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NASA Sticking To Imperial Units For Shuttle Replacement
JerryQ sends in a story at New Scientist about the criticism NASA is taking for deciding to use Imperial units in the development of the Constellation program, their project to replace the space shuttle. "The sticking point is that Ares is a shuttle-derived design — it uses solid rocket boosters whose dimensions and technology are based on those currently strapped to either side of the shuttle's giant liquid fuel tank. And the shuttle's 30-year-old specifications, design drawings and software are rooted in pounds and feet rather than newtons and meters. ... NASA recently calculated that converting the relevant drawings, software and documentation to the 'International System' of units (SI) would cost a total of $370 million — almost half the cost of a 2009 shuttle launch, which costs a total of $759 million. 'We found the cost of converting to SI would exceed what we can afford,' says [NASA spokesman Grey Hautaluoma]."
I work for an engineering company, and unit conversions are not a trivial operation. All of our drawings are created in autocad, and after several years it becomes difficult if not impossible to find the original file. As such, converting achieved documents requires recreating the document entirely from scratch. We also use a fairly vigorous quality control system that requires 3 engineers to check every document change, verify the calculation, and repeat the calculation using a different method to ensure that no mistakes were made.
We recently acquired an older project where we needed to simply change the title block on each page, and this process took roughly 5000 hours. For something on the scale of the space shuttle, 370 million isn't unheard of.
Claim: The United States standard railroad gauge derives from the original specification for an Imperial Roman war chariot.
Status: False
XML is a known as a key material required to create SMD: Software of Mass Destruction
I'm from the UK, and my mental image of measurements is fucked.
I know how much a pint is. I know how much 1kg is, but I don't know how much is 1 pound in weight. I know how tall I am in feet and inches, but not in meters.
All because we use metric for some reasons, and we are still stuck in imperial for others. My milk comes in bottles that are labelled 568ml although *everyone* refers to it as a pint, obviously our alcoholic drinks come in pints and half pints. Our speed limits are measured in miles per hour, yet we used to run the 100 meters at school. My height has always been given to me in feet and inches (while growing up by my parents) and if you speak to pretty much anyone they will also give their height in feet and inches, yet if I go to the doctor, they want me to know how high in meters. If you go under a low bridge, the height is given in feet.
When I go swimming the pool is in meters, when referring to medium distances anyone aged over 40 refers to yards, everyone below that refers to meters, at larger distances it's rare for anyone to use kilometers. Anyone over 40ish only understands Fahrenheit, everyone below uses degrees centigrade.
Generally speaking things are moving to metric (thankfully) but it will take many many years for imperial to die here currently we are in one big measurement mess and we will be for some time, especially as every traffic sign is in imperial.
You don't seem to understand, even a little. These numbers are on a piece of paper that no longer exists on a computer. Not even the most advanced computer script in the world can adjust paper. So okay, I understand part of your point, put it into the computer first, and then run the script. These documents are crawling with numbers. Line numbers, electrical classifications, instrument identifiers. Even if I had a script to manage the process, you then have the problem of units. I'm not doing 5000 ft to meter conversions. We have lengths (using both ft, in, ',and "), weights, volumes, temperatures, powers (hp, MMBtu/hr, kW, MW) and so forth. Even if you could have a script smart enough to check for units, how would it tell the difference between a temperature and a temperature change? If I have a heat exchanger with a temperature change of 50ÂF, the correct metric temperature change is 27.8ÂC. If you got 10ÂC, you used the wrong method. The sheer amount of back checking I would have to do to make sure a rogue script didn't destroy my drawings would be insane.
This is not a simple database you're playing with.