Running with doubles: How North America’s safest fleet navigates with two 53-foot trailers

Bison Transport operates twin 53-foot trailers in Canada, and generally has lower rates of incidents than with single trailers.

Whether you call them twins or doubles, the debate about longer and heavier trucks in the U.S. has been ongoing for years, with each side staking out clear battle lines. The latest skirmish has been over efforts to turn double 28-foot pup trailers into 33-foot pup trailers. Critics say they are not safe; proponents say they increase productivity and save wear and tear on roads.

The truth is probably somewhere in between yet, seems particular hard to find. This despite the fact that in some states it is legal to operate with three pup trailers pulled by a single tractor, or even what is known as a Rocky Mountain Double – a longer trailer, usually 48 foot in length with a shorter pup trailer in the back. A few states also allow full 53-foot doubles.

According to Gail Rutkowski, executive director of NASSTRAC, a coalition of shippers, the tonnage of goods shipped is expected to grow more than 40 percent over the next 30 years. To transport those goods will require more trucks and drivers – unless the trucks and drivers become more productive.

“That is where twin 33s enter the picture,” she wrote. “Twin 33s are tandem trailers of 33 feet in length each. Twin 28s have become a common sight, as they are currently allowed on the national highway network. Some states permit goods to be transported in triple 28s, and others even permit twin 53s on their roadways. Twin 33s, however, can only operate in 20 states. We need to allow them in all 50 states.”

Rutkowski cites efficiency and less wear and tear on infrastructure as benefits. “If twin 33s could operate in all 50 states, trucking companies and others involved in freight transport could reap even greater benefits in efficiency, with consumers being the ultimate winners. The reduction in fuel consumption, congestion, wear and tear on the roads, and pollution will benefit everyone,” she wrote.

Trevor Fridfinnson, COO of Winnipeg, Canada-based Bison Transport, tells FreightWaves the use of double 53s have been beneficial his fleet. Bison has run the trailers primarily through Manitoba, Saskatchewan and Alberta “as a primary application in our network.” The fleet will run about 35 million miles this year, or 21% of its total miles, using this configuration.

“We have seen this as a progressive step, certainly for our business, but also for the industry,” Fridfinnson says, noting that Bison is a supporter of longer trucks operating throughout North America.

As to claims that longer trucks are unsafe, Fridfinnson says it comes down to training and picking the right drivers. “Because it is a larger vehicle … if you have an incident, it can cost more because you have twice the cargo, but our incidents have been less,” Fridfinnson points out.

FMCSA SAFER data shows that in its U.S. operations, which do not run the longer doubles, Bison had just 7.7% of its vehicles placed out of service in the past 24 months versus a national average of 20.72%. Its vehicles also have been involved in just 35 reportable crashes during that timeframe, with only 16 resulting in injury. There have been no fatalities.

“The number of incidents per million miles [for Bison’s doubles] is less than single trailers,” he says. “There are a number of factors, number one is the driver.”

Bison operates 1,371 power units with 1,626 drivers, according to its FMCSA SAFER account. The Truckload Carriers Association has recognized Bison as the winner of its Fleet Safety Award as North America’s safest fleet 10 times, including nine years in a row, in the large carrier division.

Clearly safety is not an issue, and when it comes to running doubles, it starts with choosing the right drivers. Fridfinnson says this application requires a “higher capability of driver,” but it also involves choosing the right operations, running roads that are familiar, and getting the drivers home nightly.

That last part requires network optimization and finding the right freight mix.

“You have to have a certain amount of density in lanes, and [sometimes] even take business that may not fit into [traditional] linehaul models,” Fridfinnson notes.

Building the proper network and scheduling takes time and adds cost, Fridfinnson points out, but it also pays off with more productive vehicles and drivers moving twice the freight. While he declined to provide any specific numbers, Fridfinnson did say that it is not a straight calculation.

“It’s not as simple as a 2-for-1 tradeoff,” he says. “You do have the reduced fuel economy of the truck compared to hauling just a single trailer; you have higher driver wages; and you have higher maintenance costs with higher horsepower, plus the costs of the dollies and higher costs to align shipments.”

There is a cost benefit, he acknowledges, noting that it may be closer to a 1.5-for-1 tradeoff.

Drivers themselves must complete additional certifications and a yearly “renewal” PBIC course to maintain their certification. But the biggest obstacle to making double trailers work is not the equipment or the cost, but rather the aligning of the loads, and ensuring the vehicles are moving into areas and facilities that can handle the added length.

“If only a single truck and trailer can access an area, then there is another cost to handle the P&D to deliver the trailer,” Fridfinnson points out, noting that building the freight network was actually the hardest part. “It’s a big part of it and probably the one part that has required the most investment.”

“In a perfect world, you’d have a customer shipping the same amount of freight in the same directions each day,” he adds, but “at the end of the day, they are still individual trailers.”

Where loads can be aligned, though, the benefits are worth the investment. Fridfinnson points out to make it ultimately work requires not just loads moving in one direction, but having return loads that match up timewise. “There’s a real coordination of efforts needed,” he says.

Bison used to run 53-foot doubles in North Dakota before they were outlawed, in what Fridfinnson says was more likely due to competitive reasons than for safety, but Bison continues to support reevaluating their use.

“It seems there is an opportunity here that needs more education,” Fridfinnson concludes.

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Brian Straight

Brian Straight covers general transportation news and leads the editorial team as Managing Editor. A journalism graduate of the University of Rhode Island, he has covered everything from a presidential election, to professional sports and Little League baseball, and for more than 10 years has covered trucking and logistics. Before joining FreightWaves, he was previously responsible for the editorial quality and production of Fleet Owner magazine and Brian lives in Connecticut with his wife and two kids and spends his time coaching his son’s baseball team, golfing with his daughter, and pursuing his never-ending quest to become a professional bowler.

One Comment

  1. The infrastructure argument is bull. Its all about paying less to ship and passing the cost of wear and tearplus fuel to eother the carrier or o/o