As this very popular video was making the rounds on social media, the average comment was something like this:
WHAT!? That amusement park ride is CRAZY! I would never ride on that.
Don’t worry. The video is fake. It’s a clever fake, but it is indeed fake. Yes, there is a real ride called the Gyro Drop, but it doesn’t do that crazy stuff. But just because a ride is fake doesn’t mean we can’t analyze it. So, what would it feel like riding on this fake ride?
I’m going to start with a video analysis to get the position vs. time data for the humans on this ride (I guess they would be fake humans too). The idea is to look at the location of an object in each frame of the video—it can be sort of tedious, but I use this awesome (and free) software Tracker Video Analysis. Oh, I need to know the size of something in the video. It appears that the real Gyro Drop is 70 meters tall. That will at least give me a rough approximation for my analysis.
There are three parts of this crazy ride that I want to look at. The first part has the seats all moving up the tower, and then individuals drop down on a wire. Here is the motion of just one of these humans during this part of the ride.
It’s actually weird (and of course fake) that as soon as the humans are released from the platform, they start moving down. If the platform was moving up (it was with a speed of about 11 meters per second), then the humans should still be moving up as they “fall.” Anyway, I measured the acceleration with a curve fit anyway. This puts that part of the motion with a downward acceleration of about 47 meters per second squared. Just for comparison, the acceleration of a dropped object would be 9.8 m/s2. That means there would need to be some type of rocket pushing these humans down.
Wait! On the way down, the humans travel at a speed of about 18 m/s. Then at the end of the line, they get pulled back up with a speed of 16 m/s (about the same as down). This change in speed (from down to up) happens over a time interval of about 0.2 seconds or less. That would put the stopping acceleration at 170 m/s2 or about 17.3 g’s. Note: fighter jets pull about 9 g’s for very short periods of time.
OK, now for the next part of your wonderful ride. The humans are spun around in a circle. The angle of the cables from the vertical axis is about 50 degrees (but they aren’t all the same) with a cable length of about 19 meters (again, they aren’t all the same). By looking at the video, it takes about 4 seconds to make a complete round trip.
Since these riders (or captive riders that can’t escape now) are moving in a circular path, they are accelerating. The magnitude of the acceleration depends on both the circular radius and the rotational speed. Based on the values above, the one dude I measured would have a circular acceleration of 35.9 meters per second squared or about 3.7 g’s. I don’t have actual values, but I have a feeling that this would be the highest acceleration for a swinging-turning ride IN THE WORLD.
However, just from this circular swing thingy, you can tell the ride is fake. It turns out that for a ball (or human) swinging in a horizontal circle, there is a relationship between the rotation rate, the length of the cable, and the angle the cable makes. You can read all the physics details in this older post—it even includes a gif. So if I use the length of 19 meters with an angle of 50 degrees, it should take the human 7.6 seconds to make one complete trip—not just 4 seconds. BOOM. It’s fake.
Now for one last analysis. At the end of the ride, all the people are pulled back up to the moveable ring on the tower. This ring then accelerates downward (in a similar fashion to the real GyroDrop). Here is a plot of the position of this ring as a function of time from the video analysis.
That’s actually much smoother than I expected. But you can see that by fitting a parabola to this data, this parabolic fit is the same as the following kinematic equation (for the motion of an object with constant acceleration).
The term in front of the t2 for the fit would have to be 1/2 the acceleration. That puts the acceleration at the beginning of this drop at 74 m/s^2—that’s even greater than the downward acceleration at the start of the fun ride. Gravity alone won’t cause this kind of acceleration. There would have to be an external force pushing down on the moveable ring. But that also means there would be a downward pushing force on each of the riders—a force equivalent to more than 6 times their weight. I don’t think this would make them very happy.
Oh, what about the stopping at the end of the ring drop? This has an acceleration that is a little bit lower. Only 6 g’s. Everyone should be happy that it’s not as bad as the acceleration from the first part. Oh, maybe they already passed out—or worse. Good thing the ride is fake.