Expoland Roller Coaster Accident

[Tsuru]

Jesus fucking Christ.

On second thoughts I'm pleasantly surprised that the news of the maintenance fuckups came out so quickly. Very un-Japanese. Now is the time to put the assholes in charge away for fucking life.

No payoffs, no NHK apology, just good old-fashioned lifetime sentences. 20-something people now have to deal with nightmares of 300 pounds of girl being minced before their eyes for the rest of their lives. The only consolation I can think of is that death for the poor young girl was probably instantaneous.

[Doctor Stop]

You know that's not the Japanese way, Tsuru. Those responsible probably won't pay any price, other than have to give a public apology and afterwards receive a sideways promotion. The best bet in Japan is to blame it on someone who's retiring this year anyway. Any financial settlements will likely be more than offset by the money saved by skipping out on maintenance. Now, if protesters were to occupy Expoland until justice was done...sorry, I forgot this is Japan.

風神雷神II (Google cache)

Amusement Ride Accidents & News (this incident's not up yet):
http://amusementsafety.org/

[Tsuru]

You know that's not the Japanese way, Tsuru.

Wishful thinking...

[Doctor Stop]

Think of the wa.

[Mulboyne]

Amusement Ride Accidents & News (this incident's not up yet):
http://amusementsafety.org/

This one is up to date. I checked a few roller coaster forums. The roller coaster fans were all shocked about the accident but were astonished that the problem was as simple as maintenance. They were worried that it was a design issue.

I won't defend someone skimping on an elevator check but the typical elevator in a typical mansion is unlikely to get intensive use. Why the hell someone decided that a theme park attraction in constant use and subject to outdoor elements could be overlooked is beyond me. I saw on the news that the operator submitted a report to local authorities saying that the ride had passed all checks. However, it seems that they did not carry out mandated checks so the report was false. The operator has been quoted as saying that they were not aware that certain checks were mandatory.

I mentioned before about how problems with maintenance have become more public. I wonder whether this issue will calm down quite so easily. The girl who died has received coverage not far short of the JR Amagasaki victims so I'm not sure the affair will be settled as smoothly as it might have been in previous years.

[Kuang_Grade]

It was interesting to see the picture the victim's family used at her funeral...The young woman in casual dress and wearing a baseball cap with the brim to the side. Not the typical stoney faced J funeral portrait.

As for the level of news coverage, I suspect that some of it has to due with the nature of the story but also since it happened during golden week, so it fits the "season" as well as the fact that it is likely a pretty slow week for new.....(Fuji TV, in their coverage of the various things people were doing during golden week....being stuck in traffic jams seems like a holiday favorite...even did a helicopter shot of the line outside Krispy Kreme Donuts in Shinjuku and then had a inside shot with a reporter taking the most inept donut bite I've ever seen), so the gutsy daikon stories aren't pushing it out of the spotlight.

[GomiGirl]

I checked a few roller coaster forums. The roller coaster fans ......

There are roller coaster forums? More than one? There are roller coaster fans? Wonder what their secret handshake is like???

[kamome]

[quote="GomiGirl"]There are roller coaster forums? More than one? There are roller coaster fans? Wonder what their secret handshake is like??? ]

Yeah, a friend of mine actually belongs to one of those groups. He and his wife visit all the roller coasters at different theme parks around the world and check them off a list. I think it's kind of an otaku thing.

[Doctor Stop]

Amusement park boss deemed flaw test of roller coaster axles was not urgent
SUITA, Osaka -- Mechanics at an amusement park, where a woman died and 19 were injured when a roller coaster broke an axle and derailed, chose not to conduct a axle inspection in January after their boss deemed it not urgent.

"We only learned that it's compulsory to conduct flaw tests (to see any invisible cracks in roller coasters) under the Japanese Industrial Standards (JIS) after the accident. None of the 24 licensed mechanics in the company knew that either," said Jun Tatebe, who heads the technical division of Expoland in Suita.

http://mdn.mainichi-msn.co.jp/national/news/20070509p2a00m0na004000c.html

[dimwit]

I was having a very interesting conversation with an engineer about this story and one of the interesting things that he came up with is that roller coasters are regulated as structures rather than forms of transportation. The difference being the safety regulations involving structures are more concerned with contruction (deadweight, live weight, wind shear, strength of the materials, etc.) whereas transportation has to concerned not only construction but also dynamic stresses which occur regularly.

[emperor]

http://thedivinewind.ytmnd.com/

[james]

..deadweight...

well they've certainly managed to come up with some of that.

[Taro Toporific]

[Captain Japan]

These two quotes are interesting...

