Origins of engineering specs Subject: Origins of engineering specs and government decisions. Ever wonder where engineering specifications come from? The US standard railroad gauge (distance between the rails) is 4 feet, 8.5 inches, an exceedingly odd number. Why was that gauge used? Because that's the way they built them in England, and the English built the first US railroads. Why did the English build them like that? Because the first rail lines were built by the people who built the pre-railroad tramways, and that is the gauge they used. Why did they use that particular gauge then? Because the people who built the tramways used the same jigs and tools that they used for building wagons, which used the same 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 the old, long distance roads in England, because that's the spacing of the wheel ruts in the granite sets. 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 (or by) Imperial Rome, they all had the same wheel spacing. The United States standard railroad gauge of 4 feet, 8.5 inches is derived from the specification for an Imperial Roman war chariot. Specifications and Bureaucracies live forever. The Imperial Roman war chariots were made just wide enough to accommodate the back ends of two war-horses. Now let's cut to the present... The Space Shuttle, sitting on its launch pad, has two booster rockets attached to the sides of the main fuel tank. These are solid rocket boosters, or SRBs. A company builds SRBs at its factory in Utah. The engineers who designed the SRBs wanted to make them a bit fatter, but the SRBs had to be shipped by train from the factory to the launch site. The railroad line from the factory has to run through a tunnel in the mountains. The SRBs had to fit through that tunnel, which is slightly wider than the railroad track, and the railroad track is about as wide as two horses' behinds. So.... a major design feature of what is arguably the world's most advanced transportation system was determined two thousand years ago by a horse's ass. Which is pretty much how most government decisions are made. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------