In the infamous "Deflatagate Scandal", Tom Brady, quarterback of the New England Patriots, was accused of deflating his footballs and served a suspension for doing so.
Why is a deflated NFL football advantageous?
For instance, does a deflated football experience greater velocity? Does it travel more accurately?
Letting air out of the ball makes it softer, thus easier to catch. Do note that in the context, it was a rainy season, so there was less friction between the player and the ball, making it harder to catch.
Another would be the point Chris mentioned on pressure.
It's a fair physics question. A deflated ball has less air in it, and hence slightly less mass. Since F=ma, given equal effort (F) by Brady, a deflated ball will experience a greater acceleration, hence will attain a greater velocity, during the throwing motion. Furthermore, a deflated ball will presumably be a bit narrower and hence have different aerodynamics. I'll leave it to aero experts to chime in on this aspect, but less turbulence would likely lead to more consistency, hence accuracy.
That being said, I believe that the advantage Brady was after is indeed related to grip and comfort, and that the effects I describe above are probably negligible.
At lower pressure, the ball deforms more easily, so it's easier to catch.
