TTD Incidents & E-Stops

To the TTD Crew:

How does a TTD E-Stop work? Can you stop it at any point on the run or only during launch or on the break run? Can you even stop it during launch or would that blow the LIM? How can you stop a coaster at 120 MPH quickly & safely?

Any amusing incidents on TTD? (Other than when it got stuck/balanced at the top.) I'm sure a lot of bugs have been eaten. Any Fabio-like bird strikes? Pukers, etc...

Thanks for the info.
*** Edited 2/15/2007 3:09:46 PM UTC by Emiroo***

You can only stop it where there are brakes.

There are no LIMS on TTD.

If on launch and the E-Stop is hit, I believe the engine immediately shuts-down/disengages and the brakes pop up, they'll stop the train as quickly as possible.

If you're past the launch, you have to wait for it to come back down, either into the launch run or into the brake run.

Once you hit the launch buttons, that's when the train hooks into the catch car and moves back a couple feet. If you the trains are moving from the station into the launch position, you can hit automatic stop and that will stop the kicker wheels. Once the launch buttons have been pressed it's ready to go and the only way to stop it is through the E-stop. Once it starts launching, you can't really stop it. If you hit the E-stop then the system will shut down, so the train will run off its own momentum. So depending on where you are exactly on the track, you may or may not get a rollback. The brakes will still pop up behind the train as it passes it like normal, and once it loses its momentum, the ride needs to be turned back on before it can be moved back to launch.

Someone please correct me if I'm wrong, but I'm pretty sure that's how it works.

If you press the estop fast enough, you'll get something like the short shot in this video at around 1:30.

The later in the launch that extop is pressed the farther it will go. If pressed fast enough, the train will stop somewhere on the launch. If pressed after but while the train is over enough brakes, the train will go to the hill and roll back. If pressed late enough in the launch, the train will make it over.

While the estop in the video was caused by a hydraulic estop, pressing the estop button shuts down the launch system and pops the brakes up simultaneously in the same manner.

*** Edited 2/15/2007 6:18:30 PM UTC by Jump to Conclusions***

Not to be "Mr. Knowledge" and tear someone else up, but why do people ALWAYS think that TTD has LIM's on it? I guess they think the brakes are LIM's? I don't know, I guess I just take more notice in how things work, but I never really saw how these look alike....

If i'm not mistaken, wasn't an E-stop responsible for KK's accident last year where it tore up some magnetic brakes?

Not quite. A bolt failure caused the liner inside the trough that the launch cable travels through to come loose and create friction against the cable. The friction caused the train to not accelerate to the correct speed. The rubbing of the cable against the inside of the metal trough caused sparks and shards of metal to fly out from the bottom of the train. The engine, as it is designed, attempted to compensate by applying more force to the cable to attain the 128 mph.

The brake fins go up on a timing pattern, independent of the launching mechanism. There are four braking zones, and each zone has about 24 individual brake fins. The fins actually caught up to the launching train as the timing pattern of the rising fins was faster than the accelerating train. The magnetic brakes began to slow the train in the launch area, and the engine tried to compensate even more, and dragged the train through the brake zones. The catch car released, but the train was still in the brake zone and came to a complete stop at the bottom of the hill.

This occurred during a routine morning test run. Damage occurred to the launch cable (frayed and needed to be replaced), engine (minor routine damage to seals), and brake fins (many needed to be replaced). The brake fins in the launch section are mounted in such a way to keep fast moving trains from moving backwards into the station, but a fast moving train being pulled forwards caused an unexpected stress on a number of fins that bent them forward. Not all of the fins need to be replaced, but there were more damaged fins than Six Flags had replacements, and had to be specially ordered from Intamin.

^And that's one of the only explanation I heard about the incident and by far the most detailed.

I takes a Cedar Point fan site forum to get the real answer about a Six Flags ride. :)

That's actually from wikipedia.:)

Wikipedia is a fine resource.

TTD 120mph said:
The brake fins in the launch section are mounted in such a way to keep fast moving trains from moving backwards into the station, but a fast moving train being pulled forwards caused an unexpected stress on a number of fins that bent them forward.

This is where all the explinations I've heard fall short. The copper alloy plates are mounted to withstand bidirectional force. The reason is that they are symmetrical in design and therefore can handle the same force in both directions. Something else must have happened.

Oh yeah, Wikipedia "The free encyclopedia that anyone can edit."

What happened to the explanation of: The trough liner was loose, the catchcar caught an edge in the liner and basically stripped the liner up out of the trough and therefore damaging lots of stuff.

^Gremlins, someone fed them after midnight again.

I waited 2 minutes once last season during the week in May when my physics class went. But it was for the middle of the train, The front took me about id say no more than 8 minutes... by the end of the day though the line was about 10 minutes for a normal spot

^ - what does that have to do with E-stops?

I think that was supposed to be in the other thread about getting a walk on..

JuggaLotus said:
What happened to the explanation of: The trough liner was loose, the catchcar caught an edge in the liner and basically stripped the liner up out of the trough and therefore damaging lots of stuff.

Because that's no fun! :)

Jump to Conclusions said:
This is where all the explinations I've heard fall short. The copper alloy plates are mounted to withstand bidirectional force. The reason is that they are symmetrical in design and therefore can handle the same force in both directions. Something else must have happened.

I too was kind of confused when I first read that. I mean it doesnt really make sense to have it only work in one direction. So then, like you said, the explination as to why the brake fins were bent forward has to be something else.

^ Possibly the break fins are only able to withstand so much force and the train was moving too fast that it forced them forward. Just a thought. *** Edited 2/16/2007 2:35:42 PM UTC by CoasterChris***

The brake fins are likely over-engineered by too large a margin to be damaged as a result of the train going "too" fast.

I like how you not only notice my thought, but also how you took the time to realize my spelling. lol