Six Flags America Accident

[pkd804]

Arn't the brakes suppose to be closed anyways? Thats how trim brakes stop coasters...Duh?

[cpfan101]

Read my post above^. lol. That's all it is, a brake is no more forceful during certain times as weights default the brakes to closed closed but take air preasure to open them (counter balance the weight). That means when closed, they are always closed with the same amount of force. Never more, never less.

--David

[Real]

and how many of have slammed into a closed brake.

 

Depends what ride you have been on. Ive been on, and repeat several rides in which the brakes are closed and remain closed till the ride comes to a complete stop - no tapping, just pure braking. Its not that bad at all.

 

The fluid would suck a bit. Mostly if I was wearing anything decent.

[helix]

.... What I am saying is, everyone is making the assumption that Two Face's trains came down at a normal pace. Yes, brakes are normally in a closed position when you enter the brake run but you glide into a brake run, not come to a zero stop. Look at this video, I don't think I have ever seen a shuttle or invert coaster come back into a station, stop this quickly and at that speed.

[Purplepills]

Where it is the case that you always go into a closed brake, the point being made is that when you hit the brake on the coaster normally, it is more likely at a much lower speed than the train in the video.

 

I have to say it did seem like a fairly sudden stop.

 

And I do also agree with the point made that most of the public don't know anything about coasters. So when something does go wrong, they just think about all the previous sensationalised news stories about how dangerous the things are when they malfunction, which just makes them worry more.

 

It isn't ignorance so much as lack of information, but then a story about how safe rollercoasters are doesn't often (if ever) make the evening news.

[helix]

That is an angle the news media in Washington hasn't covered with this accident. No one has called Vekoma and asked, how is this thing suppose to run? Has anyone checked the Library of Congress to see if there is copy of the Ops Manual on file.

 

Six Flags America has done a safety media event with Fox 5. One of the stations that I feel has been reporting the story fairly. They showed how the P.G. County fire department practices doing an evacuation from the top of Joker's Jinx. Perhaps this would be an area the park could expand on when they reopen the ride. Bring the ride manufacturer, the fire department and others in for a media day and explain what happened, what was done to fix the problem (as well as the one in 2003 and the one in early September) and explain how this coaster works. Perhaps this will help people understand that coasters are safe.

[LcHg5265]

That stop in the station doesnt look much more violent than any E-Stop on a fast coaster or even a standard boomerang.

[RCoasterny]

That sudden stop could be the brakes switching from normal braking to e-stop mode. Vekoma designs their brakes to have two different pressures, one for normal braking and the other for emergencies. The air line going into the control box for each brake is at a very high pressure, well above 100 PSI. In the control box the line splits into two and goes through pressure regulators. One regulator will keep the pressure at a lower pressure and the other will have the pressure at a higher pressure, usually double the lower pressure. A 2 way valve on the lower pressure line opens and closes the brakes. On the higher pressure line, there is a standard valve that only increases the braking pressure, while the valve for the lower pressure line will release the brakes. There is also a reservoir with a check valve that will supply pressure in case the supply line looses pressure.

[LcHg5265]

The only problem i see with your deduction is that vekoma brakes use an airbag system to open (fill up with air), and a "spring" system to close the brakes. (Bent metal forced open when the airbags inflate)

[RCoasterny]

The only problem i see with your deduction is that vekoma brakes use an airbag system to open (fill up with air), and a "spring" system to close the brakes. (Bent metal forced open when the airbags inflate)

 

Nope. You got it backwards. The airbags inflate to close the brakes, while the spring opens the brakes when the airbag deflates. Now if the air line between the valve and the brake's airbags ruptures, the brake will open. However, if it's only limited to one brake, the train will still be able to stop. It'll just take a bit longer to stop, like how your car takes a bit longer to stop in snowy weather compared to dry weather.

[rgb60]

OK, it wouldn't be a fun feeling to be stuck on the lift hill of a boomerang especially facing uphill, then coming down backwards--for 2 hours or was it an hour an a half? How were people on the same train stuck 2 different lengths of time? If news outlets can't get that fact straight, how much credibility does the rest of the story have?

 

But to say the ride went into freefall? No, not exactly, it went down the track. The same track it goes down when the ride isn't stuck. Free fall means nothing but gravity. BTW, I doubt the coaster careened or raced down the hill any faster than it does any other time.

 

Getting sprayed with hydraulic fluid would be a crappy experience-- I admit the quality of the video was pretty bad and I couldn't see anything even with the circle the TV station added. But what is "drenched?" Drenched to me is splashdown ride wet. Is that how wet the passengers were? Or is that just another one of those dramatic TV words they teach anchors to use?

 

Funny thing about the ABC affiliate story-- check out the items below it: 5 school kids shot in Cleveland, DC Gang Wars, an interview with sniper/serial killer John Muhammad. attempted abduction of a 12-year old... and of all those, getting stuck on a rollercoaster is the worst situation?

[Mr.Six]

While although the entire thing doesn't seem like fun. I can't see how the ride itself acted in any sort of an uncommon way. Sure that stop doesn't seem like fun, but being someone who has to safety ride a certain ride daily, I've been stopped from about 20 mph to 0 in about half a second multiple times. Is it fun? No. Is it painful? No. The fluid is the only somewhat interesting part. I know that at rides different fluids spray out all the time, everytime a train stops in station a small bit of fluid will spray out from mutliple locations.

 

I'm no Vekoma expert , so someone correct me if I'm wrong. But I think its very possible that there is always some sort of fluid that sprays out ( in little portions ) whenever that train stops in station. And because the brakes were in an "E-stop" mode the preasure increased along with the amount of the fluid that needs to be expelled.

Just my theory, could very well not be right.

