Changes to the stopping distance regulations are looming – but manufacturers say they’ll easily clear the bar
With the National Highway Traffic Safety Administration’s new stopping distance regulations for heavy trucks becoming law Aug. 1, you’d think the trucking industry at large – and heavy-duty truck brake manufacturers in particular – would be hustling to meet the new guidelines. But the opposite seems to be the case. A mood of quiet confidence – particularly on the part of brake component makers – seems to be prevailing.
“We’ve actually been working on this regulation for quite a while,” says Gary Ganaway, director of Bendix Spicer Foundation Brake’s Drum Brake Engineering Group and marketing. “We’ve been working closely with our OEM customers so that we can now stress that the impact for a fleet from a spec’ing standpoint should really be minimal on these new regulations – no retrofitting will be required.” That’s because after Aug. 1, the only vehicles that fleets and end-users will be able to purchase will be those that meet the new requirements. “We believe this will be a seamless transition for fleets,” Ganaway says.
For the customers – the fleets – that same sentiment also seems to hold true. “This is going to be relatively painless, particularly when you compare it to all the emissions regulations we just worked through,” says Carl Tapp, director of maintenance for Tontitown, Ark.-based P.A.M. Transport, who believes the overall regulations will be a good thing safetywise.
“You see it happen every day – somebody in a car takes a chance by cutting in front of a truck because the motoring public doesn’t realize how hard it is to slow or stop a big rig once it’s up to speed,” Tapp says. “So anything you can do to advance and promote safety in the industry is a good thing in my book.”
The limits of physics
Under the new rules, Phase I of the stopping distance regulations will require three-axle tractors with a gross vehicle weight rating (GVWR) of 59,600 pounds or less to meet the reduced stopping distance requirements by Aug. 1. Phase II will require all two-axle tractors and three-axle tractors with a GVWR above 59,600 pounds to meet the requirements by Aug. 1, 2013. Voluntary early compliance is permitted.
For a small number of heavy severe-service tractors, the stopping distance requirement will be 310 feet under the same conditions. In addition, the final rule requires that all heavy truck tractors must stop within 235 feet when loaded to their lightly loaded vehicle weight (LLVW).
At first glance, the stopping distance regulations seem daunting. Passenger cars in the United States traveling at 60 mph must be able to come to a full and complete stop within 140 feet. Class 8 tractors currently must come to a full stop from the same speed in 355 feet. After Aug. 1, that distance will be cut 30 percent to 250 feet for new vehicles.
The purpose of these regulations is to reduce the number of fatalities and injuries associated with crashes involving tractor-trailer combinations and other vehicles. Once all heavy-truck tractors affected by the rules are equipped with enhanced braking systems, it is estimated that about 227 lives will be saved annually, while 300 serious injuries will be prevented. The final rule also is expected to prevent more than $169 million in property damage annually through averting or lessening the severity of crashes involving Class 8 vehicles.
And while brake manufacturers and OEMs say they will meet these new regulations with relative ease, some experts believe the new regulations are quite aggressive from an engineering standpoint.
“I think we’re approaching the limits – or rather the limits of physics – for stopping vehicles this heavy on our highways today,” says Tom Runelf, engineering manager for Bendix Spicer Foundation Brake’s Drum Brake Engineering Group. “But we have some advantages today that we haven’t had in past decades.”
