5 ms·
'nm' is 'nautical mile', for anyone wondering
by tombh 7y ago
'nm' is 'nautical mile', for anyone wondering
- SirHound 7y agoYeah I did a double take. Close but surely not that close.
- rzzzt 7y agomissed by a whisker -> 90,000 nanometers apart
- acvny 7y agoClearly a mistake. Abbreviations for nautical mile are M NM or nmi. I guess the author has not heard about nanometer
- backspace_ 7y agoI guess you could take the context of the article. There would be no way to measure in nanometers in that situation. So if someone does not know that nautical miles was implied, it should be easy to infer that nm was not nanometer.
- StavrosK 7y agoI did infer that, but was extremely confused because I didn't know what else it could be.
- ogre_codes 7y agoThe source isn't really intended for general consumption. It's a briefing intended for pilots and others in the industry. The goal of these kind of documents is to help pilots and air traffic controllers to learn from their mistakes.
- mirimir 7y agoSure, but that didn't stop me from thinking "nanometer" whenever I saw it. Initially, I was wondering what font screwup could turn "km" into "nm".
- HeWhoLurksLate 7y agoSame! I was wondering A) how in the world they managed to get that closr and B) how they managed to measure it.
- _-___________-_ 7y agoIn an aviation context, `nm` is almost universally used for (and understood to mean) nautical mile.
- gdxhyrd 7y agoNM or nmi, but not nm. Confusion in units is never a good thing.
- nradov 7y agoThe FAA uses "NM" (capitalized) in federal regulations.
- nwallin 7y agoI don't think I've ever seen someone use M, NM, or nmi for nautical mile. I've only ever seen nm. I used nautical miles a lot in a previous career, in the context of aircraft mission planning. Telling people in the industry to use nmi or NM seems a lot like telling computer people to use MiB or GiB instead of MB or GB, or to pronounce gif "jiff". They're just not going to change.
- gdxhyrd 7y agoIt is going to change. I use MiB and GiB. I also use the ISO standard for dates, etc. Precisely because they are now standard. Saying it is not going to change is what makes things harder.
- burke 7y agoThe aviation industry: not exactly sticklers for metric usage.
- rovolo 7y agoThe Apollo flights used NM on their screens for nautical mile. [pic (right-most screen)] https://cdn.arstechnica.net/wp-content/uploads/2012/10/liebergot-eidophor1.jpg https://cdn.arstechnica.net/wp-content/uploads/2012/10/liebe... [article] https://arstechnica.com/science/2019/12/apollo-flight-controller-101-every-console-explained/ https://arstechnica.com/science/2019/12/apollo-flight-contro...
- semi-extrinsic 7y agoAlso "KFPS", presumably for "thousands of feet per second"
- solarkraft 7y agoThanks. 2 nanometers of distance would indeed be a bit low.
- analog31 7y agoIt's only a problem if the planes are both fermions.
- syncsynchalt 7y agoNautical miles are a fun unit. They are one minute of arc of the earth's surface (idealized), so it makes sense why they took hold in the two forms of travel that regularly travel great circle routes.
- anymane 7y agoNot nano meter :)