(OT) HeadSmart Lab: Deflategate experiment vindicates Patriots?

Submitted by wildbackdunesman on January 26th, 2015 at 8:39 PM

I know that there has been plenty of talk on this, but I thought this experiment deserved its own thread.


A HeadSmart Lab study using brand new official NFL Footballs...

All footballs are inflated to 12.5 PSI at 75 degrees...like they would be in a locker room...the balls are then put in a 50 degree room and made wet (there was heavy rain in the AFC Title game and about 45 degrees by halftime of the game).

#1 Colder air will condense the air and decrease PSI in a ball
#2 Wet leather will expand and therefore decrease the PSI in a leather football.

Experiment Results:
The footballs lost PSI of up to 1.95 PSI --- perfectly in line with what the Patriot balls were. Keep in mind, only 1 Patriot ball was down 2 PSI. The rest lost less than that.



Edit: I failed to embed and have kids to put to bed so here is the link to a video.



January 27th, 2015 at 6:07 AM ^

There are other experiments now.  All showing the same exact effects on PSI consistent with the Patriots balls.

1) Does colder air lower a ball's PSI?
2) Does wet leather expand, lowering a ball's PSI?

If a cold wet ball has more air pumped into it at halftime and the ball is still cold and wet when measured after the game - why would you think the ball's PSI should change?  The ball at the end of the game would have a very similar temperature as it did at half time and a similar amount of water absorbed into the leather.


January 26th, 2015 at 11:09 PM ^

where did the NFL measure the Patriots balls as being 2 PSI low?  If they measured them at room temp (75 degrees) then clearly something is wrong.  If they measured them at 50 degrees, wet, as done in this study, well then you have the answer.  No one let any air out of the balls.


I just assumed the NFL was measuring the PSI again at room temperature because the only way to measure a PSI drop would be to measure the pressure again at room temperature like when the original readings were taken.   Any PSI drop that was observed at 50 degrees when wet should have mostly gone away once the ball was warmed back up again. 


January 26th, 2015 at 11:39 PM ^

Not just where but when. If the officials let little time pass between bringing the footballs indoors and measuring, then the footballs would still be filled with cool air and would still be wet, which could lead to a lower PSI than when they were inflated.


January 27th, 2015 at 12:28 AM ^

very good point.  Ambient room temperature would be irrelevant if you just brought the balls inside.  It is the temperature of the air INSIDE the balls that is important. 


So I was just assuming the NFL isn't a bunch of idiots and that someone measured the balls again under the same conditions that they were originally measured.  I.E.  after they had been warmed to room temperature.  If they were really measured at 25 degrees lower and wet, well then the NFL is a bunch of idiots and this whole thing has been a non-issue from the start.  Anyone with an automatic tire-pressure reading on their car can tell you what happens when the temperature drops by 25-30 degrees. 


If the NFL let the balls warm back up to 75 degrees and they are still down 2 PSI, well then someone let air out of the balls. 


January 26th, 2015 at 11:26 PM ^

1. The experiment in the video was very simple but telling. I'd like to see full data and also how much time between measurements and how much time between soaking the football and measuring. I also see that they did not take the footballs outside as part of the experiment, so the researchers did not take into account air pressure differences from indoors to outdoors.
2. Where did the Colts inflate their footballs? And where on the sideline did they store them? If the Colts kept the footballs warm and dry on the sideline and the Pats did not, you may have a real explanation.
3. To what PSI did the Colts and Pats each inflate their footballs? Did the Colts inflate their footballs to the higher end of the acceptable threshold and the Pats the lower end?
4. I believe the refs took the footballs back inside to check PSI. However, unless they waited a while before checking, the air inside the ball was still cooler and the ball itself was still wet and therefore expanded, which would yield a lower PSI than when originally inflated.

Whenever the controversy of the week reveals itself, I always choose to wait for facts and data to be released before jumping to conclusions. I often feel alone in doing so because everybody has jumped to a conspiratorial conclusion in this one. I believe if we answer a few questions I laid out above, we've got a good shot at a real plausible answer that does not involve nefarious deeds.


January 27th, 2015 at 5:20 AM ^

 I wouldn't call myself a scientist, although I have a technical degrees if you include engineering as technical, which I do.  You really don't have to go beyond the ideal gas law, and include some evaporative cooling, to figure out the impact temperature has on pressure. I guess if you were in a humid atmosphere when the balls were filled, you would also lose pressure from condensation of water vapor after a 25 degree drop in temperature. That's why people who care about these things use pure nitrogen in tires. 

The OP's piece concisely showed the impact of game conditions.

The only questions now should relate to the particulars of where the balls were tested and did they have a chance to come to equilibrium with ambient temperatures when they were retested. 

Then, of course, there is gauge error, and human error reading the gauge when filling the football, i.e., what angle was the gauge viewed from if it were an analog gauge.

I'm guessing the NFL won't prove a stinking single thing unless they find someone deflating the ball.

As for Mark Brunell and the rest of the talking heads, I wonder how many took college chem or physics (or seasonally adjust their tire pressures).

Mr. Yost

January 27th, 2015 at 7:25 AM ^

If you want it to be a big deal, you can make it a big deal. If you don't want to care, you won't.

Same with Winston. "Findings" are not going to change opinion...at this point, people believe what they want to believe and unless there is cold hard evidence.

i.e. the NFL admitting a mistake and finding that the officials tested the balls incorrectly, or Winston's accuser saying "sorry, I made it all up!"

...and even then some people will be talking conspiracy (the NFL took the dive for the Pats or Winston paid her off with his soon to be NFL money)


January 27th, 2015 at 9:21 AM ^

That's a fair point, but NE lost the benefit of the doubt with spygate.  They don't get to blatantly lie and say "if in doubt we never go close to the line". 

And the I no nothing argument is a joke.  As is the you can't 100% prove we did it.  Its the argument of the guilty.