The train may seem like it's flying up to a dead end, but in reality it doesn't have enough energy to make it up the hill. As it reaches the point where normally it would slow and fall backwards, a system of brakes and tires in the tracks slowly Pull it up to the top of the hill, where brakes grab the train. When the track switch is done and changed, the brakes simply let you go, and gravity pulls the train back down into the backwards portion. So remember, even if the brake and pull system failed, you'd just reach about halfway up the hill and roll back. There isn't enough energy for the train to make it up to the top of the dead end sections, which is why you are slowly pushed up to the top.
I'm sure when you get there if you explain to a Cast Member, they might be able to let you sit in the back row farthest from the front, or maybe even go in the control tower and watch it happen if you are very lucky.
:wave: