A U.S. engineer says he is trying to develop methods of reducing vehicle drag so as to improve the gas mileage of planes, automobiles and trucks.

Washington University in St. Louis Professor Ramesh Agarwal said a reduction in drag means less fuel would be required to overcome the resistance encountered by a moving vehicle.

Agarwal and his students have successfully demonstrated the drag of airplane wings and cars-trucks can be reduced by employing active flow control technology, in which actuators are placed on the surface of the vehicles to modify the air flow to reduce overall resistance.

"The most promising actuators are the so-called synthetic jet or oscillatory jet actuators which are embedded in the surface of the body (such as an airplane wing) and essentially perform injection and suction of the fluid from the surface in a periodic manner," said Agarwal. He has demonstrated the transonic drag of an airplane wing can be reduced by as much as 15 percent and his students applied the concept to cars and trucks and achieved up to an 18 percent reduction in drag.

Although the technology has not yet been deployed on any commercially available vehicle, Agarwal said it is being investigated by airplane and automobile companies worldwide.