Accident on SFNE S:ROS and impact on MF/CP

just a mere thing but not too long ago the trains at cedar point on the maintanance force collided even though it wasn't that hard the brakes/whatever did fail and i believe it was the yellow train hit the red one early one morning during a test run.

RideMan, I agree that you can't just put 50% more brakes on the ride (well at least magnetic).  However, I think this number can also be manipulated to mean that the current braking system needs to be able to slow the train sufficiently to the point of having control over the train as it approaches the waiting point even if 50% of the current braking fails in some way.  Perhaps the solution is speed monitoring and backup mechanical brakes, or perhaps that margin is built into the ride already.  There are even some rides out there that insist on a least 1 closed mechanical brake between trains at all times.  Something to think about.

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-Brian
I really should be working...

I didn't think that the brakes failed...I thought the kicker wheels didn't grab or something...

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MF count: 20

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Wolfhounde said:
"RideMan, I agree that you can't just put 50% more brakes on the ride (well at least magnetic).  However, I think this number can also be manipulated to mean that the current braking system needs to be able to slow the train sufficiently to the point of having control over the train as it approaches the waiting point even if 50% of the current braking fails in some way.  Perhaps the solution is speed monitoring and backup mechanical brakes, or perhaps that margin is built into the ride already.  There are even some rides out there that insist on a least 1 closed mechanical brake between trains at all times.  Something to think about.

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That certainly makes sense. Personally, I like the approach used on Millennium Force, where fixed trim brakes are used to bleed off some speed before the train comes into the controlled braking area. You can't guarantee that a magnetic brake won't fail, but the magnetic calipers are certainly the most reliable element in a magnetic braking system...it's the one part that won't wear out and won't fail catastrophically without giving you some warning...the biggest danger would be the catastrophic failure of the brake fin or the caliper mounting bracket, and either way, there are some failures which are so unlikely that it is really impractical to design for a failsafe condition.

If it turns out that the Superman brakes failed, though, I think what we will find is that it was some kind of controls failure...that the brakes were open because the computer told them to open. In that case, it is a problem with the ride controls because it doesn't matter whether you have five calipers or fifty, if your control system tells the brakes to open, they're gonna be open and not there when the train comes in. We tend to think in terms of mechanical failures, but it could very well be that there is no mechanical failure at all, but a programmed logic error with mechanical consequences. There is a name for that condition, but it isn't broadcastable. :)

The one way to prepare for such an incident isn't to include more braking power, but rather to include an extra block on the ride, and keep an empty block between trains. It's hyperconservative, and it results in much longer station headway, but it does add another layer of security against failure. But then again, if the controls fail, even that isn't guaranteed to prevent an incident...

--Dave Althoff, Jr.

I always thought that control systems had PLD's in them so hardwired logic would override a software failure. Maybe not though.
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DIPPIN DOTS!!!111 THEY ROXOR YUR WORLD!!1!

*** This post was edited by Jmstuckman on 8/17/2001. ***

Yeah, i think MF is Pretty safe...  but it is something to imagine what would happen if all the brakes on MF failed...  trains colliding at 65 mph.... ouch... splatterific... not worried though.