Alton Towers Discussion Thread

[KarlaKoaster]

That's interesting (and very believable!). I know I'd be trying to tell a member of staff if I saw it.

I hope this doesn't make me sound like a horrible person, but if I saw a stalled car on a coaster, I don't think I would tell a member of staff as I would assume that they would be aware of the situation and working to fix it... and I certainly wouldn't think that the ride could be dispatched and then crash.

I've read various reports that seem to explain things, but leave out a few details that I'm wondering about.

 

1) The train with the passengers, sat on the first(?) lift hill for 5-15 minutes. Was it in fact the first lift hill, or the second or a brake run?

 

2) While it was sitting, this means the empty train would have been stopped somewhere as well. Was it on the second lift hill or a brake run, or had it already valleyed and sitting at the bottom of the batwing?

 

3) Ultimately, the question for me is where was the empty train when the first was released from its hold position?

If it had already valleyed, then clearly, maintenance screwed up by not doing a visual check and then releasing the loaded train. But, if it was stopped at another section, then valleyed after being released, then that would point to a block not being registered and/or a brake section that failed when it should have stopped the loaded train.

 

4) One more question. I have a basic understanding of how blocks work on coasters, and sensors indicate when a train rolls past one registering that it has passed that section. But, what happens when a valley occurs and it rocks back and forth over the same sensor? Could the sensor/computer have registered the empty train as being past that block, but not been able to detect the rollback?

 

Most coasters in general use sensors only around block areas (Near lifts, brakes, etc.). It is a rare occurrence for sensors to be used midway through a ride (cost is a big factor, and they aren't really necessary). There probably was not a sensor in that area, so the train wasn't detected. So unless maintenance overrode the error, there is a good chance that they overlooked the train and switched the train dial thinking an operator accidentally touched it.

 

I don't think you understand how a block system works. A coaster is split up into block zones such as a lift, mcbr, launch, etc. Each block zone has a number of sensors that detect when a train is entering and exiting a block zone. For instance, on a MCBR there would typically be a sensor at the beginning and end of the brake run to know that the train is exiting the previous block and entering the next. The PLC will keep track of this up until the next block zone when it will flag another sensor and let the PLC know that the train has left that block zone and the next train is free to proceed. If that train doesn't flag the next sensor, the train behind it is told to stop at the next previous stopping point before the next block to ensure there is no collision.

 

Just because there are no sensors in the batwing does not mean the PLC doesn't know where this train is. All the PLC needs to know is that a train has entered a certain zone and whether or not is has left yet. If the reports of the train stopped on the lift are true, that means the PLC did in fact know that the stalled train never left the block zone after the lift and was told to stop. Just about every roller coaster in existence follows this principle. Some more advanced rides like you would find at Disney/Universal utilize hundreds of these sensors to track ABSOLUTE position of every vehicle on the track. This is a more advanced (and costly) way of creating block zones.

 

Also, from my experience I've seen some coaster control systems utilize a timer for block zones. Basically what happens is the designer will dictate how long they would typically expect a train to be within a certain block zone and add some sort of additional time on top. If a sensor isn't flagged within this amount of time after flagging the previous sensor, it would typically throw a fault in the system and bring the ride to a stop. This is the way a system knows whether or not a sensor is failed and is another safety measure put into place into ride systems.

I think you might have misread his post because I think they understand that, they just were responding to grumpyfan by explaining that the sensors are normally only on things like mid-course brakes, lifts etc, that if a train valleys it won't keep rolling backwards and forwards through the same sensor because they're not normally installed randomly around the track on things like the batwing. There are of course exceptions like I think there is one on Rita just after the crest first hill so that the ride knows the train has successfully launched and cleared the first hill.

Edited June 5, 2015 by KarlaKoaster

[WindexCyanide13]

When the ride reopens, two of the trains definitely need some fixing. Could it be possible for Gerstlaur to give them a discount on the lap bar only infinity train? It would improve ride experience and make guests know that they put a lot of work into it running again.

[KarlaKoaster]

When the ride reopens, two of the trains definitely need some fixing. Could it be possible for Gerstlaur to give them a discount on the lap bar only infinity train? It would improve ride experience and make guests know that they put a lot of work into it running again.

