Handheld GPS as backup, why bother?

[Kenomac]

Buy a couple of spare batteries for your smartphone, and turn it off when it's not in use. Who you gunna be talkin' to when your more than 10 miles offshore anyway? Expecting a call?

[hamburking]

Originally Posted by FamilyVan

Ive mentioned this in other threads but the Garmin etrex is only about $100 or a bit more and they are bomb proof. I lost it on my motorcycle in 2005 and ditched at over 90 kph, but I still use the old etrex as my primary GPS.

I also use an old Garmin Etrex. Actually, I have a pair. Yes, they are bulletproof. And they are cheap...used under $50. I traded a bike for one. Yellow, basic model, no maps. Runs 24 hours on a pair of AA. Waterproof.

I crossed the atlantic with it. Sure, there was a big fancy chartplotter and other electronics aboard, but when battery power started getting tight, that got shut down first. I could lay in my bunk and know our position, course, speed, and distance remaining. If I needed to call for help (heaven forbid), I had my exact position right in my hand.

When at anchor, I mark a WP at my boat, then take the etrex with me in the dinghy. Its amazing how everything can look so different coming back, especially if the wind direction has changed, or the sun has set. Having that big arrow pointing me home takes all the worry and grief out of it. Also knowing the distances involved helps me calculate travel time, and fuel needed more accurately than a guess.

Also at anchor, I set a WP before dark. Then I keep the etrex handy. I can check my distance from that original wp without getting out of my bunk. Its a lot easier than going up on deck. It tells me I'm right where I should be. And if it tells me I've moved more than a few metres, then I know I need to get up and do something. I used to mark a WP at the anchor, then it would tell me my scope. So long as the distance to the anchor wp remained constant, I was somewhere on a circle about my anchor. Unfortunately, I sail alone these days, so I can't mark the wp and drop the anchor at the same time. But I make do.

And finally, I bring my little etrex when I'm visiting a new port ashore. After a day running errands in Antigua, my crew was not quite sure which road to take home. My little yellow box knew the exact distance, and pointed us in the right direction.

I consider my Etrex as essential gear. The CP, electronics, iphone, and ipad are just niceties I can do without. I can't imagine being in a storm holding an ipad, but I have used my etrex in driving rain many times. When on night watch at sea, my pockets contain my etrex, small light, whistle, and food.

[Joe Brown]

Sounds like you have a good deal of backup for electronic navigation. My first choice is paper charts - with electronic backup. Perhaps I'm a nerd, but I enjoy plotting my courses on paper and feel I have a better understanding after that preparation.

[valhalla360]

Originally Posted by Capt.Don

No one has mentioned battery life. My handheld GPS can go for a couple of days on a pair of AA batteries. My iPhone is lucky to go a day without recharging. I'm for a backup GPS with spare batteries.

We were over in europe and used it for mapping around cities but turned off the cellular service and other radios. I easily got a week or more on a charge if just checking out position occasionally.

Also, if you main battery bank is still available, it's easily rechargeable many times over. Run out of disposable AA batteries and your handheld is done.

The only issue with tablets and smart phones that I see is the waterproofing but that can be solved with a case.

[noelex 77]

They seem to be putting GPS chips in everything these days. My number of GPS units is growing exponentially without trying. Often with their own battery supply.

The smartphones etc often have more modern and sensitive GPS chips than the marine units. Generally the antennae is more of compromise, nevertheless they do a great job and are more likely to have GLONASS capability, although exactly how much this contributes to the value of the fix and more importantly a fix in the very remote possibility that the GPS system went down remains unclear.

The area where marine HH GPS units have an edge is waterproofness, as well as simple robust software that does nothing superfluous. Some have a screen that is more suitable for viewing in sunlight. So I think they still have some place, but it suspect my Garmin 62 is the last marine HH I will buy.

Make sure you put a couple of units away with some lightning protection. I wrap them in aluminium foil in a waterproof bag in a metal box that in turn is inside an aluminium hull away from the likely current path. They are not immune to a bad direct strike, but I would have more serious concerns with a strike of this magnitude.

