The Link Between a Horse's Arse and the Space Shuttle

  • Thread starter Art
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  • #1
Art

Main Question or Discussion Point

An amusing story I came across :biggrin:
We've Always Done It That Way!

Does the statement, "We've always done it that way" ring any bells? The
US standard railroad gauge (distance between the rails) is 4 feet, 8.5
inches.

That is an exceedingly odd number. Why was that gauge used? Because
that's the way they built them in England, and English expatriates built
the US Railroads.

Why did the English build them like that? Because the first rail lines
were built by the same people who built the pre-railroad tramways, and
that's the gauge they used.

Why did "they" use that gauge then? Because the people who built the
tramways used the same jigs and tools that they used for building
wagons, which used that wheel spacing.

Okay! Why did the wagons have that particular odd wheel spacing? Well,
if they tried to use any other spacing, the wagon wheels would break on
some of the old, long distance roads in England, because that's the
spacing of the wheel ruts.

So, who built those old rutted roads? Imperial Rome built the first long
distance roads in Europe (and England) for their legions. The roads have
been used ever since. And the ruts in the roads? Roman war chariots
formed the initial ruts, which everyone else had to match for fear of
destroying their wagon wheels. Since the chariots were made for imperial
Rome, they were all alike in the matter of wheel spacing.

The United States standard railroad gauge of 4'-8.5" is derived from the
original specifications for an Imperial Rome war chariot. And
Bureaucracies live forever.

So the next time you are handed a specification and wonder what horse's
arse came up with it, you may be exactly right, because the Imperial
Roman war chariots were made just wide enough to accommodate the back
ends of two war horses.

Now the twist to the story...when you see a Space Shuttle sitting on its
launch pad, there are two big booster rockets attached to the sides of
the main fuel tank. These are solid rocket boosters, or SRBs.

The SRBs are made by Thikol at their factory in Utah. The engineers who
designed SRBs would have preferred to make them a bit fatter to carry a
bigger fuel payload, but the SRBs had to be shipped by train from the
factory to the launch site. The railroad line from the factory happens
to run through a tunnel in the mountains. The SRBs had to fit through
that tunnel. The tunnel is slightly wider than the railroad track, and
the railroad track, as you now know, is about as wide as two horses's
behinds.

So, a major Space Shuttle design feature of what is arguably the world's
most advanced transportation system was determined over two thousand
years ago by the width of a horse's arse.

And you thought being a horse's arse wasn't important!
 

Answers and Replies

  • #2
russ_watters
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There is nothing wrong with that line of logic for the American railway system. You work with what you have.
 
  • #3
J77
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Nice story :biggrin:
 
  • #6
brewnog
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I had always liked that story, and always suspected that a good proportion of it was cobblers, so when I visited the ancient Roman cities of Pompei and Herculaneum I made a point of looking at the ruts in the roads.

Sure enough, the ruts were mostly somewhere between 4'6" and 5'. Not really so surprising when you think about it.
 
  • #7
Art
I had always liked that story, and always suspected that a good proportion of it was cobblers, so when I visited the ancient Roman cities of Pompei and Herculaneum I made a point of looking at the ruts in the roads.

Sure enough, the ruts were mostly somewhere between 4'6" and 5'. Not really so surprising when you think about it.
Ah so there could be some truth in it afterall?? :smile:
 
  • #8
Astronuc
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Most railroad historians are aware of the fact that the Erie Railway was originally built to six-foot gauge, . . .
The rationale was to keep competitors out.
http://www.nrhs.com/spot/erie/ [Broken]

According to the Encyclopedia of American Business History and Biography, at the beginning of the Civil War, there were more than 20 different gauges ranging from 3 to 6 feet, although the 4-foot, eight-and-a-half inch was the most widely used. During the war, any supplies transported by rail had to be transferred by hand whenever a car on one gauge encountered track of another gauge and more than 4,000 miles of new track was laid during the war to standardize the process. Later, Congress decreed that the 4-foot, eight-and-a-half inch standard would be used for transcontinental railway.
3' 6" is considered narrow gauge, and there were isolated RRs that kept it, e.g. the line between Silverton and Durango.

http://en.wikipedia.org/wiki/Railway_gauge

Some lines were something like 5' or 5' 6", and from what I recall (which could be legend), is that a particular gauge depended on the nationality of the chief engineer, with British, Irish, Scottish or Americans having different preferences. That might be actually true in isolated cases.
 