Alton didn't want the lapbar only trains to begin with so I don't think they would install them just for public peace of mind. If anything it would spook people further having seen comments on Facebook when the ride first opened where enthusiasts were saying 'hi Alton why didn't you get the lapbar version of the train' and people were basically saying 'WTF OMG it has 14 loops, are you crazy?'

[thedazza]

When the ride reopens, two of the trains definitely need some fixing. Could it be possible for Gerstlaur to give them a discount on the lap bar only infinity train? It would improve ride experience and make guests know that they put a lot of work into it running again.

 

I think we can probably say that in this accident having OTSRs most likely saved lives, if it were lapbars the front row passengers would all most probably have gone face first into the stalled train. I don't think it is going to reassure the GP of the rides safety if a ride they deem to be unsafe re-opens with just lap restraints.

[Purplepills]

^Very true.

 

Immediately after the crash, the guy on the far left seat had blood all over his face as if he had hit something as it was. I'd say with confidence you'd probably be looking at fatalities had the train only had lapbars. See the video HERE to see just how close the riders are to the train in front.

[T-Dawg]

That's interesting (and very believable!). I know I'd be trying to tell a member of staff if I saw it.

I hope this doesn't make me sound like a horrible person, but if I saw a stalled car on a coaster, I don't think I would tell a member of staff as I would assume that they would be aware of the situation and working to fix it... and I certainly wouldn't think that the ride could be dispatched and then crash.

 

No I'd understand that, not a horrible thing at all, you'd certainly be completely reasonable to expect them to be aware and fixing it, and I'd certainly expect to be told "yeah we know how it works thanks" if I mentioned it, I'd just be paranoid with the second car lurking on the lift hill (even more so now!). Must've been a heart sinking moment when people saw it move forward

 

When the ride reopens, two of the trains definitely need some fixing. Could it be possible for Gerstlaur to give them a discount on the lap bar only infinity train? It would improve ride experience and make guests know that they put a lot of work into it running again.

 

I'm a huge fan of lap bars on big rides (always love riding Shambhala at Port Adventura and Nitro at Six Flags Great Adventure), but having ridden Smiler countless times - I don't think I'd be particularly comfortable riding it with lap bars with the inversion forces it's got, even before the crash. Like other people mentioned, if they had lap bars on when this crash happened the injuries would've been even more brutal. When I've ridden Smiler with non-coaster enthusiast friends they've always held on to the restraints for dear life even with the over-shoulders and me shouting "Hands up! Whooo!" and not holding on at all, don't think GP would take lap bars as an improvement on this particular ride

[Imiha]

it just sounds like this ride is really unsafe weth all these crashes and maintainances stops. that one thing i hate about alton towers theres always a couple big rides down whenever i go. mostly AIR

Divertical (Intamin) at Mirabilandia had a lot, a lot of problems. The ride was down a lot of the time, last year a train got stuck at the section of the track and riders had to be rescued from the middle of the track, it will reopen in a few days. I don't consider this coaster unsafe because of all the problems. It didn't cause any injuries or anything that could be seen as dangerous or unsafe. It is unreliable though and that's what I would also call The Smiler.

Also only one crash and everything points that it was a human error so it could have happened on any ride. If anything I will consider The Smiler to be much more safe with all the investigations and staff training going on.

[CoasterLine]

The only possible way I could see the ride ever being removed from the park is if the entirety of the "final report" comes to light that the accident was caused 100% by the computer / operations system. At that point, you could see lawsuits from Alton Towers / Merlin against Gerstlauer for liability, damages, etc. to recoup the money invested into a faulty product. At this point, there really isn't much suggesting that this was anything other than human / user error.

 

That being the case, unless there was a huge backlash from the public and subsequent loss of profit or drop in attendance because the "ride is still there", there is no reason for them to remove the ride and lose that much of an investment. Economically, there is literally zero to gain by removing it.

[KarlaKoaster]

it just sounds like this ride is really unsafe weth all these crashes

'All' these crashes? It's only had one?

 

and maintainances stops.

This is the ride/computer doing what it should do and stopping if it is ever unsure about anything.

