Category Archives: Metrication

Lost In Metric Non-Conversion

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Cargo-Plane

By The Metric Maven

Isaac Asimov once wrote an interesting essay called Lost in Non-Translation. I don’t recall its details, other than he pointed out the considerable confusion caused by the difficulties that occur with translations from one language to another.

Our translation tale begins when I serendipitously ran across a small article in an old issue of the USMA’s Metric Today (July-August 2001 Vol. 36 No. 4 page 8) . I was surprised I’d never heard about this incident:

MT-Article

Eight people were killed and over 40 injured?—and this incident seems lost to metric history? The KE6316 event happened only about four months before the famous loss of the Mars Climate Orbiter that September—and the first metric incident, KE6316, that cost human lives, went comparatively unnoticed? This gobsmacked me. I immediately turned to Wikipedia and the flight mishap was listed. Here is what it has to say:

  • 15 April 1999 – Korean Air Cargo Flight 6316 (McDonnell Douglas MD-11) from Shanghai to Seoul took off despite the Korean co-pilot’s repeated misunderstanding and miscommunication with the tower and the pilot. The aircraft climbed to 4,500 feet and the captain, after receiving two wrong affirmative answers from the first officer that the required altitude should be 1,500 feet, thought that the aircraft was 3,000 feet too high. The captain then pushed the control column abruptly forward causing the aircraft to start a rapid descent. Neither was able to recover from the dive. The airplane plummeted into an industrial development zone 10 kilometers (6.2 mi) southwest of Shanghai Hongqiao International Airport. The plane plunged to the ground, hitting housing for migrant workers and exploded. Damage: Destroyed Injuries: 37 on ground Deaths: 8 (all 3 crew and 5 on ground) Airframe: Written Off[22]

When I read this account, I was floored to see that the metric-medieval unit confusion, which was at the root of the incident, was not included in the Wikipedia description of the accident. What on Earth? The article has a reference. Perhaps the reference is at fault? Let’s see what it has to say:

MD-11F cargo plane HL7373 was operating flight KE6316 from Shanghai’s Honqiao Airport to Seoul. The plane was  loaded with 68 tons of cargo and pushed back from it’s stand. Shanghai Tower then cleared the flight as follows: “Korean Air six three one six clear to destination flight planned route flight level two niner zero. After departure turn left direct to November Hotel Whiskey. Initially climb and maintain niner hundred meters. Departure frequency one one niner zero five. Squawk six three one six.” The engines were started and the airplane taxied to runway 18. Shortly after 4pm the flight was cleared for takeoff. After takeoff the first officer contacted Shanghai Departure and received clearance to climb to 1500 metres (4900 feet): “Korean Air six three one six now turn left direct to November Hotel Whiskey climb and maintain one thousand five hundred meters.”


When the aircraft climbed to 4500 feet in the corridor, the captain, after receiving two wrong affirmative answers from the first officer that the required altitude should be 1500 feet, thought that the aircraft was 3000 feet too high. The captain then pushed the control column abruptly and roughly forward causing the MD-11 to enter a rapid descent. Both crew members tried to recover from the dive, but were unable. The airplane crashed into an industrial development zone 10 kilometers (6 miles) southwest of Hongqiao airport. The plane plunged to the ground, plowing into housing for migrant workers and exploded.

There it is in the reference, Shanghai told them to ascend to 1500 meters and then maintain that altitude. The actual quotation is given. The first officer twice thought that the authorized altitude was 1500 feet despite the fact that initial altitude value of 900, and the second, 1500, were both given in meters. The captain immediately decreased the altitude, and went into a dive from which they could not recover and crashed into a construction area.

I doubt the author of the Wikipedia summary had any malice, or intentionally obscured the the fact that the root cause of this crash was a confusion between metric and antique measures. At least I hope this is the case. The first paragraph of the reference material quoted above is in meters and the second changed to feet without directly pointing out the metric-Ye Olde English confusion. It can easily be inferred with a careful reading. The Wikipedia article condensed the first paragraph of the reference prose into a single sentence and buried the source of altitude confusion, but left most of the second paragraph intact.

