New England Patriots quarterback Tom Brady was suspended by the NFL for the first four games of this season for his role in an alleged plot to deflate footballs. (Getty Images)Back to football for a moment, though. Cohn brought out two identical footballs. As he told the story of his investigation, he noted that he bought four off-the-shelf pressure gauges and then pumped each football up to 13 pounds per square inch (psi). NFL rules require footballs to be between 12.5 and 13.5 psi.
He then used the four gauges to check the pressure of the balls. And you know what? Each gauge gave a different value, Cohn related. No consistency at all.
Then, Cohn took the two footballs and placed them outside in 20 deg. Ohio weather for two hours before bringing them back inside and checking the pressures again. Not so surprisingly, of course, the two footballs measured around 11 psi.
Cohn sent his findings to the NFL in a “nice letter,” as he said, adding that they spent millions to reach a conclusion that is fundamentally wrong (and since disproved by most scientists) and “he would have done the testing for $1,000.”
Consider Deflategate debunked.
So what does all this have to do with trucking? Well, the answer is in the gauge, of course.
As Cohn found with the off-the-shelf gauges, no two gauges are the same. That means that a maintenance tech and driver, each checking the same tire for air pressure, will likely come up with two different readings if they use different gauges. How important is that? With a margin of error of +/- 3 psi, that difference could be significant.
For every 10 psi tires are underinflated, a truck will suffer a 1.5% hit to its fuel economy. Underinflation also leads to irregular tire wear and increased likelihood of punctures, Cohn said. With tires losing between 1 and 3 psi each month simply through osmosis, it becomes vital to maintain proper air pressure.