A new roller coaster is being built in Japan that will go 107 MPH. Rumors have it that the company that built this ride (S&S Power of Utah), has been asked to build one to go 127 MPH. (Take this with a grain of salt, though; it just may be wishful thinking.)
Just how much faster can they go? What would be terminal velocity? How tall would the fastest possible roller coaster be? Currently, Superman: The Escape at Six Flags Magic Mountain goes 100 MPH. The height of the vertical portion is 415 feet, although the cars actually travel only about 300 feet above the horizontal track. Supposedly, at the bottom of the tower, the cars are going at maximum velocity whether they are going up or down and there are no brakes on the vertical portion (except at the peak for obvious reasons). So how tall would a ride have to be to reach 127 MPH? Or 150 MPH? And at what speed would designers have to consider using windshields?
Well, the roller coaster at California adventure achieves considerable speed at ground level. But if you mean for roller coasters that just use potential energy to accelerate the cars, then the equation is v=sqrt(2gd) where v is the velocity, g is the acceleration due to gravity, and d is the vertical distance traveled. So d=(v^2)/(2g). For 127 mph, that’s 164 meters. For 150 mph, it’s 229 meters. Of course, wind drag would depend on the construction of the cars, and can not be factored in without knowledge of such.
It should be borne in mind that most of your ultra-fast rollercoasters don’t have banks or curves. The aforementioned Superman coaster just goes up and then comes back down.
Too many lateral G-forces raises the possibility of people getting hurt just be the sheer force of being whipped around. If you were to build 150mph coasters with the same banks and curves of your garden-variety coaster, you’d have to restrain the guests so tightly, with head restraints and everything, that it’d be too much trouble to bother and not a whole pile of fun for your guests.
I would guess that they will have a new catagory of coasters soon with some sort of magnetic linear propulsion simular to a rail gun. But that’s just a guess.
k2dave, they already do that. Superman: The Escape; Disney’s California Screamin’; and Six Flags’ Mr. Freeze (Texas and St. Louis), Batman and Robin (New Jersey) and Poltergeist (San Antonio); and Paramount’s Outer Limits (Virginia and Ohio) all use magnetic induction motors to propel the trains along horizontal track. But they are expensive and several of these rides did not open on time.