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  • #9
BobG
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The story is fiction, but that isn't what bothers me. The tone implies that it's silly to base decisions just upon "We've always done it this way". A standard size of railroad is a poor example.

An example of why "We've always done it this way" is sometimes a good idea is VCRs. Some people can remember when there were two different types of VCRs with two different sizes and formats for tapes (i.e. - some people can remember when "we didn't always do it this way"). Once you'd bought one type of VCR, you were pretty much committed to always buying that type of VCR since, eventually, your tape library would be too large to just write off. Could you even imagine marrying someone who used Beta when you used VHS? You'd have to be a two VCR family because neither of you could give up your tape library.

Sometimes, having choices just makes life more complicated. There needs to be some standardization. If you didn't make railroads the same size, transportation via railroad would be a lot more expensive since cargo would have to be loaded off of one train and loaded onto a different train every time the size of the railroad changed.

The story's amusing, but they should have at least found an example where doing things the same way didn't make sense. Using 'QWERTY' keyboards instead of Dvorak keyboards, for instance. There's a story that illustrates how bizarre a path decisions can be.
 
  • #10
Art
The story is fiction, but that isn't what bothers me. The tone implies that it's silly to base decisions just upon "We've always done it this way". A standard size of railroad is a poor example.

An example of why "We've always done it this way" is sometimes a good idea is VCRs. Some people can remember when there were two different types of VCRs with two different sizes and formats for tapes (i.e. - some people can remember when "we didn't always do it this way"). Once you'd bought one type of VCR, you were pretty much committed to always buying that type of VCR since, eventually, your tape library would be too large to just write off. Could you even imagine marrying someone who used Beta when you used VHS? You'd have to be a two VCR family because neither of you could give up your tape library.

Sometimes, having choices just makes life more complicated. There needs to be some standardization. If you didn't make railroads the same size, transportation via railroad would be a lot more expensive since cargo would have to be loaded off of one train and loaded onto a different train every time the size of the railroad changed.

The story's amusing, but they should have at least found an example where doing things the same way didn't make sense. Using 'QWERTY' keyboards instead of Dvorak keyboards, for instance. There's a story that illustrates how bizarre a path decisions can be.
I'm not sure but weren't there 3 VHS formats originally with Philips 2000 making up the triumvirate?

On the QWERTY keyboard, I read somewhere the keys were laid out in such a way as to try to stop people typing too fast to prevent the keys from jamming. When word processors came along it would have been too difficult to retrain typists and so they kept the same key configuration. Anybody else hear that or is there another reason?
 
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  • #11
Yup thats the reason I heard. THe Dvorak setup is better because it factors into account the most used letters and places each on a different finger.. (I am assuming a bit there, but I know its something along those lines)..

Qwerty keyboards were for typewriters, probably to ensure that the rods didn't tangle up or something.
 
  • #12
Astronuc
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Sometimes, having choices just makes life more complicated. There needs to be some standardization. If you didn't make railroads the same size, transportation via railroad would be a lot more expensive since cargo would have to be loaded off of one train and loaded onto a different train every time the size of the railroad changed.
Sometimes in a large organization or industry, one goes done a path far enough that there is no turning back - a lot of institutional inertia. I thought the Pentagon (military) was like that, and I've seen it nuclear and aerospace industries, and probably telecom and other large industries.

Fortunately there are standardization organizations, but even then, there are personal and institutional (again human) biases/prejudices.

