14,000-pound trailer's an easy toss for a twister with 100-plus-mph winds
April 5, 2012
How much power does it take to pick up a semitrailer and throw it hundreds of feet through the air? That question must've been on the minds of everyone who watched TV news video shot during the passage of a savage tornado through Dallas last week.
"Winds in excess of 100 mph," answered a National Weather Service meteorologist when a news anchor put the question to him as the storm was still snarling across television screens. The winds spin and move upward at those high speeds; that and the expansive flat shape of van trailers, which were the identified flying objects in this storm, explains how they were grabbed and tossed so forcefully.
"Entertainment Tonight" compared the sight to the special effects in the 1996 movie "Twister." Among the things thrown about in that flick was a tank trailer.
On Tuesday, TV news people in Dallas and elsewhere called the vehicles "tractor-trailers," even though trailers alone were in the images. One commentator was not far off on a weight guestimate, which he put at 6 tons.
Many of the flying trailers were from Schneider National's Dallas terminal, which took a direct hit. A Schneider 53-foot van weighs about 14,000 pounds empty, said Janet Bonkowski, spokesperson at the carrier's headquarters in Green Bay, Wis. A few might have had loads, but the only one she saw had a light load of cargo racks.
"A total of 67 trailers and 36 tractors were damaged in the storm," she said. "Of those, we have no idea which were airborne and which weren't."
One tractor, hitched to a loaded trailer, was occupied by a driver as the twister went by, Bonkowski said. "The driver elected to ride it out in his bunk. The vehicle was picked up, then put down" and the driver was not hurt. Neither were any of the nearly 100 other employees on the premises.
No one at all was killed in the entire area, even though two tornados destroyed more than 600 homes, news reports said.
Schneider issued this statement the following day:
"We are thankful and relieved to report that all Schneider associates who were at our Dallas Operating Center when Tuesday's tornado touched down are safe, accounted for and are back at work today. We are proud of our associates' response to yesterday's tornado: They received alerts of the storm and followed protocol by taking shelter.
"While there was no damage to our buildings at this location, there was extensive damage to our trucks and trailers located in the yard area. Approximately 100 pieces of equipment were damaged in the storm. Recovery efforts began Tuesday night and clean-up is proceeding quickly.
"Our Dallas associates are working hard to restore the facility to working order and to get back to doing what they do best: hauling freight for our customers.
"We are working with customers to transfer and redirect loads and freight impacted by the storm. The storm's impact to freight, our customers and our operations overall appear to be minimal - a remarkable outcome in light of the force of the storm.
"Schneider National is grateful for the support and concern for our associates who work in the Dallas/Fort Worth area. Equipment and products can be replaced; people cannot."
Author: Tom Berg | Posted @ Thursday, April 5, 2012 4:33 PM