The science of the tandem draft

Sir Isaac Newton died 220 years before Bill France sat down with a group of race car owners at the Streamline Hotel and founded NASCAR in 1948. But Newton's laws of motion -- three physical laws that describe the relationship between the forces acting on an object and its motion due to those forces -- are behind almost every decision made when engineers look for mechanical competitive advantages in today's NASCAR.

To explain what's happening to a Cup car at high rates of speed, particularly with the recent phenomenon of two-car bump drafting, I turned to three NASCAR engineers to help explain the physics behind the performance.

-- Steve Hallam is executive vice president of competition for Michael Waltrip Racing. A graduate of Loughborough University in England, Hallam previously worked in Formula 1, first as the track engineer for Team Lotus and then heading up McLaren's F1 efforts. After three decades and six world championships in open-wheel racing, Hallam moved to NASCAR in 2009 as director of race engineering for MWR.

-- Travis Geisler is competition director for Penske Racing. A former go kart racer who earned his degree in mechanical engineering from Vanderbilt University, Geisler drove in both the ARCA Series and the Nationwide Series. He joined Robert Yates Racing as a race engineer, and has worked as team engineer and crew chief at Penske.

-- Steve Hoegler is team engineer for Clint Bowyer's No. 33 Chevrolet as part of Richard Childress Racing, A native of Cleveland, Hoegler earned his mechanical engineering degree from Ohio University. After working for Petty Enterprises and Hall of Fame Racing, Hoegler joined RCR three seasons ago and works hand-in-hand with crew chief Shane Wilson.

"Everything can be traced back to Newton's three laws of motion, which basically define how we operate today," Hallam said. "You can reduce pretty well everything back to force equals mass times acceleration."

And it's especially true when engineers try to determine the physics behind the push drafting now prevalent at superspeedways such as Daytona and Talladega. It's all about fluid dynamics: moving air out of the way in an effort to get through it as cleanly as possible, while keeping enough air around to provide sufficient thrust while cooling the engine.