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Old 13-05-2019, 12:47   #1
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Units set to feet/nm ... measurements show as meters

I have my settings for feets/nm/kts, etcs ... but when I do a measurement on a chart it shows up in meters until I reach 0.1 nm (200 yds). Do I have a setting wrong or is that just how things are. TIA.
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Old 13-05-2019, 13:58   #2
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Re: Units set to feet/nm ... measurements show as meters

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Originally Posted by PJHoffnet View Post
I have my settings for feets/nm/kts, etcs ... but when I do a measurement on a chart it shows up in meters until I reach 0.1 nm (200 yds). Do I have a setting wrong or is that just how things are. TIA.
It is how things are, under one cable measured distances are displayed in meters for nautical miles selected as distance unit as the decimal value would make very little sense.
For statute miles selected as unit the value is in feet under 1/10 mile as it is obvious that the user has some problem with standard SI units.
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Old 13-05-2019, 14:36   #3
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Re: Units set to feet/nm ... measurements show as meters

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It is how things are, under one cable measured distances are displayed in meters for nautical miles selected as distance unit as the decimal value would make very little sense.
For statute miles selected as unit the value is in feet under 1/10 mile as it is obvious that the user has some problem with standard SI units.
Thanks for the response ... and understand the decimal nm comment, but perhaps yards would be better than meters since nm's are measured in yards?
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Old 13-05-2019, 15:30   #4
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Re: Units set to feet/nm ... measurements show as meters

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Thanks for the response ... and understand the decimal nm comment, but perhaps yards would be better than meters since nm's are measured in yards?
Looking at the map of the world with countries using the imperial system being the ones in red I tend not to agree...

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Old 13-05-2019, 16:13   #5
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Re: Units set to feet/nm ... measurements show as meters

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Thanks for the response ... and understand the decimal nm comment, but perhaps yards would be better than meters since nm's are measured in yards?
Originally nautical miles was defined as one minute of Arc along the great circle on the planet. So 60 nautical miles would be one degree along the circumference of the Earth.

As to meters just * 3 to get approximate feet. Close enough anyway.
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Old 13-05-2019, 16:38   #6
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Re: Units set to feet/nm ... measurements show as meters

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Originally nautical miles was defined as one minute of Arc along the great circle on the planet. So 60 nautical miles would be one degree along the circumference of the Earth.

As to meters just * 3 to get approximate feet. Close enough anyway.

The meter is more closely related to the nautical mile than the yard.

Citing Wikipedia: "The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole"
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Old 13-05-2019, 17:19   #7
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Re: Units set to feet/nm ... measurements show as meters

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Originally nautical miles was defined as one minute of Arc along the great circle on the planet. So 60 nautical miles would be one degree along the circumference of the Earth.

As to meters just * 3 to get approximate feet. Close enough anyway.



3.3 is close enough... *3 diverges from reality a bit too quickly
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Old 13-05-2019, 17:27   #8
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Re: Units set to feet/nm ... measurements show as meters

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Originally nautical miles was defined as one minute of Arc along the great circle on the planet. So 60 nautical miles would be one degree along the circumference of the Earth.

As to meters just * 3 to get approximate feet. Close enough anyway.

Originally and still is For those of us that use paper charts using the degrees of latitude from the margins is how we measure distance.



That said almost all other computer nav systems that I know have an option to set NM and yards for sub 2 cable distances.
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Old 13-05-2019, 17:36   #9
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Re: Units set to feet/nm ... measurements show as meters

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3.3 is close enough... *3 diverges from reality a bit too quickly
I've never worried about reality, too much.
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Old 13-05-2019, 23:58   #10
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Re: Units set to feet/nm ... measurements show as meters

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Originally and still is .
Picky but it isn't

Though so little difference it's safe to say it is.

Nautical mile approximates an arcminute - Ocean Navigator - January/February 2003
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Old 14-05-2019, 00:04   #11
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Re: Units set to feet/nm ... measurements show as meters

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Picky but it isn't

Though so little difference it's safe to say it is.

Nautical mile approximates an arcminute - Ocean Navigator - January/February 2003

Yea I couldn't be bothered getting into that. The guys who defined it didn't know that the Earth wasn't a perfect sphere; after all they had never seen it
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Old 14-05-2019, 04:54   #12
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Re: Units set to feet/nm ... measurements show as meters

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Yea I couldn't be bothered getting into that. The guys who defined it didn't know that the Earth wasn't a perfect sphere; after all they had never seen it
Some still think earth is flat. So no nautical mile for them.
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