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ATDynamics projects 200,000 semi-trailers to be equipped with fuel-saving rear-drag aerodynamics technology by end of 2017

The patented TrailerTail design lowers vehicle fuel consumption by reducing low-pressure suction drag directly behind a trailer. Source: ATDynamics. Click to enlarge.

ATDynamics, a supplier of semi-trailer aerodynamics technology, projects that, based on current trucking fleet adoption trends, 200,000 semi-trailers will be equipped with fuel saving TrailerTail technology by the end of 2017. TrailerTail technology, which reduces aerodynamic drag at the back of tractor-trailers and improves vehicle fuel efficiency by approximately 5%, has been incorporated into three of the Department of Energy’s SuperTruck Projects.

ATDynamics launched the patented thermoplastic composite TrailerTail design in 2010. At present, 350 US trucking companies, including top 100 US fleets such as Mesilla Valley Transportation; Prime Inc.; Roehl Transport; and C.R. England operate approximately 20,000 semi-trailers with TrailerTails.

Department of Energy SuperTruck with TrailerTail Technology. Credit: Sarah Gerrity, Energy Department. Click to enlarge.

Each installed TrailerTail offsets approximately the fuel consumption equivalent of removing one passenger vehicle from the road.

The primary reason that the shape of semi-trailers will change is that TrailerTails pay for themselves in 6 to 24 months, depending on the operating profile of the fleet. Investment opportunities that pay 50 to 200 percent annual returns tend to drive action.

—Andrew Smith, CEO and Founder of ATDynamics

Aerodynamic drag accounts for approximately 65% of the fuel consumed by a tractor-trailer. There are four major areas of aerodynamic drag on a tractor-trailer:

  • Front of the tractor (25%)
  • Gap between the tractor and the trailer (25%)
  • Side/underbody of the trailer (25%)
  • Rear of the trailer (25%)

TrailerTail technology maximizes the return on front, gap and side aerodynamics investments by minimizing the vacuum created at the rear of the trailer. The TrailerTail reduces the aerodynamic drag on the rear a trailer by more than 12%—equating to a more than 6.6% fuel-efficiency gain at 65 mph and 9-12% when combined with ATDynamics-Transtex skirts and other minor trailer modifications, the company says.

ATDynamics TrailerTail technology delivers over twice the fuel-efficiency gains of any other commercially available rear drag reduction technology and is the only rear-mounted aerodynamic device which allows fleets to fully comply with 2010 CARB trailer aerodynamics regulations.

The SuperTruck Project is a five-year initiative sponsored by the US Department of Energy to increase the freight efficiency of tractor-trailers by at least 50%. Addressing the low pressure suction drag at the back of tractor-trailers, which acts as a vacuum and significantly reduces fuel economy, is a key part of meeting the project goal.

The US EPA SmartWay program verifies transportation technologies in either a one or five percent fuel savings category. ATDynamics anticipates that the EPA will soon offer guidance on new higher fuel efficiency thresholds to meet President Obama’s orders to reduce the road freight industry’s fuel consumption and carbon emissions. Through combination packages of TrailerTails and trailer skirts, which reduce aerodynamic drag under the vehicle, ATDynamics says it is able to offer trucking fleets immediate 9 to 11% fuel savings.

TrailerTail technology is available from major semi-trailer manufacturers such as Wabash National Corporation.



This technology goes back to NASA work started in 1973.

Roger Pham

...and the oil shocks originated back in 1973. Why was this not done all the way back then, to reduce petroleum dependency?


The real price shock didn't occur until 1979.

One can point to a host of likely reasons, from the fact that composites weren't nearly so advanced and the "aero" tractor with spoiler and fairings wasn't invented (aluminum is much more expensive to shape into compound curves), to the post-1981 slide in oil prices relieving the pressure on the industry.


In 1949, LaBatt's Beer of Canada devised a streamlined tractor trailer that was very energy efficient, considering the heavy steel sheet metal used in most vehicles then. No I don't think the price of oil or the lack of composites has anything to do with the laziness of the trucking industry.


I'm sure it was a pure cost-benefit calculation.  With all the war demand dried up, oil was cheap and plentiful and truck manufacturers were more interested in cranking out quantity than making the aerodynamically cleanest.  If you can make more money with a cheap 6 MPG tractor than a more expensive 9 MPG one, you'll go cheap.

Christopher Miles

Thanks for the NASA link. Nice to know that the Spin-off tech got remembered.

It's amazing looking at those early 70's experiments in Fuel saving tech- Advanced rail and light rail, Personal rapid transit, GE/Chrysler electric cars, etc. Lots of effort(s) to leverage Federal know how to [then] current problems.

Had not known about this NASA effort.

Would be interesting to know if the Vortice(s) research went anywhere.

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