well, there's the brakes that stop the car when it's coming back. and those can't be
all magnets, because then if the power goes out, someone gets really hurt. so, i'd assume that if the power goes out and you're on the acceloration part, some sort of pneumatic brake clamps on and stops the train quite fast. if you're up in the air, uh, i guess that they could somehow stop the train (maybe on the uphill) with something not dependent on electricity, and then come up and make you walk down.
what roller coaster did you guys get stuck on at great adventure? when i went last year, nitro was having major computer problems (they fixed that eventually) so the train kept stopping at the top of the hill. then i went opening day this year, and stupidly went on the great american scream machine. new operators and old roller coasters DO NOT mix. it's worse than oil and water. me and my brother get on the train. we go up the hill, down the drop. we make our way to the first brakes (before the heart loop thingy), and those brakes didn't even fire, so we rocketed through there, and that really hurt my back/neck. then, we get to the final brakes (before the station) and the train came to almost an immediate stop. then we sat there for about 15 minutes while they got people who knew what they were doing to fix it. it was kind of interesting though, because the person behind me was trying to squeeze out of her harness, and then a guy came over and yelled at her. then she was like, stuck in it for a while

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