
A transportation researcher says he’s exposed the truth of a misleading truck productivity report released earlier this year which warned about the dangers of longer, heavier trucks in the US.
Daniel Blower, an associate research scientist at the University of Michigan Transportation Research Institute and expert on truck safety and truck crash data said the productivity study – conducted by the Multimodal Transportation & Infrastructure Consortium on behalf of the Railway Supply Institute – is biased and severely flawed.
Some of the problems include trucks being misclassified, crash statistics and fatalities being miscounted, techniques that result in double-counting, incorrect crash statistics and unexplained estimates, among other problems.
“The errors are substantial and not recoverable,” he said. “In the process of trying to understand how the authors could have gotten the numbers so wrong, I found fundamental errors of analysis and evaluation.”
Blower’s critique, done at the request of the American Trucking Associations, basically debunks the MTIC report’s conclusions that increased truck sizes and weights in the U.S. bring “risks and detrimental impacts” to public safety.
“In the end, I found errors and misconceptions serious enough to undermine any validity to the crash rate analysis,” Blower said.
That MTIC study claimed a 15.5% higher fatal crash rate involving double trailer trucks compared to single trailer trucks, and a more than eight times higher fatal crash rate for trucks with six or more axles as compared to those with five axles.
The claims were repeated unchallenged by many media outlets at the time.
Real world experience in Canada, where some jurisdictions allow double 53-ft trailers, shows that long combination vehicles in fact have a much higher safety compliance rate and lower crash risk than conventional tractor-trailer units.
“Dr. Blower’s analysis demonstrates what we have been saying for a long time,” ATA president and CEO Bill Graves said. “Trucking’s critics have no qualms about stretching, sometimes well past the breaking point, data and arguments to smear our industry.”
Graves said evidence shows that more productive trucks, like twin 33-foot trailers, improve efficiency while not creating the safety problems special interest groups claim they will.
“In the case of this most recent report, so far as to stretch the facts beyond recognition and well past the point of being useful in constructive discussions about safety.”