 

_six

[Tmcdllr]

Since the brakes and most everything else except the lift motors is pneumatic which has nothing to do with fluid, its odd that they are saying hydraulic fluid sprayed everywhere. If that happened, where did it come from, somewhere on the lift or something? Or was it just fear and ignorance on the part of the people involved?

[cpfan101]

Nope. You got it backwards. The airbags inflate to close the brakes, while the spring opens the brakes when the airbag deflates. Now if the air line between the valve and the brake's airbags ruptures, the brake will open. However, if it's only limited to one brake, the train will still be able to stop. It'll just take a bit longer to stop, like how your car takes a bit longer to stop in snowy weather compared to dry weather.

 

Sorry but I'll have to disagree with you there as that means the brakes default open. Brakes on roller coasters always default closed. What if the power goes out? By your explanation, all brakes will then default to open.

 

However, the only thing I know for sure is that something caused fluid to leak out and that is all, anyone on these boards knows.

 

However, if there is an expert to Vekoma brakes, please lend us your insight.

 

I think the reason the train stopped so fast in the video was that it was empty. Have you ever seen an empty boomerang? It stops in the station but when fully loaded, it goes all the way out of the station to coast back in again.

 

My two cents

 

--David

[LcHg5265]

I don't know what kind of systems the invertigos use but having been on one, it seems as if its some type of hydraulic motor with chain or a catch car on the inside of a track. The brakes on the invertigo rides are rarely used since upon returning to the station, the train reattaches to the initial lift system and it allows the train to travel up the lift hill as far as it can before it loses enough speed and stops. At that time the system brings the train back down and parks it in the correct position. The brakes open and close every cycle depending on where the train is, but they are not used unless something goes wrong; unlike a boomerang where the brakes are the force used to stop it. The system on the invertigos is alot more complex than the boomerangs.

[sixflagsguy5]

I thought it was really funny how they described it being stuck while showing pictures of the train in the boomerang. People can be so stupid.

[Tmcdllr]

The default on the brakes is closed. The airbags in the brakes are always inflated keeping the brakes closed with compressed air from a resevoir tank, each brake or set of brakes has this tank which has a check valve and is always pressurized from a main supply. The only time the brakes ever open is when the solenoid valves for those brakes are energized which opens them and allows the bags to deflate and the springs to open the brakes. So even if the power goes out the brakes will remain closed as long as the tank has pressure and there is no current to energize the solenoid valves and let the air out. This is why there are resevoir tanks in the first place, as a failsafe to keep the brakes closed if there is a loss of power. That should totally clear this up.

[RCoasterny]

Sorry but I'll have to disagree with you there as that means the brakes default open. Brakes on roller coasters always default closed. What if the power goes out? By your explanation, all brakes will then default to open.

 

However, the only thing I know for sure is that something caused fluid to leak out and that is all, anyone on these boards knows.

 

However, if there is an expert to Vekoma brakes, please lend us your insight.

 

I think the reason the train stopped so fast in the video was that it was empty. Have you ever seen an empty boomerang? It stops in the station but when fully loaded, it goes all the way out of the station to coast back in again.

 

My two cents

 

--David

 

Nope. You're still wrong. How do I know? I used to operate Knoebel's former Whirlwind coaster, which is a Vekoma coaster. The brakes always default to closed as long as there is air in the supply line. That's why I know how Vekoma brake systems works. The Vekoma braking system is actually an Arrow design, just like the train and the track design.

 

Tmcdllr is correct about the brakes. They always default closed in the event of a power failure. We've had power outages at Knoebels due to thunderstorms. Did the train leave the station? Nope. It stayed right where it was. Every night, we shut off the main power to the coaster. No power to the hydraulic systems, air compressors, computer control, etc. Did the train leave the station? Nope. It stayed right where it was.

 

Now David, rather than looking like a complete idiot thinking you are right, why don't you accept the fact that you are wrong, and correct yourself?

 

 

Tmcdllr, I wanted to point out how Vekoma designed the Boomerangs, as well as the Invertigo (Two-Face is an Invertigo). Vekoma uses a hydraulic drive system for the winch that pulls the train up the first hill, and for the chain lift on the second hill. The same is true for the Invertigo. The winch system is in a big box above the station at the base of the hill. Now if a hydraulic line ruptured at the winch system, you can expect a shower of hydraulic fluid inside the station. Hydraulic fluid is the same as brake fluid. If you've read the warnings on a bottle of brake fluid, the same applies to hydraulic fluid. With a running hydraulic system, the fluid can become hot. I can assume that it's no fun to be sprayed with hot hydraulic oil. The news stating that everyone got sprayed with hydraulic fluid was probably when everyone went under the winch with the ruptured hydraulic line and the pump still pumping fluid.

[helix]

 

I think the reason the train stopped so fast in the video was that it was empty. Have you ever seen an empty boomerang? It stops in the station but when fully loaded, it goes all the way out of the station to coast back in again.

 

My two cents

 

--David

 

The train wasn't half empty. I was at the park, saw the coaster stuck on the lift and can tell you the train wasn't half empty. What would give you that impression?

[Tmcdllr]

Rcoasterny, thanks for the info. I knew my explanation was correct from experience. I too used to operate an arrow coaster and the brakes are pretty much the same as you stated. I can also say what you are saying about how the brakes on your coaster etc., is also true. Invertigos I know have the same brake systems but wasnt sure about the lift. Thanks for clarifying where the hydraulic fluid could have come from, it makes sense now.

[jarmor]

It's amazing I post this video

and get personal messages about how I don't "get it" about the coaster being unsafe and I must work for the park and all kinda crap. I even had one person go as far as leaving a meassage calling me a b!tch.

 

Jarvis "in 2 months this will be a thing of the past" Morant!