6 ms·

I wonder how many lives are lost each year (not just in aviation but globally) because the US refuses to convert to the metric system.

by eterm 8y ago

hn_throwaway_99 8y ago
Or spacecraft lost: https://en.m.wikipedia.org/wiki/Mars_Climate_Orbiter https://en.m.wikipedia.org/wiki/Mars_Climate_Orbiter
- rzimmerman 8y ago
  The loss of MCO is actually a very interesting story about both engineering culture (engineers noticed a problem but the organization didn’t respond to investigate/fix it) and the conversion to metric. The root came from NASA deciding to use metric on this project and a contractor using the wrong units. But it’s the kind of thing that the process should be able to catch and handle. It bugs me to dismiss this failure as “haha why doesn’t NASA use metric” because not only is it a direct result of NASA switching to metric, there are really good engineering lessons that get ignored.
microcolonel 8y ago
> I wonder how many lives are lost each year (not just in aviation but globally) because the US refuses to convert to the metric system. Keep in mind that the U.S. is not the only place where measures are mixed. If anything, British people end up using more measures than Americans. Here in Canada, we have a lot of things read out in both, because of the immense sticking power of customary measures. U.S. organizations are actively encouraged and (for the most part) fully allowed to adopt SI measures, but it's not like switching road sides, where everything makes sense after you hear "drive on the right now". Keep in mind that powered flight was basically entirely developed by Americans and pre-SI Brits, and already had more than fifty years of history by the time either pioneering country adopted SI in any significant way. It should not surprise you in the slightest that an American plane expected to hear fuel mass given as weight in pounds; in fact, it should astonish you that anyone is trying to measure it in kilograms in North America.
- eterm 8y ago
  I'm British, so you don't need to explain using mixed systems, however in any kind of academic, engineering or scientific contexts metric units are used almost exclusively. Yes, people still refer to height in feet and inches a lot, and we'll drink a pint (a real pint! None of your mini-pints!), but that does change over time. For example older people will use stone and pounds for their weight but being younger the doc doesn't bother telling me my weight in anything but kilograms so I don't even know my weight except in Kg. Even in Britain, in almost all engineering contexts, SI units would be assumed. Your point about Americans assuming imperial units is precisely wwhy it's so dangerous that metrification hasn't happened there. If the US went metric, then there would no longer be any need to assume anything but metric anywhere, and it would be safer for it. Yes, there's a long standing tradition, but it only takes a couple of generations to completely change, and that would likely be hastened by being the last large country to do so and having a large cultural footprint on the rest of the world. If the US did convert to metric, in 3 or 4 generations the whole world would be metric, and there wouldn't be any "wrong assumptions", and it is making bad assumptions that lead to preventable failures. If China can manage to go metric, the US can too.
  - microcolonel 8y ago
    > however in any kind of academic, engineering or scientific contexts metric units are used almost exclusively This is true in the United States as well, but fueling a commercial airplane is not an academic, scientific, or even an engineering exercise. It is as routine and pedestrian as refueling a bus. > Your point about Americans assuming imperial units is precisely wwhy it's so dangerous that metrification hasn't happened there. Or maybe it's an argument for why "metrification" is itself dangerous. The problem is the transition, not being on either side of the fence. It seems to me that the only safe mode of transition is first to dual readout, and only then to SI-exclusive. Don't get me wrong, I like SI units, I use them every day, and I don't long to spend any time multiplying and dividing by irregular fractions; I just don't like the dismissive "shoulda been metric" rhetoric that floats around everywhere; as though you can just stop selling letter paper and force everyone to use A-series compatible envelopes, and convert the clean (if baroque) markings on the paper products to bizarre decimal fractions of a g/m² without any empathy for the old guard. Some people care about how Britain still drives on the wrong side of the road, but that doesn't mean they should berate you every time a drunk roadtripping Frenchman turns out into oncoming traffic.
mertd 8y ago
Lives would also be lost in the ensuing confusion if US were to switch to the metric system.
- trothamel 8y ago
  Indeed. It's only due to the skill of the pilots that lives weren't lost during the Gimli Glider incident.
  - magduf 8y ago
    Only partially. Part of it was pure luck, that no one was on the track at that moment when the plane landed on it. There were people at the track at the time, doing races, but the plane just happened to come down at the right time.