"We only learned that it's compulsory to conduct flaw tests (to see any invisible cracks in roller coasters) under the Japanese Industrial Standards (JIS) after the accident. None of the 24 licensed mechanics in the company knew that either," said Jun Tatebe, who heads the technical division of Expoland in Suita.

Expoland usually disassembles roller coasters in January or February to check if any cracks have been caused inside vehicle components by using ultrasonic and magnetic wave devices, according to company officials. This year, however, the annual checkup had been put off until May 15, after the Golden Week holiday period, because of a lack of space needed for disassembling, they said.

I think the key word is "compulsory." As Taro has said before in this forum, standards that aren't eforced aren't standards. In the second quote, does this mean, they check for cracks sometimes?

In any case, Tsuru has given the best analysis of the situation. Steel will fail after a certain stress has been placed upon it a certain number of times, referred to in the biz as "cycles." Of course, the critical relationship between stress and cycles depends on the type of steel, but usually designs for things like bridges (where cars are traveling above) would call for the number of cycles to be in the hundreds of thousands (that would be using the US ASCI standard; in this case, the standard would be Japan's JIS, which is usually considered to be an equivalent). For a rollercoaster axle, I don't know what the design would call for. But it is safe to say that the excuse of not knowing it is "compulsory" is absolutely ridiculous.

As well, I don't know that using the word "flaw" is the right word. That, to me, assumes that the steel was not manufactured properly, which is most certainly not necessarily the case here.

[Hokuto-shinken]

[SIZE="1"]The poor girls head was taken straight off.　People are saying she is too fat, but if the Roller Coaster does not have any weight restrictions, the theme park is to blame. [/SIZE]

[Blah Pete]

[FG Lurker]

No way she was too heavy. They must spec those cars way over what a human would weigh.

It could just have been coincidence that the time the 300lb (or whatever she weighed) woman rides the coaster bits of her car break... Or it could be that the cracks were starting to get bad and the extra strain pushed it beyond limits.

In any case simple preventative maintenance could easily have stopped this from happening. Would be great to see some criminal charges laid...

[Hokuto-shinken]

I think Japan has strange censorship rules. In magazines you can`t show some peoples faces, you can`t show male and female private parts but you can show parts of this girls dead body.

I do think emperor`s Avatar is not suitable for this thread.

[Greji]

II do think emperor`s Avatar is not suitable for this thread.

Na, that's all right! His avitar is based on the elite cram school course in downtown Aizuwakamatsu, Fukushima.

[Tsuru]

Or it could be that the cracks were starting to get bad and the extra strain pushed it beyond limits.

In any case simple preventative maintenance could easily have stopped this from happening. Would be great to see some criminal charges laid...

If by "preventive maintenance" you mean replacing the load-bearing structure in the cars when cracks are found, then you would be correct.

The relationship between the forces and the number of times you can apply the same force until the structure fails through fatigue cracking is displayed in a so-called S-N curve:



While the maximum amount of stress in MPa or kpsi* the structure would be able to handle in any point of its service life is not shown, the relationship between the average amount of stress in MPa or kpsi** and the maximum lifespan is clear for all to see. So yes, metal structures get weaker over time and this girl's ride probably pushed it beyond limits. Note that the horizontal axis is exponential rather than linear, and that this graph does not account for simple environmental corrosion, stress corrosion or simple wear-and-tear. Especially stress corrosion would be a major compounding factor in a rollercoaster. The expo-land axle would have been somewhere between 10^4 and 10^5 cycles.

*) The difference between the maximum weight of a heavy girl multiplied by the minimum and maximum load factor or G-force that would cause the structure to fail, divided by the area of the load-bearing structure crosssection.

**) the difference between the maximum weight of an average Japanese person multiplied by the minimum and maximum load factor or G-force that would cause the structure to fail, divided by the area of the load-bearing structure crosssection.

MPa (Megapascals, or 1 million newtons per square meter) is the SI equivalent of English kpsi (1000 pounds per square inch)

[Captain Japan]

[Doctor Stop]

Crack found in 2nd coaster at Expoland
Daily Gomiuri

A second roller coaster train at Expoland park amusement park in Suita, Osaka Prefecture, which ran alternately with one that fatally derailed in May allegedly due to a cracked axle, had a similar crack in one of its axles, police said.

The police say the crack on one of the second train's axles is discernable by the naked eye and they expressed concern the ride could experience a similar deadly accident if the axle breaks.

I thought the only place you could score some crack in Osaka was in Amerikamura. Imagine the chances of the cops finding someone's stash hidden not in one, but in two roller coaster cars.

[IkemenTommy]

Crack found in 2nd coaster at Expoland
Daily Gomiuri


I thought the only place you could score some crack in Osaka was in Amerikamura. Imagine the chances of the cops finding someone's stash hidden not in one, but in two roller coaster cars.