If, after an initial, powered climb, a typical coaster is just that…a coaster. And if the power went off (to the system) during the coasting phase, the very last thing you want to do is to brake it to a stop before the normal end of the ride. What difference does it make if an unpowered, coasting train has no power (due to design) or no power (due to a failure)?
And the coasters I have seen (which is not many), the initial climb is slow, and the ride’s speed comes from the free fall. If the power went off anywhere in the climb, I would expect it to stop instantly, and emergency brakes applied to keep it from starting the fall. So I can’t see how it can get stuck upside down unless being upside down is part of the initial, powered climb, or if something were obstructing the track in an unforseen manner.
The point, as I now understand it, is that there might be multiple cars on the track at once. Or there might be something (like a child) obstructing the track ahead. Or a great gap of track might have fallen off ahead. Or SOMETHING. The point is, the rollercoaster doesn’t “know” what the problem is, so the safest way to handle it is to stop right where you are when anything out of the ordinary happens. So they make the brakes (in the track, not the car, usually) to work whenever the power goes out. By freezing as instantly as possible, the designers have upped their chances that the movement of the car isn’t going to make the situation worse. Unfortunately, in the case of a power outage, it means that they can’t get the brakes to turn off even when they determine it’s safe to do so.
If we were talking about a tradition roller coaster that’d be valid, but this isn’t that kind. A traditional coaster is lifted to the top of the lift (initial) hill by a chain mechanism. If the power goes out, or the train snaps, the train simply stops on the lift hill – not from emergency brakes (non-existant on lift hills) but due to the anti-rollback device. That safety device is what makes the familiar “click-click-click” sound as rollercoaster goes up the lift hill, and I drew the diagram over at Wikipedia to illustrate it: Lift hill - Wikipedia
That said, this appears to be a special kind of rollercoaster where the lift hill (or launch hill if this is indeed launched) is vertical and then at the very top turns upside down. If the power goes out, it’s going to do the exact same thing as any other roller coaster whose power goes out when a train is ascending the lift hill, stop right where it is. That’s the safest thing to do. So to answer your question, yes, I think the upside down part is part of the initial powered climb.
Now, rollbacks on launched rollercoasters are a different story. They’re perfectly safe and the rides are designed to allow them, but for the unknowing aboard, I can imagine it’s pretty scary:
Look at a modern coaster. There are multiple cars on the track at the same time. If you don’t brake them in place when power is lost and you just let them coast, you are going to get a rear end collision somewhere, probably at the station. This wold be, not good.
Also what happens if a car suffers a failure and stops on the tracks? You have to be able to prevent the other cars from hitting it.
Maybe I don’t understand “modern” coasters, but even if you have multiple cars or trains operating simultaneously on the same track, if they are all unpowered during normal coasting operation, I don’t see why you would care what the power does. How is it affecting the coasting units? It won’t launch any more trains, that’s for sure. Do any modern units re-power the trains in mid-ride?
Modern coasters that run more than 1 train have their tracks split into virtual sections called “blocks.” Computer systems monitor the positions of the trains with sensors and only allow one train in each block at a time. Now, in general roller coasters do NOT have the ability to stop the train anywhere, so each block has a section of track that has the ability to stop the train and start it again. For example, the lift hill is often considered one block and can stop the train simply by stopping the chain, and restart the movement again once the block ahead of the train is clear by starting the chain again. Blocking simply allows the system to safely run multiple trains on the same course without the potential for them crashing into one another should one train get stuck or stop, power failure, etc.
Other blocks have what’s called, “block brakes,” which are short, flat pieces of track about the length of a train with brake runs that can stop the train should the block ahead of that block remain occupied. When (and if) the block ahead is initially blocked and the system stops the train in that block brake. If the block ahead becomes clear again, the block brake releases its brake and allows the train to continue either with drive tires or by the block brake itself being slightly inclined down to let gravity take over.
In the case of a power failure, all blocks default to the braking system and every train that’s not currently in a block will continue around the course until they hit the next block brake and they will stop, quite abruptly.
If I didn’t explain blocking decently you can check out this section on Wikipedia, along with the other articles I linked to in my post… Although I wrote most of them so they still might be clear, so if you have any other questions just ask.
