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Another English/Metric "Spacecraft" Problem
SuperDry writes "There's been another spacecraft failure that's been attributed to an English/Metric units problem, this time at Tokyo Disneyland's Space Mountain. An axle broke on a "spacecraft" (a.k.a. roller coaster train) mid-ride, causing it to derail (nobody was hurt). The final investigation report has been released, and the root cause has been determined to be a part being the wrong size due to a conversion of the master plans in 1995 from English units to Metric units. In 2002, new axles were mistakenly ordered using the pre-1995 English specifications instead of the current Metric specifications. Apparently size does matter, even if it's only a 0.86mm difference."
It's more like an English spelling problem, no?
I could care less, but not without a lobotomy
How come everything Disney does ends up so Mickey Mouse?
The Japanese who, like the rest of the modern world, switched to metric years ago?
Or the American designers who couldn't even do simple multiplication in order to convert from English to Metric?
I have been pwned because my
I'm Canadian, so I have to assume that 'proble' is the... imperial spelling... of problem?
"I get five rods to the hog's head!"
If Jesus wants me it knows where to find me.
We need a one world government with one way of doing things! How many more people have to die because we have to hang on to old ways of doing things? Stop this madness now! Surrender your nationalist ideals. Borders exist in the minds of dimwitted politicians. Borders can't be see from space. We must unite and work together to advance mankind.
Support the New World Order now!
From the Article:
In September 1995, the design specifications for the size of the axle bearing for Space Mountain vehicles was changed from inches to the metric scale. Accordingly, the axle diameter was also changed, in this case from 44.14 mm to 45.00 mm. However, appropriate action to revise and maintain the design drawings was neglected. Consequently, two different drawings existed within our company after the changes were made and the old drawing showing the 44.14 mm diameter was used to order (in August 2002) the axles that were delivered in October 2002.
They actually changed the specs. The conversions were all done correctly but they failed to update everyone.
I don't know about you, but us English call the measurement system the Imperial system. Isn't the American version slightly different, in respect to fluid units, etc?
Why do you call them 'English' units, when everyone else knows them as Imperial units? :-) We stopped using most of them some time ago.
It wasn't mentioned in the article, but for my own reference, I'm wondering how many Rods to the Hogshead this ride gets?
Or if that info. isn't available, how many stone per fortnight this ride has in lifting capacity.
TDz.
In the automotive industry being off by that 'gigantic' mile of a discrepancy can be the difference between an entirely safe system or a potentially dangerous event just waiting to happen.
Anything from rubbing away the lining of important wires or hoses, different stress locations resulting in tear apart pieces that shouldn't be tear apart can happen by being off by that much...
0.86mm might at well be 3 feet off. A part that comes out that far off is nothing but scrap material. (Well at least in our area of automotive work.)
If you ignore the other uses of a tool, does that make the tool less useful, or you less useful?
Proving once again that the average person has a hard time coutning to ten.
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
Please don't say English/Metric units. The UK is effectively metric now, all schoolchildren are only taught metric units and everything has to be priced in metric units. I don't even have intutitions about how long feet are or how heavy a stone is. Pretty much everyone under the age of 25 only deals with litres, metres and kilograms. The only exception is vehicle speed, which is still measured in mph (and hence all our road signs are in mph). You won't, however, catch any British Engineers or scientists using Imperial units.
Better ways to describe them would be "Imperial" (what we call them), "American" or "Archiac". I think it's about time the US caught up with the rest of the world and ditched these stupid and difficult-to-remember units once and for all.
>Apparently size does matter, even if it's only a 0.86mm difference. At this very moment there are hundreds of geeks around the world trying to think of a great punchline for this.
Left 4 Dead Gaming Group - http://www.l4dgg.com
If you had read the article, you would know that the problem was, while converting to metric, they also changed the specification of the axle size, but didn't record the new axle size correctly. So, the problem really had nothing to do with any mathematical error, just an error in incorrect documentation.
A modern day witchhunt.
And suddenly the mods realized that "Problem" was fixed and they'd blown all their mod points on two-minute jokes.