Don't forget GPS is not very helpful without maps. Knowing your position is X XX XX.XX, Y YY YY.YY is really of not much help at all. Maps are much more important than a position fix.

However, many GPS units these days have map capability so the electronic map redundancy is growing at a similar rate.

[tbodine88]

Not that I could use one, but you may perhaps carry a Great Plastic Sextant just in case

[noelex 77]

Just a final note: In the event of a significant problem there is no need to expect a continual position fix. In the "good old days" of celestial navigation a fix once a day was considered good.

Used like this the battery supply of any single GPS would survive the longest and slowest voyage.

It is likely that using a spare GPS far more frequent position fixes could be obtained without any concern about battery supply. A continuous, accurate position fix is a wonderful thing, but it is a luxury that has only been possible recently.

[FamilyVan]

Originally Posted by noelex 77

They seem to be putting GPS chips in everything these days. My number of GPS units is growing exponentially without trying. Often with their own battery supply.

The smartphones etc often have more modern and sensitive GPS chips than the marine units. Generally the antennae is more of compromise, nevertheless they do a great job and are more likely to have GLONASS capability, although exactly how much this contributes to the value of the fix and more importantly a fix in the very remote possibility that the GPS system went down remains unclear.

The area where marine HH GPS units have an edge is waterproofness, as well as simple robust software that does nothing superfluous. Some have a screen that is more suitable for viewing in sunlight. So I think they still have some place, but it suspect my Garmin 62 is the last marine HH I will buy.

Make sure you put a couple of units away with some lightning protection. I wrap them in aluminium foil in a waterproof bag in a metal box that in turn is inside an aluminium hull away from the likely current path. They are not immune to a bad direct strike, but I would have more serious concerns with a strike of this magnitude.

Don't forget GPS is not very helpful without maps. Knowing your position is X XX XX.XX, Y YY YY.YY is really of not much help at all. Maps are much more important than a position fix.

However, many GPS units these days have map capability so the electronic map redundancy is growing at a similar rate.

While you do have a good point, I use my old pre charting handheld for everything from duck hunting, mountaineering, off roading, motorcycle touring and of course sailing. I have dozens of waypoints programmed in to it. So if I've been some where before (ie, create a waypoint when I leave my anchored boat), I can find my way back without the benefit of a chart. Or, if I have time to research my chart before I depart, I can (and do) enter all of my waypoints before departing.

For example, I have been manually entering waypoints into my GPS for a some 300 mile trip from western Lake Ontario to well down the St Lawrence river via the thousand islands. What this means from a practical perspective is I can sit out in my cockpit in the mooring rain with my GPS on my lap and my charts, cell phone and lap top safely down below on my chart table where it's dry.

Sent from my SGH-I547C using Cruisers Sailing Forum mobile app

[W3GAC]

Yes, like many of us, you have many gps alternatives. But the one common link of possible failure is a lightning strike to the boat as many have voiced concern. It is not uncommon that when a boat takes a direct or even close by lightning strike... EVERYTHING that is electrical that is CONNECTED to either the 12v system or 120v AC system may likely be fried. Unfortunately, there aren't many alternatives to the common practice of plugging in these devices to the boat's 12v or 120ac electrical systems to charge them... often for 8-12 hours everyday. This is a significant percentage of exposure time and If they happen to be to plugged in when a lightning strike occurs... they all are likely to be fried. While we might try to manage how many/ which ones are plugged in... the reality is the one time it wasn't might be the time it's your turn to be the lightning rod.

I believe most of us that have done extensive cruising in lightning prone areas pretty religiously keep a good AA battery powered marine HT and hand held emergency GPS in a shielding metal container with many spare batteries. It's very very cheap insurance.

By the way, it doesn't take a lightning strike to shut down all navigation/ electronics. Even well maintained boats can suffer a complete electrical failure anytime from an unknown corrosion issue, shorted battery, chaffed wiring that suddenly shots, an alternator that silently fries/ stops working and battery voltages drop unnoticed until your electronics suddenly shutdown (read below), and many other causes that often keep cruising captains awake at night thinking about/ mentally preparing a solution to. While some of these may have work arounds given some time and ingenuity... consider a complete electrical blackout running up the coastline at night in a storm... or getting caught in dense fog and everything going black.

