​the car absorbs energy. The side of the trailer has never come close to the windshield.” “A lot of space to survive.”

This story was originally published September 13, 2022 5:58 pm.

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Richard Stradling covers transportation for The News & Observer. Planes, trains and cars, as well as ferries, bikes, scooters and just a simple walk. Also, hospitals during the coronavirus outbreak. He’s been a reporter or editor for 35 years, including the last 23 years at The N&O. 919-829-4739,

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