Commentary: Metric Mayhem
Practically the entire world uses the metric system. Is it time for the United States to follow suit?
- By Michael Milstein
- Air & Space magazine, March 2001
Not long ago, I was writing a story for this very magazine about the delicate extraterrestrial dance of a U.S. spacecraft around a potato-shaped asteroid named Eros (see “Hang a Right at Jupiter,” Dec. 2000/Jan. 2001). The simplicity of the spacecraft’s course stood out in a universe that is rarely simple and convenient: The boxy craft would circle 100 kilometers from the asteroid’s cratered surface, then fire its engines to drop into an orbit 50 kilometers above the tumbling space rock.
Finally, I thought, I don’t have to worry about how to round off some impossibly large number such as the speed of light (299,792.458 kilometers per second) or the distance between Earth and the sun (149,597,870 kilometers).
At least that’s what I thought until the editors got hold of the story and reminded me that this magazine does not use metric units. Convert all kilometers to miles, they said, all meters to feet, and all kilograms to pounds.
Why not use metric, I asked. All the scientists working on the spacecraft use metric. All their written materials use metric. Every other country that operates in space uses metric. Their reply: Because we have always done it the other way. It’s what our readers understand. It’s the American Way.
Lengthy investigation suggests that this is about the only explanation for why the United States as a whole evades the metric system while most of the rest of the world embraces it—because we have always done it the other way. We’re like a crotchety old hermit. The rest of the international neighborhood works together and speaks the same language while we huddle in a dark, outdated house at the end of the street (which we share with Liberia and Burma, the only other two nations that have not gone metric), mumbling our own inscrutable tongue of inches, feet, yards, miles, links, rods, furlongs, pecks, bushels, bolts, barrels, fathoms, leagues, acres, ounces, pounds, tons, cups, bales, pints, tablespoons, gallons, hands, chains—most of which have no logical relationship to one another—and all the other aged terms of what is often called the Imperial, or English, system but which metric advocates derisively refer to as FFU (Fred Flintstone Units). So I could have probably said to my editor, “That’s typical FFU.”
But of course I didn’t.
Such lack of backbone may be why the U.S. portion of the International Space Station is built in Imperial Units while the rest of the super-expensive structure has been constructed in metric. About 10 years ago NASA gave serious thought to the idea of building the whole thing in metric, but decided that would drive the cost way up. All the NASA contractors were tooled to build parts in inches and pounds; converting to metric would have required revised designs and new machines. So instead they developed an elaborate and costly computer-modeling and cross-checking procedure to make sure that metric and Imperial parts fit together and work properly.
Of course, an all-out metric conversion would carry costs of its own. No one has ever solidly estimated it, just as no one has estimated the loss of U.S. trade dollars due to the unwillingness of other nations to take shipments in pounds and gallons. Certainly we would need to recalibrate scales, gas pumps, and the like. There’s always a cost to repairing a sinking ship, but the cost of not repairing it may be far greater.
Comments (13)
Why yes! How logical...
In aerial navigation it's so much simpler to recognize that one degree of longitude is 1.852 kilometers instead of 1 nautical mile.
Makes calculations a lot easier, too...
Posted by Dan Marotta on July 2,2008 | 11:20 AM
The vast majority of Americans are resigned to the fact that we should have been metric a long time. I had discused this issue with tens of thousand people from all walks of life.
Many Americans are ashamed to talk about this issue because they know that the U.S. has spent billions of dollars for over a century and half repeatedly trying to go metric and failing every time. I am ashamed also.
The lack of leadership is the only reason we have not phased in metric as every nation of this earth has done or is in process of implementing.
Posted by Stan Jakuba on May 31,2009 | 08:48 PM
One degree of longitude is not one Nautical mile, One Nautical mile is 6076.11549 international feet as opposed to the Survey feet used for measuring land in the US. It's approximately one Nautical mile but not exactly and what use is that in Space? The metric system is way simpler, its integrated, you can do most calculations by moving the decimal point.
Posted by Michael Payne on July 18,2009 | 08:10 PM
Michael Payne is right.
Let's also mention that one cube decimeter of water (exactly equal to 1 liter) weights about 1 kilogram (the exact number being 0.999785 kilograms).
So yes, the metric system is far more powerful than FFU!
P.S.: Love the alternate name for US customary units.
Posted by Chris on March 4,2011 | 05:24 AM
As a Senior Technical Communications Specialist of decades of practice, I find it frustrating in the extreme that the US continues to wield its 'ugly American' club regarding the matter of standard measures. At some point, the US will find itself told by the rest of the world either to shape up or do without international trade.
I was raised on the FFU system. When I entered military service, I was astounded at how easily I learned and accepted SI units. Everything just made so much sense. Multiples of ten, yea!
The foot-dragging industrialists who do not want to convert their machines are doing themselves and the nation a huge disservice. It's simple, folks. When a FFU machine wears out, replace it with a metric one. The costs of such machines have come way down, while the costs of FFU machines continue to rise as fewer and fewer companies make them. NASA's assertion that it is too costly to use SI as the basis for measure for space hardware is bogus. It presumes that the rest of the world must bow down before our wisdom.
