How does Top Thrill Dragster work? Basically, it's a giant fishing pole that pulls the train in super fast. Cedar Point contacted Intamin to manufacture the ride who chose to go with a hydraulic launch based on their speed, acceleration, and power requirements. There are 32 hydraulic motors, 16 on each side connected to an internal ring gear. The power from all of the motors is transferred to the giant cable drum by a planetary gear box. The cable connects to a sled that rides in a track within the coaster's launch track. It attached to the underside of the train and pulls it toward the 420 foot hill at 120 mph.
There are two sensors on top of the 420 foot hill. The distance between the two sensors is known so they can take that value and divide it by the time it takes the train to get from one to the other. This gives the computer the train's speed going over the top of the hill. The computer takes the average speed of the three previous trains in order to determine the power to give to the hydraulic motor. This presents a problem if the first three trains are filled with swimsuit models and the fourth train is carrying football players. The power is not going to be enough to get it over the hill. One thing I am not sure about is how they handle empty trains, or going from three empties to one full. I think maybe they can compare that average to historical data?
Why does Top Thrill Dragster break down so much? You have to remember that it's a very complicated piece of machinery. The ride is covered in sensors. Every single brake fin has two sensors to detect alignment. The cars have copper fins attached to the underside of their chassis and must line up exactly with the fins mounted to the tracks, if they were to be off there could be a huge accident, hence all of the alignment sensors. There are two huge brake runs, the fixed one after the hill and the pneumatically controlled brakes on the launch track. They come in rows of two. That's a lot of brake fins! If just one of those sensors fails or is faulty, the entire ride is shut down.
How to design a roller coaster.