Last year, I wrote a post about the physics behind a triple backflip in BMX. Well, as most of you know by now, Josh Sheehan has done a triple backflip on a dirt bike. If you haven’t seen the video, here it is:
Now that he’s done what we had thought would be the impossible (though we said that about the double before Travis did it), that leaves us with the question of whether there is a limit. Buzz Skyline did some calculations at his blog, eXtreme Sports Physics, and came up with a total of four flips.
Image from Buzz Skyline. Click here for more images of his calculations.
Another physics blog, Physics Buzz, took a look at the front flip. While a backflip has the rider utilizing the bike’s natural momentum and the ramp’s angle (which shaves off half of the first rotation), a front flip combats those forces AND the landing is blind. As Jim DeChamp told ESPN, “[I]t’s not a natural beauty trick— it’s like, that is awkward, that is wrong.” The Physics Buzz post looks at both what happens when a front flip is executed properly and when things go wrong.
I’m pretty sure we’re not going to see a triple backflip in the X Games. The ramps just aren’t big enough. Who knows about the double backflip or the front flip, but my guess is that the new Quarterpipe event is going to take riders in the direction of off-axis flips and 360s. We’ll see.