They have a 'sliding transfer table', in which one is being loaded/unloaded, and the other trian in launched. When it returns, train, track and all slide to the right or left, and the other is launched. Only when the 'othe' train returns from the circuit, then the table slides the other train into place. It is pretty neat to see, and it is a better ride the B&R Chiller. "Speed" in Vegas is good, just 35 seconds of shortness. That ride only has one train.