Maverick Testing

halltd said:
WOW - I had no idea Patriot used magnetic braking. Those aren't LSMs, but they do look like the brakes on MF. That surprises me because I didn't realize B&M was using brakes like that. Intamin owns the patent on magnetic braking for a roller coaster, right? So, B&M would have to pay Intamin to use that technology? Someone enlighten me please. :)

I believe Silver Bullet was the first US install of a B&M with magnetic brakes. Patriot is second. I am guessing that B&M probably have to pay Intamin if the product uses the same materials, but not the idea. I don't know if they do or don't.

So yes, how do LSMs work in the event of a power failure??? Where's Dave?

Simple answer: They don't.

Since LSM work with rare earth magnets the train would just stop on the hill since there is no current put to the stators (the white fins mounted to the track).

The magnetic braking used after the second launch would not be able to stop a train unless it was not fired at a high speed. They are just trim brakes and there is no way to control them as in how much they slow down the train, Intamin may have a set of proxy sensors detecting speed and be able to drop them out of the way (like MF) in case of a underpowered launch but they can not control the amount of magnetic friction put onto the train.

The brakes on MF are on a pivot controled by an air cylinder. They are set up to be in the up position in case of air (or power) failure to stop any trains coming into the station.

As for a train stoping mid-course there is usually multiple spots on a ride where the track can be removed and the trains pulled off one car at a time and reinstalled onto the track usually at the transfer / storage track.
*** Edited 9/11/2006 2:51:40 AM UTC by David Sagert***

I'm not so sure that LSMs would hold a train in place if there's no current.

Ok I was wrong. After thinking about it wasn't MF the first to use magnetic brakes? Sorry to get off topic but seems fitting with the conversation. I know they don't now after actually reading up on it but becasue the brakes on WT actually shift a bit when the train hit them I always though it was friction. I'm usually not so ignorant on those kind of things but I guess everybody can be once in a while.

MF was the first at CP to use mag brakes but not in the roller coaster industry.

Michael, LSMs are basicallly a series of North South magnets in a line. The mags on the train are also North South mags with the first magnet being oposite of the first one on the lift. As current is passed through the mags on the track they change polarity. By doing this the mags on the train are attracted to the mag in front of it on the track then repelled by it as the current passes through it. This is done in a rapid sequence that is determined by the PLC and either IR sensors or more than likely proxy sensors.

Now if the current stops pulsing through the stators (the mags on the track) then the train would cease to be propelled and actually encounter a magnetic drag as the momentum of the train carries it further up the hill. If there is not enough momentum then it will not clear the hill and it will come to a stop at a point where the mags balance themselves. If the mags on the track or on the train were not strong enough to hold the train stationary on the hill they would not posses the power to propell the train up the hill.

I have done some reading on the subject and I am quite sure this is correct, but I dont have a Phd in electrical motor propulsion so dont call it gospel.

So it sounds like to me they will have to build a back down program for the tunnel launch in case of power loss. If the train is launched, say hits 30mph and then loses power, the train will be halted by rare earth magnets. Since you can't turn these magnets off, you will somehow have to reverse the normal forward flow of the LSMs in order to reverse the train back to a staging possition for a relaunch. Unless the LSM's are retractable, and then in that case, gravity could work as the reverse mechanism.

Second, at the rate the track is going up, I think we'll see a completed circuit well in advance of the December completion steel completion date.

In the event of a power loss, obviously the train would stop being propelled up the hill, and gravity would try and pull the train back down the hill. As the train moves back down the hill, it has to pass over the stators. The magnets on the train moving over the stators will attempt to generate current in the stator wires.

When not in operation, (I think) the stators are a short circuit. Fairly large amounts of current will be generated in the stator as the train's magnets pass over. This current that the train generates will create a magnetic field, just like in normal operation. However, the magnetic field the train generates will oppose the moation of the train, rather than pushing it up the hill. (This is Lenz Law.) Since you can't get something for nothing: (Remember Conservation of Energy in physics class?) the current in the stator is dissipated as heat, and the train is slowed down.

