American Craft Beer coasters just won’t fly

Physicists from the University of Bonn are taking on the tough questions.

Here’s the deal…

We’ve all seen it happen, bar denizens fueled on beer, attempting to send their round coasters sailing. But they never seem fly like Frisbees do. Instead they tend to flip or spin in reverse, making it nearly impossible to hit your drinking buddy between the eyes.

So why is that? No doubt the world has wondered, but now new research from a team of physicists from the University of Bonn has tackled this critical question in a study published in the European Physics Journal Plus.

And yes, people get paid for this…

Fascinated by the physics that prevent round coasters from achieving the same kind of aerodynamic momentum that make the Frisbee so much fun to throw, lead author Johann Ostmeyer assembled a team to give this recurrent bar activity a more scientific analysis.

Ostmeyer and his research team built a makeshift beer coaster launcher out of two electric motor-powered treadmills to control the horizontal velocity and rate of rotation of each launch.

Then the researchers placed the launcher on a table, and proceeded to launch coasters at various speeds, marking where they landed on the floor. Those coaster trajectories were recorded with high-speed cameras, and “the team used a program called Tracker to extract the coordinates of the beer mat at any point along its trajectory,”according to  Ars Technica.

And they assembled data which proved the flight of a coaster “will invariably break down at about a half second after release” (that’s no fun!), as Smithsonian Magazine noted.

According to this groundbreaking paper, the reason that beer coasters don’t fly like Frisbees is that the only thing they share is that they’re both round. To be fair there are plenty of coasters that are square as well, but only the drunkest among us, try to sail them.

In addition to weight differences, Frisbees have a curved rim which when thrown generate a lift similar to an airplane wing that, at least why their spinning counters normal gravitational pull.

“The wing form of a Frisbee allows it to remain stable for a much longer time when thrown professionally,” the authors write in the study. “The reason is that Frisbees have their aerodynamic center very near to their center of mass and, thus, experience much less torque.”

“Our sincere apologies to everyone hit by a beer mat,” Ostmeyer says in a statement, “be it through inaccurate aim or due to us instigating others.”

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(Banner image credit: Nan Roman)