What I do think is that measurement itself is so out of the minds of most people in the US, that they will convert to Ye Olde English exclusively, and thoughtlessly bury the lede six feet under. All one reads in the Wikipedia account is there was confusion about the altitude in the cockpit, but not its root cause, which was a confusion between Ye Olde English units and metric. In the case of the DART incident, the metric-medieval conversion error was obscured by NASA by burying it within a tome of a report. Here are two catastrophic failures, DART and Korean Airlines KE6316, which are independent of the Mars Climate Orbiter debacle, that have been lost to metric history. Both incidents demonstrate that measurements matter.

If you liked this essay and wish to support the work of The Metric Maven, please visit his Patreon Page and contribute. Also purchase his books about the metric system:

The first book is titled: Our Crumbling Invisible Infrastructure. It is a succinct set of essays  that explain why the absence of the metric system in the US is detrimental to our personal heath and our economy. These essays are separately available for free on my website,  but the book has them all in one place in print. The book may be purchased from Amazon here.


The second book is titled The Dimensions of the Cosmos. It takes the metric prefixes from yotta to Yocto and uses each metric prefix to describe a metric world. The book has a considerable number of color images to compliment the prose. It has been receiving good reviews. I think would be a great reference for US science teachers. It has a considerable number of scientific factoids and anecdotes that I believe would be of considerable educational use. It is available from Amazon here.


The third book is called Death By A Thousand Cuts, A Secret History of the Metric System in The United States. This monograph explains how we have been unable to legally deal with weights and measures in the United States from George Washington, to our current day. This book is also available on Amazon here.

Child’s Play

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By The Metric Maven

Bulldog Edition

Recently I was visiting Albuquerque New Mexico. While there, I went to the National Museum of Nuclear Science. It was an interesting enough experience, but it was the gift store that made the largest impact. On the back wall was a number of educational laminated exercise sheets. They are about 440 mm x 305 mm in size. The first to catch my attention was a sheet intended to “educate” young people about U.S. weights and measures. The U.S. weights and measures sheet seemed very simplified, and is reproduced below:

The typeface is large and legible, about 10 mm or so in height. There is plenty of space between the lines of text and the graphic design is very open and accessible.

When I found the metric version of this “educational resource” I was aghast. The typeface is reduced to about 5 millimeters in height, and the graphic design is cluttered. Clearly when one looks at this metric presentation, and compares it with the U.S. version, the metric version is just so complicated that only a Nobel Prize winner could understand it. The message is clear, U.S. Ye Olde English is simple, the metric system is complicated. The metric version is reproduced below for comparison:

The U.S. version has no metric equivalents on it. The metric version has Ye Old English equivalents on it. This is the first source of clutter. The second source of clutter is the prefix cluster around unity. The length section has millimeters, centimeters, decimeters, dekameters, hectometers and Kilometers. The same set of prefixes is used for the liter and the gram, with Ye Olde English equivalents added.

In my essay Naughtin and 1929, I wrote about a newspaper that was introducing the metric system that year and made it appear much more complex than needed. What was done there seems like a peccadillo compared with this group of Mormons making coffee. We are treated to a history lesson  that explains: “The Metric System was first proposed in France in 1670 by Gabriel Mouton. It is a system based on mathematics and not the size of a king’s body part.” No, the system part of the metric system was proposed by John Wilkins in 1668. It relies on scientific phenomena as a basis, and simplicity in expression. It is pointed out that the U.S. is “the only major country in the world not to adopt it.”

This product is called a Painless Learning Placemat, and has a 2014 copyright, so it is not a relic from the 1970s, it is contemporary obfuscation. At the bottom of each placemat is “Made in U.S.A.” The Ye Olde English measures placemat does not have the center section taken up with a history of measurement, and the SI prefixes with the prefix cluster around unity added. It does have SI Punctuation Rules. Rule #2 is not to use plurals on the unit symbols, so it’s: “hg not hgs.” One would not want to get their hectograms in a bunch. Rule #3 is there are no periods after units, it’s: “cg not cg.”, so make sure you have your centigrams without periods, as you will also be using lots of centigrams in your new fantasy metric world.

I will give the author(s) some credit for the other rules—mostly. Rule #1 is to leave a space between a numerical value and its metric symbol. They have 5 g not 5g. Rule #4 is to use a space instead of a comma for large numbers. However, the space they use in their example is so small that a young person (or the instructor) might be confused that a space exists. The kerning is awful:

Perhaps 10 000 and 10,000 might have been a better example?

