What is your backup GPS solution?

Discussion in 'Ask All Sailors' started by Jackdaw, Dec 6, 2018. Add this thread to a FAQ

  1. Jackdaw


    Joined Nov 8, 2010
    10,076 posts, 3,083 likes
    Beneteau First 36.7 & 260
    US Minneapolis MN & Bayfield WI
    If you really rely on GPS for navigation and piloting,you need to have a robust backup plan for when your primary fails. Often the cause of the failure can take out back ups. You need to have one device you can count on when the chips are down. What is yours?

    Here is mine, and why: GeoNav 4C

    This device was a gift from the President of Navionics, and has stood the test of time. Here is why:

    Bulletproof. You can drop it. You can stand on it. You can through it at an pirate, disable him, and then use it to navigate your escape. Totally waterproof of course.

    Flexible power: It runs for days on 4 rechargeable 2800mAh AAs - rechargeable in the device via a cig lighter cord, but you can throw in disposables into it in a pinch.

    Worldwide on-board cartography: Not everyone needs that, but it for sure has to cover wherever you might go. This unit has a 16G Navionics Gold+ card with full global coverage, no cell coverage needed.

    Marine device. This is a full-on marine GPS, will every feature you'd expect on your big plotter, but in handheld size.

  2. rgranger


    Joined Jan 19, 2010
    6,123 posts, 1,604 likes
    Hunter 26
    US Smith Mountain Lake
    When I go to the coast each year, I carry two hand-helds and a set of booklet sized NOAA charts.

  3. dlochner


    Joined Jan 11, 2014
    3,617 posts, 1,672 likes
    Sabre 362
    113 US Fair Haven, NY
    Oh the GPS's we carry.

    There is the one on B&G MFD.
    The one in the Vesper Marine AIS.
    The one in the Standard Horizon VHF
    An older Garmin handheld (72 C?)
    2 iPhones
    2 iPads

    That's all I can remember, is 8 enough?

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  4. jon hansen

    jon hansen

    Joined May 25, 2012
    1,934 posts, 1,609 likes
    john alden caravelle 42
    us sturgeon bay, wis
    garmin 76 hand held, black and white screen, and a newer garmin 78 color screen were purchased as 'backups' for a fancy chatploter down below. for real life usage, i rarely turn the ships gps below on anymore. just have the black and white near the helm just in case.

    i like having the paper charts out for where i'm sailing so the crew can all ponder the big picture.

    Last edited: Dec 8, 2018
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  5. victorhoisington


    Joined Jan 22, 2008
    230 posts, 52 likes
    Islander Freeport, 41 Ketch
    US Longmont, CO
    The New Raymarine 9" MFD works well, the older Garmin is still working, as mentioned by others, I have 2 iphones and 2 ipads aboard all with multiple nav apps and maps loaded, plus the SH VHF and paper charts. My handheld GPS has died so needs to be replaced, I also have a sextant and current site reduction tables on board, although I'm still learning the sextant so would probably be off by a few miles.

    Line of site and dead reckoning also work for me since I'm sailing mostly SF Bay and near coastal, fog is the big issue here. but absent fog, I can find my way around both day and night with minimal issues. Even here I can tell the difference between traffic lights and buoy/ship lights, for me at least, its not as hard as some describe.

    Is that enough backup, the issue I'm most concerned with today is not so much loss of things on the boat as loss of satellite communications which causes much bigger issues than my simple navigation problems.

  6. David in Sandusky

    David in Sandusky

    Joined Nov 8, 2007
    1,160 posts, 186 likes
    Hunter 27_75-84
    US Sandusky Harbor Marina, Lake Erie
    All 3 of our older Garmin handhelds back up the current new one. My iPhone with Navionics is always close by (It’s our weather source.) We always have paper charts available, and maintain a current (last half hour) position plot when we are outside our home waters.

    Piloting and/or dead reckoning will get us where we are going if all electronics are down. (Lightning strike?)

    Back in 2001, we lost gps coverage an hour out of Gore Bay. None of our gps’s worked. Compass courses kept us away from a shoal, and headed close to the right passage through the islands ahead into the Whaleback Channel. The Admiral’s brilliant piloting with our charts and binoculars found the exact location of our passage, and set us up for an easy leg to the Bear Drop anchorage!

    Last edited: Dec 6, 2018
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  7. Gunni


    Joined Mar 16, 2010
    5,943 posts, 1,488 likes
    Beneteau 411 Oceanis
    US Annapolis
    That there is a pink unicorn!

    Why can't I find the GeoNav 4C for sale?
    Not even listed on the Navionics website.
    I have an iron rule when it comes to tech stuff - robust phone support.
    Not real happy with some of the Garmin product support, but I have had a number of their handheld marine GPS. The GPS Map 76 sits in my ditch bag, but the Garmin88 was killed by alkaline battery leakage this year - 8 bells old friend.

    Have a backup Garmin beast - GPSMap640. battery, hardwired, land and sea. Robust and easy to use. Sits in a cradle at the nav station, ready to go on deck as plan B. Garmin did not make it easy to update charting.

    Support for the Map76 is done, even though it works just fine. Planned obsolescence I suppose. Big investment in proprietary Garmin chartography - up in smoke. Unacceptable.

    Finally, I have an independent (has it's own antenna) Raymarine fixed mount at the nav station, about 12 years old and workable, but it is some clunky software. At least it works, but nobody I sail with that hasn't used a 12 year old computer would know what to do with it.

    I'm shopping. Even if I have to learn a new system. Already know navionics (Navico) and own it, so this is a possibility.

