Lost In Metric Non-Conversion

Cargo-PlaneBy 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-ArticleEight 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 1999Korean 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.