slosprint wrote:
While I understand where you're coming from, and respect your experience in the industry and knowledge of these topics, I think this might be a sign that its time to update these systems. Let's face it, when an accident happens in the airline industry, measures are taken to ensure that the same problem never happens again, for instance when a hornet made a nest in a Pitot tube of an airline, causing the pilot to get faulty readings and crash the plane, the co-pilot was getting accurate readings from his own tube. This made it standard to not only install several more redundant tubes to future airlines, but make it so the crew could choose exactly which tubes' readings to display in the cabin.
While this kind of accident is unique, unless measures are implemented to prevent it happening again, probability states that it WILL happen again, maybe not in this decade or the next, but again nonetheless. Using another airline example, just look up the cargo door issue on DC-10s.
I'm not trying to be alarmist, but rides are getting more and more complex in terms of components and number of trains, and issues like this are sure to arise again. You've seen how panicked this has caused the public to be about ride safety, and it is clear that they hold the amusement industry to a MUCH higher standard than pretty much any other. Hell, tens of thousands of people die on the road in the US alone every year, and yet the one major accident in amusement parks this year which i can name, which resulted in no fatalities, has the public in an uproar demanding the ride be torn down. Instead of calling them panicked and unreasonable (which they might be), I think it's entirely possible to meet the standards which they put up, and to be honest I think that would be better for everyone.
Aviation and the Themed Entertainment Industry share a lot of the same problems but seek different solutions as a result of the lack of oversight in most jurisdictions in relation to the operation of rides. In the US, there is no FAA equivalent investigating accidents except for the tiny fraction of accidents investigated by OSHA. Airbus recently had a fatal accident related to engine control software which resulted in three out of four engines operating at reduces thrust resulting in the loss of airframe.
This situation is once again a subjective one, how we leverage automation and computer technology within a given field. Airbus believes the computer is always right, and that it should over ride the pilots authority when ever it feels the pilot is operating outside a given set of parameters. Boeing believes the pilot has the final say, and the computer at anytime can be told to sitdown and shutup. There are of course some aircraft manufacturers out there that would let you fly straight into the ground with out so much as a beep, but then again I guess they figure the pilots wont be able to hear the warnings above the screams of their passengers.
In our industry we leverage automation to handle the basic operation of the ride. Once a train is loaded, checked, and dispatched the computer is handling it from there until it gets to the end and stops and is approved for parking by the operator. It would seem though that some of the industry is forgetting the roots of the very systems that we employ, these systems were designed to assist a properly trained operator during routine operations. They were never designed to prevent someone who should know how the damn thing works from operating in a mode that allows the computer to deviate from routine operations with out warning or interruption.
Each year this industry trys to spend less money on training hours and has failed to accept that newer generations of operators are in fact dumber then in years past. This isn't helped by automated HR screening utilities employed by a number of organizations that actually weed out intelligent employees. They don't want the liability of someone smart figuring out that something is wrong, documenting it escalations it, and then when there is an accident the liability from failing to act on such information.
This is not a failure of existing ride systems, this is a failure to understand the trends that are ongoing in this industry and a systemic and systematic failure by the industry to address these problems at the correct level. We can throw more complex computer systems at these guys, but then when a different situation arises you only have a more complex system in which to troubleshoot, maintain, and operate. Imagine what would happen if you were trying to handle an accident investigation on a much more complex system where development mistakes could result in fatalities.
Disney has been running ride control systems longer then anybody. They invested in and built the first redundant PLC implementations and they understood the limitations and benefits of the system. They know that when they get a cascade failure that they are going to have to send someone to locate every train and clear every block in sequence to insure a safe start up. This expectation is outlined in the SOP. Disney ride operators are held to a much higher standard then those of other parks. They are operating a much more complex system that allows the operator a lot more freedom them control systems and policy frame works in other organizations. They are essentially working in a semi-automatic mode and they still have the lowest incident per cycle count rates in the world.
Each year this industry hires high school and college students most of whom have never had a full time job and we expect them to operator a very expensive and dangerous piece of machinery in climates of varying extremes for long hours and little pay with minimal training. They are considered expendable and the seasonal turn over rate is close to 45%. Most full time operators split the year into two six month seasons. Employees are terminated at the six month park and they can re-apply after six months. The turn over rate is so high, that it is hard to pass knowledge down from one generation of operators to another. If important information is missed in training, which I should mention not all of the training is absorbed anyway by the trainee, then you really are placing a very heavy burden on the automatic systems that are controlled by the very poorly informed teenager at the controls.
In short, stop blaming the computer and stop trying to put the computer in charge of more things because its only going to perpetuate the cycle of stupidity. It's not it's fault there's a loose nut behind the main operator panel.
Coasterkidmwm wrote:
The schwarzkopfs used a similar or more primitive system on their rides that were capable of running 6 goddamned trains at once. I don't see how number of trains would be an issue here.
The older simpleton rides had a simple four way relay that was quite engenuis, the previous block could only be engaged by a switch hit by the train exiting the block after it. It was quite a reliable system because it was so simple. Almost as good as a mechanical interlock.
tiepilot35 wrote:
Mikey do you think it's at all possible that this system is almost too new? Like maybe they tried to use a different kind of control system than the industry convention? It seems to have been having a lot more problems than most coasters, even compared to the breakdown kings at cedar point. Just wondering.
Also. I highly doubt they will "scrap" it. An ???18 million brand new steel roller coaster won't get demolished. It simply won't. It very well may stand SBNO until the hype dies down in two and a half weeks and a serious computer system overhaul is attempted by Gerstlauer or someone else. This might give them the window they needed to attempt a system reliability improvement. It'll open back up to the public--I have to ride it! People will still ride it. *Hopefully* it will end up being like RCT where people will just stand there saying "I'm not going on The Smiler--It isn't safe!" even though all coasters with two or more trains have roughly the same risk of something like this happening. This way, the line will be shorter!
There is no official standard on makes and models of PLC that are specified for process controls. I have worked ride control systems by Siemens, Allen Bradley / Cutler Hammer, DirectLogic/Koyo, they are functionally the same and use the same programming languages for the most part. I know of a few custom installations that are using PC to IO cards to allow a custom application to handle some I/O capability but am not certain they are using that to actually operate the ride instead of logging certain data separate from the main computer.
Most newer rides employee multiple PLCs operating in parallel for redundancy with node majority or a primary PLC and Safety PLC setup where one watches the other to make sure it's working as it should. I don't think they will scrap it, I think they will likely need to re-engineer the section of track that it keeps getting stuck on. I would like to think that it was probably notated during the acceptance testing and since it now a line item in a sequence of events letting to a collision that something will need to be done about it.
I would also like to think they will put the bumpers on the front of the cars on smiler like they do on the back. While these are not designed to do anything in a high speed collision, they are quite effective in cushioning a small collision. I would say that the reason the second train suffered so much damage, to an extent the floor buckled on the poor thing, is that bumpers were not installed on front and back of the trains. From the pictures that I can see on google, I dont think the trains have ever been equipped with front bumpers.
That reporter was very wrong for trying to invoke such a response out of the Alton Towers rep, it is quite clear that she is attempting to invoke a poke the bear response using sensationalized journalism. This was an accident, while from a legal standpoint I am sure Alton Towers is to blame, I think that they are handling this incident appropriately. I haven't seen any reports about why the other rides are closed, but my guess is that these rides may feature control systems supplied by the OEM or designed by the OEM which are more simpleton when it comes to operating in a manual or maintenance override mode.