Giant Drop System?

[Cove26flags]

How does the giant drop ride work?

[FParker185]

(you better believe this will be detailed)

Car goes up, car comes down, repeat

If that satisfyed you, congratulations! I now pronounce you easily impressed.

In reality, there are 6 tracks, each an independant system (though SFGAM happens to run them as one ride), each track has a large motor at the top of the tower in the cap that powers the catch wagon. Each track (from now on I('ll just talk about one track since they all operate identically) has a catch car that can travel up and down the tower by means of a wire that is connected to the top of it, the wire goes up around a winch at the top of the tower and back down the inside of the tower and is attached to a counterweight which is approx of equal weight of the catch car. (I'll start now at the beginning of the mechanical cycle), catch car is at the top of the tower, the winch runs in reverse to lower the catch car til it comes close to the actual ride vehicle at which point it slows down and slower attaches to the vehicle by means of an L shaped "hook" latching onto a U bar with a bearing on top, at this point the ride will wait for operator input to start the second half of the cycle, when it gets the command the winch starts in normal mode at around 1/3 speed lifting the car as the brakes (more on that later) are always engauged once the car is lifted clear of the brakes and it speeds up to full speed til it gets near the top of the tower at which point it slows for the final 10 feet to the top, when the car makes it to the top the cable brake engauges (click you hear when the car stops moving upwards), after a 3 second delay there is a device at the top of the tower that pulls back the hook dropping the car (no cables attached) into total freefall for around 120 feet until the car hits the brakes and it is slowed til it lands on 2 hydraulic buffers and electricity is applied to open the valve to release the restraints and that ends the Mechanical cycle, now for brakes.....


Brakes are extremely simple, though there is a thing or 2 that needs to be known about the physics of what's happening...

1. all electrical current produces a magnetic field.
2. moving a non iron bearing conductor through a magnetic field produces electric current in the conductor.

lets see, that's 2, we can continue

(que sequence of the car beginning it's freefall)

Car is in freefall, there are 2 sets of extremely strong magnets on the back of each car (Rare Earth Magnets, they are naturally magnitized by the earth over millions of years and can never loose the magnetisim), anyways as the car nears the bottom of the tower there are 2 rows of Copper fins attached to the tower that stars around 60 feet up the tower. (I've now successfully lost myself and dont want to retype this over so)......

The car falls til the the fins on the tower start passing through the magnets on the back of the car, the movement of the car(and there for the magnetic field) over the fins produces an electric current in the Fin, which as we learned earlier will create it's own magnetic field of the same polarity, and as we all learned at a very young age like magnets repel (north/north, south/south), and that action is what slows the car, though here is the hitch with magnetic braking.... As the car slows the movement of the magnetic field slows and as a result less current is generated in the fins, and that ends up with less braking force and there is a point where no more braking force can be generated, rendering Magnetic brakes physically impossible of stopping the car (or train on the Intamin Coasters), but the car has to stop obviously and that's what the ground is for wiht those hydraulic buffers to soften the landing on the solid ground. (or row of kicker tires on the Intamin Coasters, as running the train into the ground would a very, very bad thing to do)

Since I'm getting tired, I'll point out just a few benefits of magnetic braking...

it is 100% failsafe, it uses no power source what so ever and by the laws of physics will always work, so long as the conductor passes though a magnetic field.(that's where SFNE SROS went wrong). If that fails, we have much more serious things to worry about then your impending freefall death (like the earth loosing it's magnetic poles which is the only thing that can cause them to fail in thoery)

It is 100% maintaince free, no moving parts, no nothing, just make sure the fin is securely attached to the tower and the mangets to the cars and that's it.

That's it, I'm tired.

To sum it all up...

Car goes up, car comes down.

[Aero737]

FParker, that is one of the most informitive posts I've seen on here in a LONG time. Thank you for taking the time to type that out and post.

[Binks Drake]

wow

[w00dland]

That makes me feel a lot safer while riding it. Didn't GD have an e-stop yesterday? How did that work?

[FParker185]

well, E-Stop just stops the Lifting system, if it's dropped already there is no stopping it. I know I saw the catch cars stuck maybe 3/4 of the way down the tower Yesterday (Sat), forget when though, looked as if something was wrong with one of the cars as either car 4 or 5 was parked at the top for the rest of the day.

Forgot one last chapter in my little mini manual there. What happens when it cant lift the cars all the way


Occasionally (usually a power failure mid ride, though I cant say this has happened at SFGAm yet), the ride will stop somewhere besides the top of the tower (where the car unlatching mechanism is), leaving people stuck in places where they'd probably rather not be, procedure for that is for a maintaince person (more than one actually for safety reason) to climb the long long ladder inside the tower to the top, at which point they adorn climbing gear and drop a cable from the top of the tower and they have to repel down to each car and manually unlatch the car (there is a lever type device inside/on each catch car that you can use to manually pull the hook back releasing the cars to fall into the brakes (of if it's still in the brake area to coast slowly to the ground)).

Obviously that is a last resort thing to do. And I'm pretty sure if it were a power failure SFGAm would have a backup power source to raise the cars to the top where the cars would be released normally. Though I could see other things causing a car to stop abnormally and having to resort into repeling (gearbox failure prehaps).

And that completes your lession on Ride Trade Giant Drops 101

[coasterfreak11]

So is the only way the ride can break down is by the lift mechanism then? Because when I was on Hellavator at SFKK it broke right before I went on it. But we got on it with in 10 minutes. And because I know about the magnet brakes, I was not scared of death!
Also, on top of Giant Drop, does it say something to you, because I may have been imagining stuff, but I thought they said something!

[coasterfreak11]

So is the only way the ride can break down is by the lift mechanism then? Because when I was on Hellavator at SFKK it broke right before I went on it. But we got on it with in 10 minutes. And because I know about the magnet brakes, I was not scared of death!
Also, on top of Giant Drop, does it say something to you, because I may have been imagining stuff, but I thought they said something!


Edit: Sorry for the double post, I didn't realize I posted the 1st time....

[twixmix0303]

No they don't say anything.

[FParker185]

I guess I'll add this on, the root cause for so many "breakdowns" on Giant Drops is because of the massive amount of sensors on the ride. Each track has well over 100 sensors (I think number I heard a while back was like 209 or something like that, but I dont remember exactly, and that is each track, so times the number by 6 for the entire ride), while you see alot on the outside of the ride, the vast majority are on the inside of the ride tracking the counterweights, if just one of those sensors malfunctions or the weight passes it wrong and it doesnt register or whatnot, the ride will automatically stop itself and they will either test that car and see if it happens again and if it does they remove it from service(park it on top usually) and let the remaining cars run normally. That's why it's not uncommon to see one or 2 of Giant Drops cars not running.