Rule #5 advocates a leading zero on decimals. Their example is 0.6 mm not .6 mm. This is good, but when possible in a list of presented values, whole numbers are most expressive. 600 μm is succinct and this possible choice should be explained.

The reverse side of this placemat has “metric exercises” for the young person. They mostly involve the prefix cluster around unity, and therefore are for “practical” everyday use:

There are many more exercises in futility on the back side of the placemat. One is to “Draw a line from the prefix  to its correct numerical value.” These include mm, cm, dm, dk, hm, km with 10, 0.01, 0.1, 100, 0.001, 1000. One is then to take the prefix symbols and match them with the full prefix cluster. This includes mg, kg, dg, dkg, cg, hg, with dekagram, hectogram, milligram, kilogram, decigram and centigram. Those of you that are metric pedants will immediately notice that rather than using da for deca, this placemat has dk instead. It seems apparent to me, that when confronted with dkg, it’s possible for a young person to see it as a decikilogram. Well over 75-80% of the area of the backside of the metric placemat is taken up with the important task of understanding hecto, deca (sorry….deka), deci and centi. Metric is not better by 1000 on this placemat, it’s ten times worse. This “educational tool” is an unintentional argument for eliminating the prefix cluster around unity.

What young person would choose metric over Ye Olde English when they see nothing but complexity staring at them? The idea that more prefixes exist, such as Mega, Giga, micro, nano and so on, would certainly produce loathing for this complicated system, and budding American exceptionalism could possibly follow. The back side of the Ye Olde English placemat is far less dense, and tells you what you don’t have to remember:

The placemat does not mention Troy versus Avoirdupois pounds, even though silver and gold are weighed with Troy, and that seems fairly important. If a child understood the actual simplicity of the metric system, without the prefix cluster around unity, and was not conditioned with this misleading pre-metric placemat to see the U.S. weights and measures as simpler, they would revolt when they came across this set of exercises on the back side of the Ye Olde English placemat:

The metric placemat is so padded with worthless and pointless exercises, that it would probably convince the poor child that the Ye Olde English reverse side is easier than the back of the metric placemat. Considering the convoluted and misleading metric backside, it might actually be just about as bad—but of course it’s only typical of ignorance in action.

The U.S. placemat does not bother to relate any of the U.S. measurement units to metric units, but the metric placemat does—when it should not. In an actual adoption of the metric system, one changes to metric exclusively, and never looks back. The U.S. placemat has a small box explaining how to convert Fahrenheit to Celsius. On the U.S. back side, one is to parrot back this simple algorithm. The metric place mat has extensive exercises to convert a list of Celsius values to Fahrenheit and vice-versa.

What young person would not be repelled by the metric system when it’s presented in such an overly and artificially complicated manner? I’m glad I was never exposed to a “learning accessory” like this one when I was a child. It would have brought out my inner Chucky if I was faced with the choice. Whether I approach “science communicators” on The Skeptic’s Guide to the Universe, High School teachers, scientists, engineers, or other educators, there is a virtual eye roll, and a sanctimonious dismissal tinged with “I already know all about the metric system” or worse, the assertion that “it doesn’t matter what system of measure one uses.” I would like to think that most educators are interested in teaching and not simply parroting, but at this point it looks like “Polly want’s a hectometer.”

If you liked this essay and wish to support the work of The Metric Maven, please visit his Patreon Page and contribute. Also purchase his books about the metric system:

The first book is titled: Our Crumbling Invisible Infrastructure. It is a succinct set of essays  that explain why the absence of the metric system in the US is detrimental to our personal heath and our economy. These essays are separately available for free on my website,  but the book has them all in one place in print. The book may be purchased from Amazon here.


The second book is titled The Dimensions of the Cosmos. It takes the metric prefixes from yotta to Yocto and uses each metric prefix to describe a metric world. The book has a considerable number of color images to compliment the prose. It has been receiving good reviews. I think would be a great reference for US science teachers. It has a considerable number of scientific factoids and anecdotes that I believe would be of considerable educational use. It is available from Amazon here.


The third book is called Death By A Thousand Cuts, A Secret History of the Metric System in The United States. This monograph explains how we have been unable to legally deal with weights and measures in the United States from George Washington, to our current day. This book is also available on Amazon here.