Google's Cache is here.
The US needs to catch up to the rest of the world. The entire world uses Metric people. And it makes an infinite amount more sense to use Metric than the US system. If we don't, trade will continue to suffer as well as accidents such as this one.
http://www.laughingplace.com/News-ID108300.asp
Great set of columns, by the way. I've always been a fan of how some of the disney technology was invented and implemented.
HAHAHAH! No one uses hands anymore to measure distance! How ARCANE!
We use feet.
A side note: in New Zealand (and possibly other Commonwealth countries - I haven't checked) they don't even refer to "English units". Their term is "Imperial units". Which tells you how long it's been since they made the switch...
The problem had nothing to do with eglish->metric conversion.
Also, there is nothing inherently better about the metric system of measurement, vs. the english system of measurement vs. any other standardized system of measurment. If something is measured at 1.5 inches or 38.1 mm, it's the exact same length. The only advantage is commonality and not having to do conversions (which is an advantage, I admit). But there is no inherent advantage as to how well one system can perform over the other.
A modern day witchhunt.
Some things that would be nice to standardize (but will probably not happen in my lifetime)
- imperial - metric
- Letter paper - A4
- Fahrenheit - Celcius
- AM/PM - 24 hr notation
- month/day/year - day/month/year
Anything I left out?
No. The meter is currently defined as the distance light travels in a vacuum in 1/299 792 458 of a second. (The definition has changed a couple of times as science has advanced to make the definition more precise.) The meter is based on the Earth's merideans (lines of longitude) - it is 1 / 10 millionth of one meridian.
"The legitimate powers of government extend only to such acts as are injurious to others." Thomas Jefferson.
I don't think the average slashdot reader is going to get near enough to a girl to find out!
This incident (although caused by a transition TO the metric system) leads us to the question how many more years until we finally get rid of the imperial system. The US standard bureau has a page that describes their effort in the conversion. They quote the metric conversion act of 1975, but i don't know how much has happened since then. How many years do I have to buy US stuff here in Europe that is half metric and half imperial? For god sake, even the UK has switched! Does anybody know a real time-table for the transition??
Obligatory Pulp Fiction quote:
If you ever run into a imperial system freak ask him to calculate how many square inch there are in a square mile
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
The problem has little/nothing to do with it being metric/imperial.
Someone ordered the wrong part. That's it.
This is why drawings should be controlled. Only current known valid drawings should be used for anything.
This problem is as basic as someone using patches for linux kernel 1.2.13 on a 2.6 series kernel
(And the right term for "metric" is "SI").
SI units are legal in the United States and have been for a very long time. The inch was set at precisely 25.4 mm _by definition_ in July 1959.
The additional units, such as inches, miles, quarts, pounds, etc. which I believe are all legally defined by reference to SI units, are officially and properly referred to as "U. S. Customary" units. They have, of course, a strong historical connection to English units.
Unofficially, "Metric" and "English" are the U. S. customary designations for "SI" and "U. S. Customary."
"How to Do Nothing," kids activities, back in print!
If the U.S. hates the french so much, they should dynamite the Statue of Liberty, because that was a gift from the french to the U.S.
It would serve the french and the americans right!
See how stupid all this french or american bashing is?
Grow up, people.
I don't know the meaning of the word 'don't' - J
for gods sake its Litre and Metre......
Kingdom of Loathing (www.kingdomofloathing.com) Addicted is me
Bzzzzt. Thanks for playing!
From boson.physics.sc.edu :
At the beginning of the eighteenth century, the Danish astronomer Ole Roemer (famous for making the first measurements that showed that the velocity of light is finite) devised a temperature scale of his own for use with the alcohol-in-glass thermometers that he constructed. His thermometers attracted the attention of Gabriel Fahrenheit (1686-1736), a manufacturer of meteorological instruments in the Netherlands. In 1708 Fahrenheit traveled to Copenhagen to meet Roemer and see his thermometers, which were based on two reference points. For one reference Roemer used a mixture of ice, water, and salt to reach the lowest temperatures then attainable in the laboratory, which he called zero. His other reference was the boiling point of water, which he arbitrarily designated as 60 degrees.
