In the event of a rollback...

How does the train and sled not hit each other? Doesn't the sled start its return to the launch position immediately following the launch?

That's a good question, but I haven't heard a good answer. The sled being in the way is the common theory about why the sixth train had to be sent back to Europe for repair (that's pure rumour and speculation, so take it for what it's worth).

If you look closely at the last several sections of track, you'll see that there's an inner row of those air pistons. I assume that these lower the launch sled track so it essentially is out of the way in the case of a rollback.

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Jeff
Webmaster/GTTP - Sillynonsense.com
"Pray that your country undergoes recovery!" - KMFDM

This is probably also why it can't reverse and come back to the station at a high speed right away. It needs to be in that lower section to be out of the way of a train that rolls back.

-Matt
2001 Magnum Crew
2003 Magnum Crew

I've watched it launch a number of times and I think Jeff is correct. I'm pretty sure they lower the sled's track at the end of the launch track. There may also be magnetic brakes for the sled, but it's hard to tell.

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Florida may have Disney World and Key West,
but Ohio has Cedar Point and Put-In-Bay.
It's great to live in Ohio!

Does anyone know if it has rolled back yet?
*** This post was edited by Allen 5/20/2003 4:53:57 PM ***

I have answers for you!!

With the train in the pre-launch position, you can get a look underneath, so the key is in knowing where to look...

Just ahead of the fourth axle of the train, the third car has a slot in the bottom of the center beam. On either side of the center beam there is a small canister. At the bottom of the canister is an electrical contact.

When the train is brought into the launch position, the canisters rest on a pair of electrical contacts on either side of the launch sled channel. The launch sled is brought back to the launch position if it isn't there already, and you will then hear a 'clunk'. Next, the advancing wheels under the back of the train are lowered, and the train rolls backwards a couple of feet.

Of course, at this point there is no way to see what is going on because there are brake fins in the way. My theory is that the launch dog on the bottom of the train, actuated by a solenoid, drops out of the aforementioned slot and into the slot on the launch sled. The train rolls backward until that dog engages with the back of the sled, pinning it in place. Once the train gets past the launch position, there is no longer any power to hold the launch dog down, but the launch sled holds it in place until the end of the launch track.

At the end of the launch, the launch sled hits a set of magnetic brake fins and comes to a sudden stop. The train continues, and as it overruns the launch sled, the launch dog retracts...either spring loaded or counterweighted. So if the train comes back, the launch dog will be retracted, and will not engage with the launch sled. That way, the sled can be 'in the way' and well on its way back to the launch point; there is no need for the launch sled to wait for the train to clear the tower before resetting. In fact, it is absolutely necessary for the launch sled to return almost immediately after launch, before the train climbs the tower, if it is to reset in time to make the next design launch interval.

I hope that makes sense! I am hoping to make some updates soon to the feature over on Virtual Midway now that I have some photos available, and now that I have seen the thing operate...

--Dave Althoff, Jr.

Did anyone else get a headache from reading that?

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'03 Magnum Crew * magnum count: 2275 * '03 count: 42 * www.dannyjphoto.com

I did.

So, Mr. Rideman, are you saying that there's a (for lack of an easier term) pin on the launch sled that raises up and down to engage the train? As I gather, you're saying that that pin drops down after the train clears the launch, enabling the train to coast backward over the sled, without making contact with anything, in the event of a rollback.

Would that be a simple way of saying what you just said?

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- John

please say it is, cuz i didnt understand anything he just wrote!

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"it's like eating in the kitchen of a delightful italian stereotype!"
Trips to Cedar Point: 2
Dragster: 3 Millennium Force: 41
Raptor: 30 Wicked Twister: 13

It's never simple with Dave. :)

I wouldn't be surprised if he was right, but that sounds like too much complexity and not elegant enough for Intamin's standards (yeah, I know I'm talking about a company that designed a ride with more switches on it than the rest of the park's rides combined).

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Jeff
Webmaster/GTTP - Sillynonsense.com
"Pray that your country undergoes recovery!" - KMFDM

The system Dave described is practically the same as what Schwarzkopf used on the shuttle loops. The big difference being that the TTD train is pulled by it's "chain dog" rather than pushed from a retractable plate on the rear of the train like on a shuttle loop.

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Scott W. Short
mailto:scott@midwestcoastercentral.com
http://www.midwestcoastercentral.com

That made perfect sense to me. Too much complexity? We are talking about swiss engineering you know.

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cyberdman

Allen said:
Does anyone know if it has rolled back yet?

Yes. . .a number of times. Both with and without guests in the trains.

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Ross: Do you have a minute? I’d like to talk to you about something I’m, I’m really uncomfortable talking about.

Joey: Sure. What? About uh, you showering with your mom?

Ross: I actually had a topic in mind!

I saw a rollback this morning.. with nobody on the train.. it was reset in about 10 minutes... the train rolls back down and stops just ahead of the bleachers.. it was cool to see.. then the break fins kept lowering and rising about 6 times as they rewound the train back to the launch slowly... it was a crowd pleaser for everyone there.. it felt like a stadium of applause...

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TTD=5. MF=77. Raptor 100+ Magnum. 250+ lost count.

Michael Darling said:
So, Mr. Rideman, are you saying that there's a (for lack of an easier term) pin on the launch sled that raises up and down to engage the train? As I gather, you're saying that that pin drops down after the train clears the launch, enabling the train to coast backward over the sled, without making contact with anything, in the event of a rollback.

No, the pin is on the bottom of the train. Just before the launch, the pin drops down into the slot on the launch sled, and the back of the launch sled holds it in place. At the end of the launch, the pin swings up out of the way.

You have the right idea, but with the pin on the wrong component and moving in the wrong direction. The result is the same, though...in a rollback, the pin should be well clear of the launch sled. As Scott noted, it's almost exactly the same as on the Schwarzkopf shuttle loops, except that the pin is ahead of the 4th axle (center of train) instead of behind the last car.

--Dave Althoff, Jr.