June 15, 2015

Document: Myths & Facts

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False claims, unsupported statements and contorted or selective reading of safety data are part of the current debate about a modest proposal to extend twin trailers in the less than truckload (LTL) market by five feet.

The issue is important. Facts matter; therefore we must set the record straight about several persistent myths.

Myth – Opponents routinely make claims that twin 33s would run on local roads and create new challenges for local officials.

Fact – Twin trailers do not currently operate on local roads without authorization from the state Department of Transportation. Proposals before the Senate and passed with bipartisan support in the House would not create changes to where twin trailers operate on the national road network. Twin 33s would only operate on roads where twin 28s currently operate.

Myth – Opponents of twin 33 foot trailers purposefully conflate length and weight as if these features of trucks are interchangeable.

Fact – In May, House Appropriators passed language addressing the length of twin trailers and considerable support exists within the Senate. Members of CERT are not advocating for changes to the federal weight standards.

The proposal to extend the length limit on twin trailers in the less than truckload market – from 28-­‐ to 33-­‐feet – does not alter the overall weight limit of 80,000 pounds, nor does it change axle or bridge formula weight limits. LTL carriers typically fill their trucks before reaching the federal weight limits and therefore it would make no sense to seek an increase in weight limits.

Myth – Twin 33’ trailers are a threat to infrastructure or require costly upgrades to bridges, ramps and other features of the national road network.

Fact – The use of twin 33’ trailers would produce savings. The longer wheelbase – with no change in weight – decreases the stress on bridges and increased productivity reduces the number of trucks that are sent out onto the roadways. Both effects improve the longevity of our infrastructure.

Myth – The CERT proposal would “override the laws of many states.”

Fact – Current federal law requiring states to allow the operation of twin 28’ trailers gives states wide discretion to determine appropriate routes on which these trucks can operate, and states may prohibit them from using a route that the state determines may not be safe. This would not change under the legislation. A 2002 report by the National Academy of Sciences recommended that twin 33’ trailers should be authorized to operate nationwide.

Myth – Twin 33’ trailers would have a wider turning radius than most trucks on the road today and therefore create safety hazards or the need for infrastructure upgrades.

Fact – According to the U.S. Department of Transportation twin 33’ trailers actually have a tighter turning radius than a single 53’ trailer configuration, the most common tractor-­‐ semitrailer operating throughout the United States.

Myth – Twin 33’ trailers would present a greater risk for side underride crashes. Or, twin 33’ trailers require greater stopping distances.

Fact – Between 2009 and 2013 these types of crashes accounted for just one percent of all fatal crashes involving a double-­‐trailer truck – an average of one crash per year. The argument is presented without evidence and is a red herring.

Testing demonstrates that stopping distances are not an issue as a result of shifting from 28’ to 33’. The ability to stop is primarily a function of weight and speed not of the trailer length.

Myth – A study by the Multimodal Transportation & Infrastructure Consortium (MTIC) is often erroneously cited. Opponents claim that it shows double-­‐trailer configurations have a

15.5 percent higher fatal crash rate than single-­‐trailer trucks and conclude that any shift in freight from single to double trailer configurations as a result of this increase will cause a higher safety risk to the public.

Fact – Dan Blower, a research scientist with the University of Michigan Transportation Research Institute and project director for TIFA, a truck crash database which the MTIC study relied upon for its safety data, conducted a review of the MTIC study for the American Trucking Associations. The review found that among other significant issues, the crash data in the MTIC study is misleading, uses incorrect math, and misclassifies trucks (inflating the number of double-­‐trailer fatalities).

Myth – It is claimed that multi-­‐trailer trucks have an 11 percent higher fatal crash rate than single-­‐trailer trucks. A 2000 U.S. Department of Transportation study is cited.

Fact – The USDOT study, which looked primarily at double 28’ combinations, actually found that multi-­‐trailer trucks had a three percent lower crash rate than single trailer trucks. Only by assuming that the multi-­‐trailer trucks would operate on more lower-­‐ order roads than they actually do could USDOT produce a theoretical assumption that multi-­‐trailer crash rates might be higher than single-­‐trailer crash rates.

Myth – A move from 28’ to 33’ in the LTL market would take freight off of trains and put it on the highways or would require significant changes to rail cars to accommodate the new trailers.

Fact – The LTL market does not serve the same market as the railroad industry or the truckload shippers. The hub-­‐and-­‐spoke nature of the LTL market keeps trailers in use and not being shipped between facilities. In the fourth quarter of 2014 just 1.7 percent of trailers or containers shipped by rail were 28’ long. Any shift away from rail would have a negligible impact on rail market share or truck miles traveled.

Every year, millions of tons in goods are sent across roads in shipments that don’t quite fit in a 28-­‐ft. trailer, but aren’t nearly enough to require a full 48-­‐ft. or 53-­‐ft. trailer. As a result, more than 6.6 million avoidable truck trips occur every year. This inefficiency is only expected to worsen: over the next decade, less than truckload shipments will grow from 145 million tons to an estimated 204.6 million tons. We can improve freight transportation while making roads safer and reducing the impact on infrastructure and the environment.


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