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    Coordinate precision // SAR
    From: Brad Morris
    Date: 2019 Jul 4, 11:19 -0400
    Paul provides sound advice.  If you can provide your position in DD°MM.M' format, then do so.

    However, and this is a big one, do not convert the position on your screen to that format.  Just read the numbers as clearly as you can, just as you see them and importantly, get them to repeat them.  You are likely to make a mistake in the conversion.  Do not convert.  Read the numbers you see.

    I went on a search to find what SAR actually wants.  

    There are 3 findings

    1) Joint Pub 3-50 NATIONAL SEARCH AND RESCUE MANUAL VOLUME 1: National Search and Rescue System.

    Defines Position: Either of two alert solutions representing a geographical place normally expressed in degrees and minutes of latitude and longitude.

    2)  your EPIRB/PLB reports your position.  You did register it, right?

    degrees latitude minutes latitude 
    0 = north; 1 = south 
    degrees longitude minutes longitude 
    0 = east; 1 = west 

    3) Digital Selective Calling 

    That red button on your VHF radio.  You did get an MMSI, right?

    Distress Coordinate

    Distress coordinates are to be encoded five parts, sent as a string of ten digits. The first digit indicates the direction of the latitude and longitude, with "0" for North and East, "1" for North and West, "2" for South and East, and "3" for South and West. The next two digits are the latitude in degrees. The next two digits are the latitude in whole minutes. The next three digits are the longitude in degrees. The next two digits are longitude in whole minutes.


    What I found to be just a bit surprising is that SAR just wants your position to the nearest 1 nautical mile.  Further, Pub 3-50 indicated that they do NOT want your position stated as "two miles south east of bird rock" because of the commonality of names among different locations and the extra steps needed to confirm your location when you are in extremis.  

    Just give your position, in any numerical format you can.  They will get it done.


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