Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Re: SAR-search-patterns Application
    From: Brad Morris
    Date: 2019 Jul 16, 20:16 -0400

    In another thread, I found that the EPIRB / PLB message that is transmitted to the satellites is only to WHOLE MINUTES.  Fractional minutes (tenths) are not transmitted. I stand ready to be corrected on this point, but the data is fairly clear.  I was surprised by this, as the search area is now a one arc minute by one arc minute box.  That may be okay if you are in a big orange lifeboat, but a head bobbing in the water will be much tougher to see.

    The purpose of the 406MHz message is to "alert" SAR.  This will put air search over your location.  If your EPIRB/PLB has the 120MHz homing signal, this should help SAR in the "locate" phase.  There are other means to assist in "locate"(flares, smoke, etc).  The "find" phase will always take mark one eyeballs.  Alert, locate, find.  Each phase of your strategy should be considered.

    A small, waterproof, handheld VHF radio should be a part of your go bag.  A Digital Selective Calling (DSC) Distress message also transmits your position, but again, only to WHOLE MINUTES.  Fractional minutes are not transmitted.

    It seems obvious that when speaking with SAR, that this is your only chance to narrow a search area by a factor of 100!  That is, instead of one by one arc minutes, it is now 0.1 × 0.1 arc minutes, provided you tell them and they can utilize that data.

    I am waiting patiently for James Campbell, an instructor at the National SAR School, to provide us some data points.  He spoke up in that other thread.  I can only hope that he does so again, or some other authoritative source will contribute.  


    PS Yes, I do have an EPIRB/PLB.  It is a link in my strategy.  I agree that if you want to be found, it is an excellent tool.  Reliance on a single device, with a single point of failure, may not be the wisest strategy.

    On Tue, Jul 16, 2019, 7:03 PM Zane Grey <NoReply_ZaneGrey@fer3.com> wrote:

    If you want to be found the one thing you want is an GPS enabled EPIRB! Takes the search out of search and rescue!

    View and reply to this message

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site