  8. Scott T-Bird

    Scott T-Bird

    Joined Oct 26, 2008
    3,907 posts, 909 likes
    Starwind 27
    US Barnegat, NJ
    I have B&G 7" chartplotter with 2 handhelds and navionics on the phone. The handhelds are Garmin 76cs and 78sc. I used the 76cs on the lake and only had the lakes chart. When I wanted to purchase the Blue Chart for coastal, it was too late! They didn't have any for the 76 so I ended up buying the 78sc with Blue Chart. The 76 is still a useful backup since it has a basic map and I can always display position. I can also feed position to the VHF radio from a handheld if I want to, but the radio will be on the chartplotter network. I also have a garmin remote antennae, which I think I'll use so one of the handhelds can be useful while mounted in the cabin.
    I bought a nice book of full-sized charts from WM that covers from Delaware Bay & Cape May and up the coast to Block Island, Narraganset Bay and the Hudson River. It's nice to look at but I haven't found it useful yet. ;)

    Those handhelds go thru some batteries!

    Last edited: Dec 6, 2018
  9. leo310


    Joined Dec 15, 2006
    135 posts, 47 likes
    Catalina Catlina 310
    CA Campbell River BC
    Main is a Garmin 840sx backup (portable) Raymarine C70, 1 ipad and 1 pc Laptop

  10. thinwater


    Joined Mar 26, 2011
    2,280 posts, 543 likes
    Corsair F-24 MK I
    US Deale, MD
    Really? I had GPS fail back in the early days. I used a map and compass for hundreds of miles of complex coastal piloting. Before that I did trips without GPS.

    When the chips are down, use eyes, map, and compass. Sailing 101. OK, maybe 102. But really mid-school geometry.

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  11. Charlie Jones s/v Tehani

    Charlie Jones s/v Tehani

    Joined Mar 1, 2012
    1,735 posts, 683 likes
    1961 Rhodes Meridian 25
    us Texas coast
    Garmin 76CS, a laptop with charts. and my Iphone with INavx.

    On a delivery trip to Mexico on a 41 footer, we tore a jib badly. Not enough fuel to motor to Isla Mujeres, but not that far from Progreso in the Yucatan. Found the boat had zero charts for Yucatan in the installed chart plotter. Nada
    Navigated from roughly 100 miles out to right between the jetties with the Iphone

  12. SFS


    Joined Aug 18, 2015
    1,608 posts, 524 likes
    Hunter 31
    US Tampa Bay
    In no particular order:
    2 cell phones
    GPS dongle for either of two computers
    Old Garmin handheld GPS
    Tablet with internal GPS
    Garmin InReach

  13. Bad Obsession

    Bad Obsession

    Joined May 23, 2004
    3,289 posts, 109 likes
    N/A N/A
    US Colonial Beach
    Sorry....but for back-ups when coastal cruising you will never replace a compass and a good set of charts.

  14. Captain Larry-DH

    Captain Larry-DH

    Joined Jun 14, 2010
    675 posts, 365 likes
    Quorning Dragonfly 1200
    US home
    Lots of redundancy but if the DOD alters the satellite system I have a paper chartbook and 2 bearing compasses aboard, pus a steering compass.
    I hope it never comes to that.

    Last edited: Dec 6, 2018
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  15. Ken Cross

    Ken Cross

    Joined Oct 24, 2010
    1,946 posts, 316 likes
    Hunter 30
    US Everett, WA
    In addition to the plotter we have smart phone with charts, iPad with charts, hand held Garmin with charts, and paper charts.


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  16. Jackdaw


    Joined Nov 8, 2010
    10,076 posts, 3,083 likes
    Beneteau First 36.7 & 260
    US Minneapolis MN & Bayfield WI
    So here is my bigger question... do multiple devices of questionable reliability actually provide solid fail-safe backup?

  17. Jackdaw


    Joined Nov 8, 2010
    10,076 posts, 3,083 likes
    Beneteau First 36.7 & 260
    US Minneapolis MN & Bayfield WI
    That’s another question!

  18. LeslieTroyer


    Joined May 20, 2016
    2,582 posts, 1,203 likes
    Catalina 36 MK1
    US Everett, WA
    Let’s see if the GPS in my chart plotter goes out, there is one in my phone, one in the AIS one in my hand held vhf. I think I’m good

  19. MikeHoncho


    Joined Dec 28, 2015
    299 posts, 122 likes
    Laser, Hunter H30 Standard
    Un Tacoma
    Alot of people are listing IPADs. I was excited when u got my IPAD gen 6 from work to use then I found out they don't have GPS! You have to have a cell version. You guys with the IPADs all have cell on them?

  20. Mark Maulden

    Mark Maulden

    Joined Jan 25, 2011
    1,910 posts, 222 likes
    S2 11.0A
    US Anacortes, WA
    Well, whatever took out your electronics and not your geonav would probably also leave my 78sc still working. (Also have iphone/ipad etc). If after the event, you decide to drop it, drown it, etc..the geonav might survive the 78sc but that’s highly improbable and you have to look at the common mode failure effects. 1) voltage regulation could disable any connected electronics..2) lightning strikes can do strange things. Even to your geonav..3) gps slewing for whatever reason. 4) electromagnetic pulse. Hope it never comes to that but if it does, it’s academic..So you could put this into a failure modes and effects analysis and come up with the best backup scenario being a paper chart procedures. You could also put this into a probability analysis and not worry about it assuming you have paper and knowledge..

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