Hardly new, but worth a mention with fuel prices being what they are, Airtabs vortex generators are said to produce fuel savings in the 4% range. And that means a payback in months, not years. And maybe just a couple of months at that.
As aerodynamic tricks go, these little streamliners are simple — small, triangular pieces of ABS plastic just under 5 in. long and about 3 in. wide tapering to a point, with a sort-of hollowed-out, scoop-like middle. From Aeroserve Technologies of Nepean, Ont., they borrow from aviation technology (even the U.S. National Aeronautics and Space Administration, or NASA, says they work) to create a controlled swirl of air, or vortex, behind a van box or trailer or at the gap between tractor and trailer.
Arrayed in a continuous line up the sides and over the top of a van or a tractor, at the trailing edge, they address the problem of air that has to rush in to fill the vacuum left by the truck. The air has to make a sharp bend around the squared-off back of the vehicle, which creates turbulence and thus drag. Airtabs produce a vortex of air from each side that extends for several feet behind, thus bridging the tractor-to-trailer gap and/or controlling the way air flows into the vacuum at the back of the truck. They work in concert with existing air-management kits.
Airtabs are easy to fit, by the look of things, with three of them per lineal foot, down the sides and across the top at the back of the vehicle.
Among the benefits, according to driver reports, are reduced splash and spray and better visibility to the rear. Others say the Airtabs ‘stabilize’ their vehicles and reduce the flapping of tarps while improving visibility in rain.