On a recent delivery to NYC harbor, with a failed alternator/ and sagging battery voltage now below the onboard electronics threshold, we ran into the worse dense fog I've ever encounter just as we entered Ambrose Channel, one of the busiest shipping channels on east coast. With ships behind us coming in and in front of us coming out, we had a 4 AA battery powered emergency Garmin GPS/ plotter and AA battery powered HT that allowed us to get to/ stay just outside to the right of the channel and communicate/ respond to the tankers/ container ships who were keeping close watch on us with their radar.

It is nice to know you have a complete (waterproof) independent GPS & HT just steps always that can be up and giving you vital position/ heading/ communications info you need in a minute or two.

Those of us that practice this usually shut off the normal electronics every few weeks to ensure they work and still have a good supply of fresh batteries... and/ or use them during some dink shore/ exploration trips.

These practices also a good to remind everyone else onboard where they are in case the lightning takes you out along with the electronics! I store my emergency HT and GPS/ Plotter in a duffel Go Bag like others have mentioned.


Sent from my iPhone using Cruisers Sailing Forum

[RichandHelen]

Originally Posted by hoppy

Ever since I bought my boat I have expected that one day when I plan to do some serious passage making, then I will buy a handheld GPS as a backup.

I'm now wondering if there really is any point....

My yacht has 2 MFD's, one at the helm and one in the cabin, plus I have an iPad & iPhone with Navionics maps and my Macbook has MacENC installed and I can plug it into the AIS transponder to get my position. So I have 5 ways to navigate without needing to resort to paper. I may also carry a 2nd iPhone with me for a 2nd sim card and that also has Navionics on it, so make that 6.

In addition to these, I have a Yellowbrick tracker that can display the GPS coordinates and when I finally do some serious passages, I'm most likely to buy an Iridium Extreme which also has GPS.

I'm more than covered for normal unit failure. I have plenty of portable GPS's to put in the oven during an electrical storm and in the event of a total electrical failure, the Yellowbrick has a much longer battery life than any portable GPS.

I have read people mentioning the benefits of a HH GPS when in the dinghy, but that only seems to be useful if you have a map version and paid for the local maps, and as I will get a waterproof case for my iPhone to protect it when I take the dinghy and it has navionics maps, i'll use that.

With so many alternative GPS's onboard, it seems to me that dedicated HH GPS's are no longer necessary as a backup!

I think my money is better off spent on beer rather than on yet another GPS. Can anyone think of a reason I should choose another GPS over the beer?

"I have plenty of portable GPS's to put in the oven during an electrical storm"> What does this mean, please?

[terrysandling]

I do not like the beer option, a fools option , but i like the paper chart and the compass option mentioned at the start of this blog by one of our sensible navigators



The rewards of a life lived well is to plant trees under whoes shad you do not expect to sit.,

[hoppy]

Originally Posted by RichandHelen

"I have plenty of portable GPS's to put in the oven during an electrical storm"> What does this mean, please?

In case I'm feeling a bit peckish, I cook them up

My understanding is that in the metal oven, it offers protection for electronic devices if the boat is struck by lightening.

[evm1024]

I do have a friend who was on his way from Hawaii to the Pacific Northwest who experienced a total failure of the entire boats electrical system. alt out, solar out. batteries flat.

His handheld, battery driven GPS and charts got him more than half the way back. For the last 6or 7 days he was using his Sextant.

[nimblemotors]

Just make sure you have a good watertight container to hold the beer for the ditch bag. The last thing you want is salt water in the beer, otherwise you should be good.

[donradcliffe]

Originally Posted by evm1024

I do have a friend who was on his way from Hawaii to the Pacific Northwest who experienced a total failure of the entire boats electrical system. alt out, solar out. batteries flat.

His handheld, battery driven GPS and charts got him more than half the way back. For the last 6or 7 days he was using his Sextant.

Your friend is full of BS or has no business going offshore. If he could use a sextant, there was enough sun to cobble enough of a solar power system together to run a 12v gps.