METAR simple question
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gkainz
Final Approach
Oh time to nit pick. No such thing as nautical MPH
Sac Arrow
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I would guess because "they" figure statute miles are easier to estimate.
Oh? That's interesting.
Dan Thomas
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Dan Thomas
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There are plenty of inconsistencies in aviation. Winds directions on the ground are given in magnetic direction. Aloft, they're give in true. Altitude is in feet, temperature in Celsius. One of the more puzzling is the habit of some Avgas manufacturers to give the lead content in grams per gallon.
Go figure.
Dan
Shawn
En-Route
Good grief...I really don't want to throw away all of my tape measures but can we please just join the rest for the ENTIRE world and just go metric as the standard already!
MikeELP
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OK, you've made some points but I can give you good reason for these(except that fuel thing). Wind on the ground affects planes which are stationary, taking off or landing, so reference to the mag will give orientation info in keeping with the runway alignment which is in mag. That makes sense. Winds aloft in true for the opposite reason. Once aloft, you are in a lightly viscous medium, and you are carried by the wind in true, not mag, although getting it in mag wouldn't be too much work to handle. So again, there's some sense behind the frame of reference. Altitude in feet because the entire fleet of US aircraft have an instrument calibrated in that scale. Sensible. Temp in C is a little tougher, but I can see the reasoning for ICAO compatibility, and general acceptance in the US as well.
But all this stuff makes modest sense except when the first part of the METAR is calibrated for NMPH(or Knot, for the retentive), and the very next descriptor being calibrated in statute. It would be like the temp being in C and the dew point in F or vice versa. No reasoning, and just saying that it's one of those things gives me pause.
John Baker
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gkainz
Final Approach
Ok I apologize. Read too quickly and read it as knots per hour - you stated it correctly.
ColoPilot
Line Up and Wait
The metric system is for people who are bad at math.
jonnyjetprop
Cleared for Takeoff
Sometimes the best answer is "because".
Yeah, it's right up there with 'we have always done it that way'. Not really suitable.
MAKG1
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There are a lot of historical oddities out there. Less in aviation than elsewhere as it's barely 100 years old.
If you want to make your head explode, look up the history of stellar magnitudes (it goes back to Hipparcos). Or star types (O B A F G K M ?? Really?).
If you want to make your head explode, look up the history of stellar magnitudes (it goes back to Hipparcos). Or star types (O B A F G K M ?? Really?).
jonnyjetprop
Cleared for Takeoff
While you may disagree, there are many things done a certain way because they have always done it that way.
As to way visibility is reported in statue miles, I can speculate:
The weather reports are used for non aviation purposes too.
Non aviation people are used to thinking in SM.
The old Airport Traffic Areas were defined by SM.
Historically data might be in SM and the weather guys might want to be able to compare.