 

that one thing i hate about alton towers theres always a couple big rides down whenever i go. mostly AIR

Expect this even more as the park will be super careful and incredibly cautious from now on. Not saying that they weren't before, but even more than ever they will err on the side of caution.

[grumpyfan]

I think I'm kind of with Robb on this, but can everyone just stop with ALL the speculation on Smiler being removed? It's not even pertinent to the discussion right now. First, they need to understand what happened, then decide what can be done to prevent it from happening again. Sure, it's had a few (very public) operational issues and stalls, but nobody has been killed on it. Not that this is the measure by which an attraction should be removed, but as pointed out, there have been many others where people were killed on, and the attractions are still operating today (Disney has a few). I feel pretty confident in saying, whatever happened, be it human error, ride/computer malfunction or almost anything else, it can still be fixed or improved to prevent the situation from recurring and the ride will be even safer than before.

[robbalvey]

it just sounds like this ride is really unsafe weth all these crashes and maintainances stops. that one thing i hate about alton towers theres always a couple big rides down whenever i go. mostly AIR

This post was written by a spammer. Very clever, but it's not real. Please ignore. Account has been removed.

[robbalvey]

If they are talking about "procedures" would that tend to suggest human error was the cause?

Yeah, I'd say that statement from Alton Towers along with the fact that they are closing other rides that are not Gerstlauer rides pretty much confirms what we had thought. I mean, outside of some absolutely crazy computer programmer glitch, human error is pretty much the only scenario that makes sense.

[gerstlaueringvar]

Forget about the lap bar people, I'm very glad Smiler has those OTSR's because they saved lives. For a crash like this, not only OTSR's can keep the riders' upper body from violently moving forward, a lap bar like those on the other Infinity Coasters is going to dig right into the rider's belly and cause probably immediate death. See how bent the floor of the first car is, the hydraulic lock devices are at the very front of the car so that's the first thing that will be pushed back. I actually think Gerstlauer will make some modification to their future Infinity Coaster trains and start using the DDD style lap bar again.

[Sprint390g]

The BBC news just showed an airel shot with the two cars now separated and it looked the front car's bar had concaved into a v shape which seemed to go quite far in.

[T-Dawg]

The BBC news just showed an airel shot with the two cars now separated and it looked the front car's bar had concaved into a v shape which seemed to go quite far in.

Yeah I suspect that will be the protuding bump stop from the back of the car in front piling into (or really being piled into by) the middle of the car behind... I did have a worry that might happen - really not designed for high speed impacts at all

 

So actually, the little bump stop possibly made the accident worse by focussing the energy on that single point and caving the bar in, rather than if it was flat and spread the energy over a large surface area (could've still reduced the energy slightly being made of rubber though). Hrm...

[UKCoasterFan]

Nick Varney has been on tonight's BBC news talking a little more about the accident. For all those that are not in the UK and want to hear what he had to say, the interview can be seen here:

 

http://www.bbc.co.uk/news/uk-england-33025024

[robbalvey]

The BBC news just showed an airel shot with the two cars now separated and it looked the front car's bar had concaved into a v shape which seemed to go quite far in.

Any pics?

[coasterkid124]

4) One more question. I have a basic understanding of how blocks work on coasters, and sensors indicate when a train rolls past one registering that it has passed that section. But, what happens when a valley occurs and it rocks back and forth over the same sensor? Could the sensor/computer have registered the empty train as being past that block, but not been able to detect the rollback?

 

Most coasters in general use sensors only around block areas (Near lifts, brakes, etc.). It is a rare occurrence for sensors to be used midway through a ride (cost is a big factor, and they aren't really necessary). There probably was not a sensor in that area, so the train wasn't detected. So unless maintenance overrode the error, there is a good chance that they overlooked the train and switched the train dial thinking an operator accidentally touched it.

 

I don't think you understand how a block system works. A coaster is split up into block zones such as a lift, mcbr, launch, etc. Each block zone has a number of sensors that detect when a train is entering and exiting a block zone. For instance, on a MCBR there would typically be a sensor at the beginning and end of the brake run to know that the train is exiting the previous block and entering the next. The PLC will keep track of this up until the next block zone when it will flag another sensor and let the PLC know that the train has left that block zone and the next train is free to proceed. If that train doesn't flag the next sensor, the train behind it is told to stop at the next previous stopping point before the next block to ensure there is no collision.