I wonder how many lives are lost each year (not just in aviation but globally) because the US refuses to convert to the metric system.

by eterm 8y ago

I wonder how many lives are lost each year (not just in aviation but globally) because the US refuses to convert to the metric system.

hn_throwaway_99 8y ago

Or spacecraft lost: https://en.m.wikipedia.org/wiki/Mars_Climate_Orbiter https://en.m.wikipedia.org/wiki/Mars_Climate_Orbiter

rzimmerman 8y ago
The loss of MCO is actually a very interesting story about both engineering culture (engineers noticed a problem but the organization didn’t respond to investigate/fix it) and the conversion to metric. The root came from NASA deciding to use metric on this project and a contractor using the wrong units. But it’s the kind of thing that the process should be able to catch and handle. It bugs me to dismiss this failure as “haha why doesn’t NASA use metric” because not only is it a direct result of NASA switching to metric, there are really good engineering lessons that get ignored.

microcolonel 8y ago

> I wonder how many lives are lost each year (not just in aviation but globally) because the US refuses to convert to the metric system. Keep in mind that the U.S. is not the only place where measures are mixed. If anything, British people end up using more measures than Americans. Here in Canada, we have a lot of things read out in both, because of the immense sticking power of customary measures. U.S. organizations are actively encouraged and (for the most part) fully allowed to adopt SI measures, but it's not like switching road sides, where everything makes sense after you hear "drive on the right now". Keep in mind that powered flight was basically entirely developed by Americans and pre-SI Brits, and already had more than fifty years of history by the time either pioneering country adopted SI in any significant way. It should not surprise you in the slightest that an American plane expected to hear fuel mass given as weight in pounds; in fact, it should astonish you that anyone is trying to measure it in kilograms in North America.

eterm 8y ago
I'm British, so you don't need to explain using mixed systems, however in any kind of academic, engineering or scientific contexts metric units are used almost exclusively. Yes, people still refer to height in feet and inches a lot, and we'll drink a pint (a real pint! None of your mini-pints!), but that does change over time. For example older people will use stone and pounds for their weight but being younger the doc doesn't bother telling me my weight in anything but kilograms so I don't even know my weight except in Kg. Even in Britain, in almost all engineering contexts, SI units would be assumed. Your point about Americans assuming imperial units is precisely wwhy it's so dangerous that metrification hasn't happened there. If the US went metric, then there would no longer be any need to assume anything but metric anywhere, and it would be safer for it. Yes, there's a long standing tradition, but it only takes a couple of generations to completely change, and that would likely be hastened by being the last large country to do so and having a large cultural footprint on the rest of the world. If the US did convert to metric, in 3 or 4 generations the whole world would be metric, and there wouldn't be any "wrong assumptions", and it is making bad assumptions that lead to preventable failures. If China can manage to go metric, the US can too.
- microcolonel 8y ago
  > however in any kind of academic, engineering or scientific contexts metric units are used almost exclusively This is true in the United States as well, but fueling a commercial airplane is not an academic, scientific, or even an engineering exercise. It is as routine and pedestrian as refueling a bus. > Your point about Americans assuming imperial units is precisely wwhy it's so dangerous that metrification hasn't happened there. Or maybe it's an argument for why "metrification" is itself dangerous. The problem is the transition, not being on either side of the fence. It seems to me that the only safe mode of transition is first to dual readout, and only then to SI-exclusive. Don't get me wrong, I like SI units, I use them every day, and I don't long to spend any time multiplying and dividing by irregular fractions; I just don't like the dismissive "shoulda been metric" rhetoric that floats around everywhere; as though you can just stop selling letter paper and force everyone to use A-series compatible envelopes, and convert the clean (if baroque) markings on the paper products to bizarre decimal fractions of a g/m² without any empathy for the old guard. Some people care about how Britain still drives on the wrong side of the road, but that doesn't mean they should berate you every time a drunk roadtripping Frenchman turns out into oncoming traffic.

mertd 8y ago

Lives would also be lost in the ensuing confusion if US were to switch to the metric system.

trothamel 8y ago
Indeed. It's only due to the skill of the pilots that lives weren't lost during the Gimli Glider incident.
- magduf 8y ago
  Only partially. Part of it was pure luck, that no one was on the track at that moment when the plane landed on it. There were people at the track at the time, doing races, but the plane just happened to come down at the right time.