The amount of current that is generated is porpotional to the rate of change of the magnetic field. If the train is moving faster, the magnets are moving faster, and the magnetic filed around the stators will be changing faster. The magnetic field that is generated is porportional to the amount of current. Thus, as the train slows down, less current is generated, and the opposing force to the train is reduced. Thus, magnetic brakes cannot bring the train to a compete stop. Next time Dragster rolls back, watch it. The train never comes to a complete stop, even with the brakes up. Instead it inches its way back to the satation.

I don't know for sure, but I think this is how the stators will be wired, to allow them to act as a brake when not in use. I also believe this is why they didn't use LSMs on Wicked Twister. When not in operation, a LSM can't act as a brake, alowing the train to pass through the station, even when no power is applied.

Dr olds - Back to your first question, a coaster with themeing almost always will do a test before the themeing goes up to make sure the circuit is working as it should, then they will do lots of testing after to make sure clearance is still alright with themeing in place. With Expedition Everest, they had to shave of some of the mountain for clearance, but the coaster was fully tested before the mountain sides went up.

I'm hoping to see testing take place this year. I'm going to make the prediction that they'll run a test circuit by the end of November.

I think with the complexity of this coaster, they will want to get it up and operational as soon as possible. Dragster is probably the only CP coaster that's potentially more complex than this one, but it doesn't have 2+ trains in motion at any one time.

Do we have any inside sources that can let us know when testing takes place?

Steel erection isn't set to be done until December, so I wouldn't hold your breath on testing happening before that. This isn't RCT, after all. ;)

I don't see how steel errection is going to take till December. We're less than a month in from them installing the first piece of track, and it appears they are nearly half done with the circuit layout. (hint: I would love to see another areal photo posted). Am I off here. Now I can see electrical and mechanical install taking some time. But steel errection either appears to be ahead of schedule, or that work over the pond is going to take a significantly long time to complete.

There are still a lot of supports that need to be installed before the remaining track can go up. And a lot of the remaining supports (high, multiple component) are more tricky than what has already been done (low, mostly single piece). And, yes, the pond work will take more time because they will probably have to drain the pond, as it would be pretty difficult to get a cherry picker to extend out sufficiently from the bridge area in FT.

So, yes, they have been tooling along very quickly, but much of what's left is going to be more difficult than what they've done so far.

They still have the swan boat lagoon, which does not get drained until Oct 30th.. and they cant put any supports / track up over there until then... at least it would be hard for them since they would need a JLG over there and the closest place is the bridge... and with reach its a tight squeeze..

Well, there is nothing that says it can't be drained before then. Its not like its a natural thing, its done with pumps. So if they wanted to work on it, they could drain it before then. However, I think for aesthetic reasons, they will wait until the end of the season to drain it and continue the construction there.

magnumdragon200 said:With Expedition Everest, they had to shave of some of the mountain for clearance, but the coaster was fully tested before the mountain sides went up.

That's not an accurate statement. See here: http://rcdb.com/ig2389.htm?picture=19 or here: http://rcdb.com/ig2389.htm?picture=17 or here: http://rcdb.com/ig2389.htm?picture=18

Its obvious that the track isn't complete, yet the mountain enclosure is going up.

I believe he's referring to the actual "skin" of the mountain structure.

I see skin going on there.

halltd said:

That's not an accurate statement. See here: http://rcdb.com/ig2389.htm?picture=19 or here: http://rcdb.com/ig2389.htm?picture=17 or here: http://rcdb.com/ig2389.htm?picture=18

Its obvious that the track isn't complete, yet the mountain enclosure is going up.

I was referring to the skin and most of the outside elements directly around the track openings and flybys were not put up until the ride was complete and tested. I was physically there the day they were sanding off sides of the mountain on the re-entry after the drop. I work at WDW and followed the construction very closely.