Fahrenheit returned home to make thermometers like Roemer's. In 1714 he overcame technical difficulties with alcohol thermometers by substituting mercury as the expanding liquid. The use of mercury extended the range of temperature measurements from well below Roemer's zero to well above the boiling point of water. Furthermore, mercury expanded and contracted more uniformly than the other liquids then in use. As a result, Fahrenheit could mark his mercury thermometers more accurately and with finer divisions.
By 1724 Fahrenheit had adopted a new scale, similar to Roemer's but with much finer divisions. For the zero point he chose the same reference as Roemer. However, since his thermometer was intended for meteorological observations, he wanted a second reference point that would be nearer the maximum observed temperature for weather. He chose the normal temperature of the human body as the upper reference point, which he called 96. Fahrenheit gave no reason for his choice of 96, but it may have been due to his desire for a finer scale and because 96 is evenly divisible by 2, 3, 4, 8, and 12.
Why didn't Fahrenheit choose the freezing point of water for his zero reference, as Newton had done before him and as Celsius did later on? Perhaps Fahrenheit was influenced by Roemer, or he may have wanted to avoid the inconvenience of repeatedly using negative temperatures during winter. Also, in the early 1700s it was widely believed that water did not always freeze at the same temperature. Soon, using his newly calibrated thermometers, Fahrenheit learned that water always froze at 32 on his scale. He immediately added this third reference point to his instruments.
Any sufficiently well-organized Government is indistinguishable from bullshit.
Is that the metric system is flawed. It is defined in terms of the size of 18th century railroad tie sizes, which is totally arbitrary.
Mmm-hmm. So, clearly, defining length in terms of the feet of a 1200-year old dead Frankish king is a better choice?
Don't give me that crap about how much better the US economy performs than the EU. The median standard of living in the EU is higher than in the US. The US economy is great at producing wealth at the top, but conservative Americans have an aversion to using the economy to solve social problems ("communism! class war!"). I think this is a major reason why Europeans view the US as "backwards". Yes, both the US and the EU have economies that have solved the problems of food, shelter, and medicine. But the US has not seen to distributing those solutions to the people.
Many Americans have an ingrained sense that the only job of the economy is to grow. Things like social nets and environmental protections interfere with the ability of the (total) economy to grow at the fastest rate possible, so they must be inherently bad. This is the unifying economic philosophy of the conservative Republicans: government itself is inherently bad precisely because it siphons money (taxes) away from investment and consumption. If you believe in Reaganomics ("a rising tide lifts all boats") this makes some sense. But in the real world, it leads to a morally bankrupt society obsessed with money.
</rant>
So in conclusion, there are 36 inches in a yard.
Gates' Law: Every 18 months, the speed of software halves.
A friend of mine in college in the late 80's did an internship with Disney Imagineering. At the time, they were redrawing plans for several attractions that were to be copied almost exactly from California and Florida version for use in Euro Disney. There was great concern that the Imperial to metric round-off would be a problem. The contractor's union in France mandated that they only use metric units in the blueprints, which is reasonable. But if you're trying to duplicate a ride that was originally designed in Imperial units, you need to keep in mind quite a few significant digits when you're measuring. For example, a section of track in a given ride might be 10 feet in the US. In metric that's 3.048 m. Would the French contractors really measure to that precision? Or would they round off to 3.05 or event 3.0? They were concerned that roundoff might be systematic causing the errors to accumulate in one direction. This was a big concern, and there were debates over whether some rides needed to be redesigned in metric from the start and possibly give up economies of standardized parts.
That this happened in Space Mountain is also interesting, because Space Mountain was the first rollercoaster to have ATIS (automated track inspection system). Since it was a tightly wound coaster in a confined space it was difficult to do visual inspections. ATIS uses two techniques to detect problems with the track. The rails are actually tubes and they're pressurized in sections. When small cracks start to develop, the pressure drop is detected. Sensors also time cars through different sections of the track. If there is a trend of cars slowing through a section over time, it indicates that the ties between the rails are starting to give. ATIS is so much better than visual inspections at detecting problems early that it's used on most modern roller coasters.