 

Just because there are no sensors in the batwing does not mean the PLC doesn't know where this train is. All the PLC needs to know is that a train has entered a certain zone and whether or not is has left yet. If the reports of the train stopped on the lift are true, that means the PLC did in fact know that the stalled train never left the block zone after the lift and was told to stop. Just about every roller coaster in existence follows this principle. Some more advanced rides like you would find at Disney/Universal utilize hundreds of these sensors to track ABSOLUTE position of every vehicle on the track. This is a more advanced (and costly) way of creating block zones.

 

Also, from my experience I've seen some coaster control systems utilize a timer for block zones. Basically what happens is the designer will dictate how long they would typically expect a train to be within a certain block zone and add some sort of additional time on top. If a sensor isn't flagged within this amount of time after flagging the previous sensor, it would typically throw a fault in the system and bring the ride to a stop. This is the way a system knows whether or not a sensor is failed and is another safety measure put into place into ride systems.

I think you might have misread his post because I think they understand that, they just were responding to grumpyfan by explaining that the sensors are normally only on things like mid-course brakes, lifts etc, that if a train valleys it won't keep rolling backwards and forwards through the same sensor because they're not normally installed randomly around the track on things like the batwing. There are of course exceptions like I think there is one on Rita just after the crest first hill so that the ride knows the train has successfully launched and cleared the first hill.

 

Yeah, I know how block systems and PLCs work, I was just bringing up the point that sensors are usually located around blocks, not in random elements of the ride. However, maintenance mode can pretty much override anything, so even if the PLC had an idea of where the train was, a push of the reset button or alarm silence could have cleared it.

[UKCoasterFan]

You can watch the full news report here Robb:

 

http://www.bbc.co.uk/iplayer/live/bbcnews

 

If you are unable to view it (not sure if there are any country restrictions on BBC news), I can take some photo's of my screen and upload them somewhere for you. The fly over happens between 18:01 and 18:02. Its not the clearest footage, but if you pause it in the right place, you can see the front of the second car.

[lewis97]

Best screenshot I could get.

BBC News aerial footage of The Smiler trains removal

[gerstlaueringvar]

This is way too rude to Merlin! http://www.snappytv.com/tc/628458/157163

[KarlaKoaster]

Sky is such an odious organisation and she is a horrible person with previous form. I'm glad most people on Twitter of all places seem to agree.

[coasterkid124]

That news reporter really shouldn't have a job. Varney clearly is stating that the ride was definitely safe before the accident, but a unique set of circumstances lead to the accident. Plus, some new safety protocols will be added to ensure that an accident like this will not happen again. If people should get mad at anyone, it should be whomever was operating the ride, considering this of course was human error. There is no reason to have the ride in maintenance mode if people were aboard. Plus, the batwing and trains should have been monitored before moving anything.

[Purplepills]

The BBC news just showed an airel shot with the two cars now separated and it looked the front car's bar had concaved into a v shape which seemed to go quite far in.

Yeah I suspect that will be the protuding bump stop from the back of the car in front piling into (or really being piled into by) the middle of the car behind... I did have a worry that might happen - really not designed for high speed impacts at all

 

So actually, the little bump stop possibly made the accident worse by focussing the energy on that single point and caving the bar in, rather than if it was flat and spread the energy over a large surface area (could've still reduced the energy slightly being made of rubber though). Hrm...

 

This is what I thought when I Googled the Smiler cars just after the accident. You could see the front was at quite angle in a couple of the accident photos. Given the back has a massive stop on as below, its unfortunate that its caved the front of the second train in rather than the back of the stationary one.

 

 

 

I wouldn't be at all surprised if The HSE suggest/insist the design is changed - after all, if it was a different design the injuries sustained could've been reduced hugely. I know the design wasn't supposed to withstand this amount of impact, sadly now it has happened they may insist further precautions are taken.

[grumpyfan]

Wow! She is really nasty, and annoying. Is she related to Piers Morgan?

 

Edited June 5, 2015 by grumpyfan