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-   -   speed units VS "measure tool" units (https://www.subsim.com/radioroom/showthread.php?t=92633)

miker 04-29-06 07:27 PM

speed units VS "measure tool" units
 
What i think is foolish ,is that the speed is measured in knots(=nm/hr)
while the distance tool in the map measure in Km
So when you want to calculate the nm you have to make an extra calculation.
If i am wrong i am sorry and i would appreciate if someone know how to change the units in the distance tool in the map to nm

Thanks!!!

greyrider 04-29-06 10:40 PM

i dont think you can, because they are two distinct measurements.

km is a distance

knots is a speed

don1reed 04-30-06 12:00 AM

I agree with you, Miker. The Devs apparently are landlubbers at heart :lol:

km x .54 = nautical miles

malcymalc 04-30-06 03:46 AM

And 1 knot = 1.852km per hour

I did put together a rather basic Excel spreadsheet so I could calculate distances travelled by targets over time. It took a calculation out of my game and made life a bit easier.

Malcolm

irish1958 04-30-06 08:59 AM

Knots
 
Using 1 Knot = 2 Km/hr introduces only a 5% error and is accurate enough for almost all purposes.
irish1958

miker 04-30-06 09:26 AM

Quote:

Originally Posted by greyrider
i dont think you can, because they are two distinct measurements.

km is a distance

knots is a speed

I meant to change the distance tool units to nm or speed unit to km/h

irish1958 by using this technique of 1nm =about 2km is good ,this is what i am doing but for large distances you have to be accurate and then the distance tool might confuse you
Thanks

panthercules 05-01-06 10:51 PM

There is a neat mod/feature in GW (also available as a standalone mod, I suspect) that gives you a couple of pull-down charts you can drag over your nav map screen that give you the distance (in km) that a ship will travel over various time periods (one sheet lists time in hour increments, the other sheet in smaller increments - maybe 10-15 minute chunks) at various speeds - a very handy way of doing the conversions without having to compute anything.

Since the TDC range dials are marked in meters and not nm, having the nav map tool measure off meters actually is a good idea - otherwise we'd just have to do conversions the other way to set up our shots.

Dantenoc 05-04-06 12:31 AM

The metric system is the way to go for any serious endeavour, like science or war. Unfortunately, sailors are superstitious and very set in their ways, hence the use of odd and antiquated measurement units like nautical miles... which, by the way, is so inconvenient that it doesn't even have the courtesy to measure the same as a "land" mile, nor a "surveyour's" (I think that's what it's called) mile neither.

don1reed 05-04-06 03:33 AM

Hi Dantenoc,

I keep thinkin' about, Tavia, (fiddler on the roof)

TraDISHon

:lol:

Alyebard 05-04-06 06:01 AM

Quote:

Originally Posted by Dantenoc
The metric system is the way to go for any serious endeavour, like science or war. Unfortunately, sailors are superstitious and very set in their ways, hence the use of odd and antiquated measurement units like nautical miles... which, by the way, is so inconvenient that it doesn't even have the courtesy to measure the same as a "land" mile, nor a "surveyour's" (I think that's what it's called) mile neither.

:hmm:
But if you use to sail, 1 nm is equal a 1´ and is very useful when you try to find your position at sea with a sextant ( and is not very easy)

Dantenoc 05-04-06 01:48 PM

Quote:

Originally Posted by Alyebard
:hmm:
But if you use to sail, 1 nm is equal a 1´ and is very useful when you try to find your position at sea with a sextant ( and is not very easy)

Yes, but then again, that's only convenient if you stick to the 360 degree for a circle unit of measurement. Any serious discipline like calculus and such use radians instead of degrees to measure circles.... but I see your point that you can't convert some units unless you convert ALL the units (something which is unlikely)...

We still carry the burden of old civilizations that DID NOT use 10 as their "base" number, such as the romans and their love for the number twelve (hence you ask for a dozen eggs or say that noon occurs at 12:00) and other funkier base numbers like the SEXagesimal system (I admit I DO LOVE the name ;) ) which has 60 as it's base number (minutes and seconds, for example), and so on and so forth....

Let's hope that one day the whole world agrees to unify and we do away with silly things like remembering the length of a dead guy's foot or another dead guy's thumb :yep: .

miker 05-04-06 02:56 PM

Do you know that a NM is NOT everywhere the same distance.
As Alyebard wrote:"But if you use to sail, 1 nm is equal a 1´ and is very useful when you try to find your position at sea with a sextant ( and is not very easy)" if you use a map an 1´ is different in the Mediterranean sea and the north Pole ,thus when you plan your route on the map is not always good to consider 1nm=1852m (i mean big trips ,from one hemisphere to the other)

VipertheSniper 05-04-06 04:36 PM

Quote:

Do you know that a NM is NOT everywhere the same distance.
As Alyebard wrote:"But if you use to sail, 1 nm is equal a 1´ and is very useful when you try to find your position at sea with a sextant ( and is not very easy)" if you use a map an 1´ is different in the Mediterranean sea and the north Pole ,thus when you plan your route on the map is not always good to consider 1nm=1852m (i mean big trips ,from one hemisphere to the other)
Just read up on wikipedia on that subject, because I didn't quite get what you wanted to say, but now I get it, your way of saying it is a bit confusing tho, lets just say that per the old definition, that 1' is 1nm, the nautical mile doesn't have the same length at the equator than it has on the pole because the earth isn't a perfect sphere. The international definition for the nautical mile is that it's 1852m EXACT which is very close to the average length of one minute of latitude i.e. one minute of arc along a line of longitude (a meridian).

Apart from that, we've got GPS nowadays, and when that fails I think whether you're using the 1nm=1' rule of thumb or calculate your minutes of latidude accuratly won't matter that much.

don1reed 05-04-06 06:47 PM

Quote:

Apart from that, we've got GPS nowadays, and when that fails I think whether you're using the 1nm=1' rule of thumb or calculate your minutes of latidude accuratly won't matter that much.
except when your batteries fail... :yep:


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