As for what 'the people' want or expect, that always has been the huge bolder thrown in the way of progress. It never has been a valid argument. However, the Luddites in our society continue to try to convinced us that it is one. For some good bitter laughs, read the Wikipedia article about Luddites.
Perpetuating the concept that it would be a disservice to the US to convert to SI is no longer defensible, and has not been for the last 50 years. As far as I can see, the only country that had a legitimate call for keeping the FFU systems going was Great Britain and its associated colonial children. The basis of their financial system was the Pound Sterling. However, even that now has fallen into disuse with the acceptance of membership in the ECU and its Euro, which is decimal-based.
Clearly, it is long past time for the US to wake up and join the rest of the world. Write your congress-person and demand it.
Posted by John Fairbairn on April 8,2011 | 12:21 PM
May I propose PPU as miles etc. were dumped on the British by the Romans (e.g. Pontius Pilate)? The British in turn dumped them on the colonies. What was the point of winning the war of independence if not to throw off the dumb units imposed by the invaders?
Posted by Mike Oxley on January 30,2012 | 05:14 PM
I wonder if people resistant to adopting metric units in everyday life realize that American money uses the decimal system. Golly! 10 pennies=1 dime and 10 dimes=1 dollar. Much more rational to exchange dollars for say shillings, farthings, and pounds.
Posted by J.MacMillan on February 5,2012 | 11:00 PM
The UK decimalised the pound sterling on the 15th February 1971. Shillings & farthings etc. are no more.
Posted by Mike Oxley on February 8,2012 | 06:16 AM
I think the author got the conversion wrong on the asteroid's orbit distances. '100 km' / '50 km' have only one significant digit, they're basically rounded numbers. So a translation (that is different from a conversion, folks!) to US units, for the magazine readers' benefit, would give '60 miles' / '30 miles' in rounded distances.
Similarly, the 'Indy 500' would be the 'Indy 800' in metric, and '20,000 Leagues Under the Sea' would be '100,000 Kilometers Under the Sea'. (Ever notice how deep that would be? To the bottom of the ocean, then through the earth and then into space, more than a quarter the distance to the moon!)
Posted by Maarten Jansonius on February 24,2012 | 11:14 AM
Where I work we have machines that are part SI and part FFU. So we have to have two sets of tools anyway. I have two sets of tools at home. Shouldn't be hard to start making all machines and their fittings SI as most people probably already have the tools.
Burma is really funny. There are no speed limits so they don't have to worry about mph, but their cars are all imported from Japan and made to drive in kph on the left side of the road. They drive on the right side anyway (just to thumb their noses at the British?) so all the vehicles have to have left-side mirrors on the front bumper so the drivers (sitting on the right) can see who's coming up beside them on the left.
Posted by Mr. Buck on March 13,2012 | 09:24 PM
Working as an engineer in EU in the offshore industry with clients from the US, I often get stunned with some of the units actually in use e.g. short tonnes, kips, gpm. Seems to be all customs, no logic; which leaves you to convert units until you way an ounce.
One thing about usage of units in Europe, it is not all decimal i.e. for time we not only use seconds but also hours, minutes and days. Nobody expresses the speed of their vehicle in m/s but use km/hr instead.
When using those units we get reminded how convienent decimal system is.
@ Maarten Jansonius '100 km' has 3 significant figures i.e. '100 km' can be anywhere between 99.5 and 100.4 km/hr; not between 50 and 140 as you imply. Also 20.000 Leagues Under the Sea refers to the (mostly horizontal) distance travelled under sea, not the depth.
Posted by Marijn Hepp on March 14,2012 | 10:48 AM
I see people struggle with imperial measurements quite often but they say its American.I observed a mistake because the conversion is not precise enough.The benchmark was 1500mm simple enough they converted it to four feet eleven inches and one sixteenth which changed the dimension to 1500.188mm.
Reading metric is like counting money . I will continue to make money also because some people limit themselves by not learning metric.
You should know both to survive in this highly competitive industrial environment of today.
Posted by Michael Wells on February 10,2013 | 04:54 PM
Who completed the crowning achievement of space exploration and what system did that agency use? Standing alone on top among 200 odd countries. Coincidence?
Who's fighting aerospace equipment knows no equal in the world? What system did we choose to build this on? Why do certain second-place lesser metric countries employ technology theft in their envy of this Imperially developed technology as their only hope of acquiring this knowledge. More coincidence?
Coincidence that NASA chose metric recently and simultaneously now is incapable of achieving the 1950s feat of putting a person in space.
Who exploded the modern digital era onto advanced civilization. Yeah.
When I hear Imperial-phobes scream "every other country...", I'm hearing you say "The Congo, and Somalia use metric for their scientific contributions to the world!! What's wrong with us???"
If you put metric speed limit signs on an American highway, 90% of people will either not accurately understand the value or will waste time converting, therefore by added effort it is technically the more difficult. Same with temperature, weight... you name it.
Why are some so arrogant to impose a foreign system that will not only fail to return measurable results, would cost billions to implement, and eliminate clarity in basic operations for decades. I don't wish to impose our system on lesser countries. It's their business. And stay out of mine - we were doing fine.
If you find little conversion nuisances too overwhelming in your field, may I recommend a future as a cashier? There's a nice little market in Mogadishu I hear is hiring.
Posted by T. S. Radmanovich on April 10,2013 | 07:09 PM