Hello, I live in Montreal, Canada. Here we use three different systems; officialy, we use the metric system, for example: - road signs and cars are in kilometers - the pumps calculate gas in liters - outside temperature is indicated in Celcius by the medias - only the metric system is shown in school But, we also use the imperial system, which is the system of the English empire that we used previously (Canada is part of the Commonwealth as being one of the oldest english colonies). For example, lots of my uncles and aunts (I'm 25) will talk to you about their cars doing miles per gallon, miles per hour, etc. They will also buy stuff at the store in pounds. I personnaly weight myself in pounds and mesure myself in feet. That is not close to change... even if then babies are weighted in kilos at the hospital, and measured in centimeters, they also indicate the conversion on the official papers, otherwise the parents don't have a clue. Also, I personnaly have trouble reading the inside temperature in Celsius... I know exactly how warn I like it, but it's in Farenheits... (even if we only calculate the outside temperature in Celsius, and nobody converts them to understand, not even my grandfather). Also, I have never seen someone calculate the temperature of the pool or spa in Celsius... Don't ask me if 25 Celsius is hot or cold for a pool, I really don't know ! And finally, we also use the American system. The american system is different that the imperial for some measures like "gallons". For example, an imperial gallon is almost exactly 4 liters, while an american gallon is 3.78 gallons... this is why it's always frustrating when you put windshield washer fluid in your car, and they sell you the fluid in 4 liters containers, but the damn US car's ww fluid container is only 3.78 liters ! You always have to carry the damn container because they is always some left... Also, all the contruction is done in feet and inches. We produce the materials, lots of them, but none of it is produced in meters, because the main market is the US, so they just don't bother with our small market and produce everything in feet. This means that architects and engineers, even if they only learn the metric in school, must learn the english and american systems when in university. The same applies for a lot of people that do plumbing, mecanics, and even furniture. However, the people here always use the same terms as before, even if the units have changed; for example, we will say "a pint of milk", even if nore it's no more a pint, but it's a liter... Which system I prefer ? Well, I don't really care... I find the metric system the best, but I would certaintly have problem purchasing furniture in centimeters when all my house as been constructed in feet. I do like the feet and inches, because I find them conveniently easy to estimates, but when you start evaluating distances that are longer than the terrain my house is built on, I will say "300 meters further, turn left"... and will calculate in kilometers. The thing is, if the damn US could convert to the same thing as the rest of the world (which will never happen, or perhaps never before China is the new superpower), we will be stuck with the three systems in Canada...
Seriously. Metric is base 10, Imperial units are base 12.
Some of them are, some of them are not.
1 pound = 16 oz
1 stone = 14 pounds
1 foot = 12 inches
1 yard = 3 feet
1 US pint = 16 US fl oz
1 UK pint = 20 UK fl oz
1 Gallon = 1 pint
You're deluded if you think this mess has any value beyond familiarity (and, being unfamiliar with it, I had to look up all those conversions with Google Calculator...)
Maybe you'd like to go back to Imperial coinage too? 12 pennies to the shilling, 20 shillings to the pound, two shillings to the florin, 2 shillings and sixpence to the half crown...
I can live with people insisting on using Imperial measures.
What bugs me is when they then only halfway use the Imperial paradigm.
Case in point: when the iPod Mini was announced, I went to the web page to check out the specs. 2" x 3.6". Not having any intuitive feel for what that might mean, I wandered around the office trying to borrow a ruler, and once I'd found one, started to draw an iPod-sized square on a piece of scrap paper.
A 2" line across the bottom was easy. Then I set about drawing the vertical. 3", then another 6 gradations... oh, wait a minute, each inch is subdivided into 16ths. Tricky. Grab calculator.
So please, either use mm, or go the whole hog and state 3 inches and (10/16)".