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Air Drag and Fuel Economy.. Really?

Driving back from work, this friday, My friend and I were having an interesting discussion. He suggests driving close to the car (tailgating ) in front and coasting there would improve the Fuel Efficiency because it reduces Air Drag. Spat came my answer: NO. My point was, even in a highway situation, this saving would be less when compared to the fuel expense to catch up with him if there was ever a break in speed (and that going back from work, speeds do break quite often). Not to mention the additional risk of an accident. Although I felt triumphant myself, He didnt bulge in. His example was, the cyclists in a marathon. They keep themselves together to reduce air drag and use lesser energy.

So in the weekend, I do this research. Apparently My friend was very correct on the Cyclists. It is scientifically proven that Cyclists get advantage by moving in groups and there by reducing the drag. Logically (theoritically too) it might sound appropriate to connect the dots to cars. But looks like it is not the case in all cases. If you are driving a car behind a truck, You will be reducing the drag. But practically, Most Trucks drive a standard 55 MPH or around it. Most cars now a days have a very well designed Frontal area to reduce the Coefficient of Drag (CD). At the speeds of the Trucks the cars of today are well designed for drag.

So what about tailgating other CARS. This case is even worse. Traffic situations like driving back from work, or weekend or holiday driving, would generally constitute a lot of heterogeneous traffic and breaking. So tailgating may *not* fetch you what you are looking for. Risk of an accident is much higher than when tailgating a Truck. On the other hand, On Highway, Edmuds gives tips, if you drive with less breaks and no switching lanes, you could achieve as much as 77MPH with better fuel economy otherwise.

In Conclusion, Over all, Coasting is much better than avoiding drag by Tailgating! Either way - Drive safe! And Drive green.

p.s: Did you Know? (My) Camry Hibrid has the best CD in its class!!!

image: treehugger.com
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