Understanding Relationships With Co-Ordinates

[Rob Killins 897126]

I am working on understanding and amending my sectorfile by correlating fixes between aeronautical charts, Google Earth, and my Sectorfile. I'm getting confused because of the difference representation of co-ordinates from one application to the next. I need to know the best way of representing actual co-ordinates ina sectorfile.

 

An example ... a the fix ALKOG

 

The aeronautical charts : N50 01.78 ; W97 43.85

Translated to Deg° Min' Sec" (via http://www.gpsvisualizer.com/calculators) is N50° 1' 46.8" ; E97°43'51.0"

I use those co-ordinates to pinpoint ALKOG on my Google Earth

 

But the same fix in my sectorfile is represented as N050.01.80.000 W097.43.90.000 . I was under the (wrong?) [Mod - Happy Thoughts]umption that the sectorfile co-ordinates are represented also in Deg° Min' Sec" format. I'm doubtful, as I cannot enter N050.01.80.000 W097.43.90.000 into Google Earth as it isn't a valid co-ordinate. I don't know where the sectorfile co-ordinates came from and wonder if they are accurate based on the translation made above?

 

So ... is N050.01.80.000 W097.43.90.000 correct in my sectorfile? Or should it be N050.01.46.800 W097.43.51.000?

 

I'm very confused.

[Ross Carlson]

Sector file coordinates are in Degrees.Minutes.Seconds.DecimalSeconds, and thus N050.01.80.000 and W097.43.90.000 are not valid because they both have seconds values higher than 59. Maybe the sector file author was trying to specify the value in degrees, minutes, and decimal minutes? (Such as North 50 degrees, 1.8 minutes, and West 97 degrees, 43.9 minutes.)

[Brendan Chen 943434]

As Ross said, Sectors have coordinate format in Degrees (N050 or W097), Minutes (01 or 43), Seconds(80 or 90) and milliseconds (000) (DMS) separated by full-stops.

 

With the aerocharts' coordinate, its easy, just append three 0s at the end and fill the gaps with '.'.

 

There are other representations such as Degrees Decimal (DD), which is degrees expressed in decimal format, you will need to convert that to DMS before the sectorfile can take it.

 

You might like to have a look at this page and see the relationship between different coordinate formats: http://www.sunearthtools.com/dp/tools/conversion.php[\url]

[Rob Killins 897126]

Except you can't have values of 80 or 90 seconds right? The maximum second value would be 59?

[Brendan Chen 943434]

That's correct; Because you are referring to minutes and seconds, so 0 - 59 for 2nd and 3rd value, and 000 - 999 for 4th value.