I like metric. Admittedly, I've never really "known" the pre-metric stuff, since I was born into a country almost 3 years after it went metric 1966 here). However, I did get to learn some small facets of imperial when I started gaming and then the length units became more or less interchangeable. Metric,however, is simple, neat and scales easily. 100*c - you're dead. 0*c -it's cold, but with clothing and shelter, you'll live. Without them, you will be dead in hours from hypothermia. 100*c - you're dead. 1000 millimetres to the metre, 1000 metres to the kilometre. 1000 milligrams = 1 gram, 1000 grams = 1 kilogram, 1000kg = 1 tonne, 1000 tonnes = 1 kiloton, 1000 kilotons=1 megaton, etc.
They were? In that case, you're forgetting that these are people who constantly need to convert between (a) SI and (b) US in order to (a) do their job and (b) be able to present it to their boss.
I work in aerospace manufacturing, and while it’s not difficult to convert between metric and English units, it introduces “hassle” into the process, and hassle is the enemy of productivity. Further, our standards are written in English units and straight up conversion would essentially randomize them. For example, alpha case removal is based on forming temperature, with neat cutoffs at 100 F intervals. 1100-1199 requires this removal, 1200-1299 requires that removal, etc. converting to SI would make that 593.3-648.3 and 648.9-703.9 respectively. That’s a LOT less intuitive and that introduces hassle again. Also 1 degree F is less than 1 degree C, but not neatly so. To get the same granularity in measurements, you’ll need to include decimal points and that gives us another possible point of failure in hand-written records. Rewriting our standards to SI units across even just the aerospace industry would be a huge undertaking. Going the opposite direction, we have infinity as an example. As written, range bands are in neat 20cm intervals. In the States, those are 8” intervals; again, much less intuitive. There is also the problem that the conversion errs on the side of playability over accuracy. 8” is greater than 20cm (meaning American HMG’s shoot further than everyone else’s. Murica! F Yeah!).
We were talking about a different system, not using two systems with regular conversion between them, that's another can of worms.
In this case a pretty spectacular and expensive worms ;) https://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_failure
Your forming aerospace components and relying on hand written notes, no offence but your company isn't long for this world.
Because those standards are arbitrary pretty numbers, and you need to adjust those arbitrary pretty numbers to look nice in a different scale. Because whatever chemical processes you have don’t come with neat cutoffs at 100F intervals. Because I’ll see anyone who claims that inches (and fractions of inches) are nice and convenient, and put them in a room with land surveyors and their decimal feet. “Within a tenth of a foot” and “within an inch” both sound nice and are equally arbitrary boundaries. So I take it you’ve never heard of the ‘1 inch = 2.5cm’ wargaming compromise standard? A.k.a “How do we get reasonably nice numbers in both systems?”
The way I usually teach (taught, actually... I dropping Thermo from the curriculum this year) the usefulness in °F is that most weather on Earth falls between 0 and 100 most of the time. For example, where I live currently, we see temps in the 70's during the day and 40's during the night. Scales of 10 or 100 are easy for us... probably because most of us have 10 digits readily available to us (and another 10 hiding away in foot coffins). But then, Kelvin is the only one that matters because it's the only one where doubling the temperature actually doubles the thing temperature depends on.
Perhaps. Data entry has the same issue, though. We will always have to have piece count and inspection accountability. Numbers don’t become more accurate just because you typed them. Completely aware of that, but every company would have to revise every standard. For very little actual benefit. I get that, but it still sacrifices accuracy for playability. It also doesn’t change the fact that 20cm is probably easier to picture for native metric users than 8” is for native English users.
This is where you are wrong, typed data can be mined for all sorts of things. Operator A always writes the same number to the same decimal while operator B has a standard deviation of +-0.5F, either Operator A is fudging the numbers or operator B is sloppy on the same process. Thats just the tip of the iceberg, I work for a fortune 500 and its one of the biggest focuses right now is digitizing all process and using deep learning to adapt.
Sure, SPC, right? The point of input is a failure mode, though. Obviously miskeyed numbers are obvious, but on a keypad the four is right above the one. Can you identify from the data itself whether that number should be a 1 or a 4? Especially when it represents a small interval (like .004”)? I get what you’re saying, but data integrity is super important to my position. A portion of our CI is focused on how we can ensure data integrity (ideally with automated data entry). Practically speaking, though, there are problems with implementation.
Blame the government. There's a lot of crap that has to be included in aircraft maintenance. Hey, I replaced an entire wing skin (because it was easier than patching a crack that big): OK, fill out FAA form 337, complete with drafting instructions on how you made the new skin.
Blame the aviation safety community for that: the government just enforces the requirements. There's a reason why flying is the safest way to travel. Re: native metric users being able to tell 20cm easier than a native Imperial user being able to tell 8". This is complete BS. The Australian Infinity community universally uses Inches (blame GW) and we're almost all native metric: I know many people who convert small distances to inches in their head for estimation (I usually do). The issue is familiarity not anything else. The only non-metric measurement that I think actually makes practical sense to use is nautical miles and that's because it's derived from 1 minute of latitude. Doing nautical calculations in metric sucks (although is tractable if you're doing entirely digital navigation).
Not only that, there are very interesting equivalencies you can do with SI. For example: "One cubic centimetre of water is the same as one mililitre of water, and one mililitre of pure water weights one gram. To raise it’s temperature by one degree centigrade, one calorie is required".
