Josie Garthwaite

In my latest story for National Geographic Digital Media, I report how trucking companies are looking to boost fuel economy by improving driver behavior, and using on-board technology to monitor and control what goes on behind the wheel.

Just over 33 years ago, 33 truckers competed for three days in a fuel economy contest dubbed the “Double Nickel Challenge.” Named after radio slang for the 55 miles per hour speed limit then in force in the United States, the goal was simple: to test the claim, common among truckers at the time, that big rigs got better mileage at higher speeds.

Long-haul truckers from all over the United States gathered in East Liberty, Ohio, to watch as drivers navigated laps around a track-first at 55 mph, and then at any speed of their choosing. With a few exceptions, they burned less fuel in the first, speed-limited, trial.

More than three decades later, the double-nickel U.S. speed limit-enacted in the wake of the 1973 Arab oil embargo-has faded into history on most highways. But so has credibility for the claim that higher truck speeds beget better fuel economy.

Read the full story here.