And that's the way it is . . . Walter Cronkite :biggrin:
 
  • #13
Art
Sometimes in a large organization or industry, one goes done a path far enough that there is no turning back - a lot of institutional inertia. I thought the Pentagon (military) was like that, and I've seen it nuclear and aerospace industries, and probably telecom and other large industries.

Fortunately there are standardization organizations, but even then, there are personal and institutional (again human) biases/prejudices.

And that's the way it is . . . Walter Cronkite :biggrin:
There are different track gauges throughout europe but that was deliberate to protect against invasion by other states.
 
  • #14
Astronuc
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There are different track gauges throughout europe but that was deliberate to protect against invasion by other states.
Yeah, I've heard that. Is the EU now trying to standardize to some uniform gauge throughout Europe including eastern Europe? I would expect so, but I haven't been following the evolution of the EU as closely as I'd like.
 
  • #15
BobG
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I'm not sure but weren't there 3 VHS formats originally with Philips 2000 making up the triumvirate?

On the QWERTY keyboard, I read somewhere the keys were laid out in such a way as to try to stop people typing too fast to prevent the keys from jamming. When word processors came along it would have been too difficult to retrain typists and so they kept the same key configuration. Anybody else hear that or is there another reason?
The keyboard was designed around 15 years before the first touch typist, so the idea that the keyboard was designed to slow down touch typists might be a myth. The keyboard was designed with fast two-finger typists in mind.

Trying to minimize key jams was one of the primary reasons for the QWERTY layout. Theoretically, the further away two successive keys were, the less the chance of jamming. The angle would minimize the amount of time the two keys would occupy overlapping space. Sholes (the designer or the QWERTY keyboard) hired someone to do a statistical analysis of which letters were most commonly typed in succession and layed out his keyboard from that. In practice, the overlapping space barely made a difference.

Having successive keys far apart had a more important effect. In an era when touch typing was virtually non-existant, alternating hands for successive keys made faster two finger typists. Even with touch typing using all fingers, it's egonomically more efficient to type successive keys with alternate hands. So, QWERTY had a physical advantage over rival keyboard layouts and is a decent design - just not the best.

Dvorak keyboards are better at keeping the majority of letters on the home row and at balancing the load between hands - just slightly more letters typed with the right hand, which also happens to the dominant hand for most people. QWERTY has a more unbalanced load, with most letters typed with the non-dominant hand. Dvorak doesn't do as good a job as QWERTY with successive keys being typed by alternate hands.

Dvorak is more efficient than QWERTY, but not enough overcome the inertia of QWERTY keyboards - especially since the primary advantage of Dvorak keyboards for most typists is reduced fatigue, not increased speed (however, the world record for speed, 150 wpm for 50 minutes, was accomplished on a Dvorak keyboard).

Stories exagerrate the difference between Dvorak and QWERTY keyboards, but it is a valid example where 'good' is good enough just because everyone does it that way.

The bizarreness is in the stories that pop up explaining why a superior technology never got a foothold. Probably most have at least a hint of truth. For example, one popular story had the Navy testing the difference between Dvorak and QWERTY keyboards at the beginning of WWII and finding Dvorak keyboards were superior, but having to scrap their plan to train an army of Dvorak keyboards because the Navy had already purchased some enormous number of standard typewriters. The Navy did test the difference between Dvorak and QWERTY keyboards, but towards the end of WWII, not the beginning. Dvorak keyboards did do better in the tests, but custom made typewriters probably would have been more expensive than purchasing standard keyboards, so the Dvorak keyboards would have had to knock the snot out QWERTY keyboards to really win the contest.

Some technologies wind up having stair step evolution instead of steady evolution just because of the advantages of standardization. Some threshhold has to be passed before the newer technology is worth scrapping past investments. Huge vinyl record collections didn't stop the compact disc from becoming popular and VHS movie collections didn't stop DVD's from becoming popular. On the other hand, a tiny improvement over CD's won't entice people to scrap the CD collection for a newer technology only slightly better.
 
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