Forums > Sailing General

Computer Navigation

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Created by MAGNESIUM > 9 months ago, 10 Nov 2023
MAGNESIUM
221 posts
10 Nov 2023 4:05AM
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Modern race yachts have a computer set up in their navigation area , I have noticed Romona has a computer screen set up on his yacht .
i am thinking of going open CPN , having not much computer experience and doing all my navigation on the IPhone which is woeful either your fingers are wet and the screen won't work all at the worst appropriate time.
what set up do the modern race boats use ? Will a iPad be a good option ?
would love to hear your ideas.
i want to stay away from subscriptions and be able to check weather etc

julesmoto
NSW, 1569 posts
10 Nov 2023 8:33AM
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MAGNESIUM said..
Modern race yachts have a computer set up in their navigation area , I have noticed Romona has a computer screen set up on his yacht .
i am thinking of going open CPN , having not much computer experience and doing all my navigation on the IPhone which is woeful either your fingers are wet and the screen won't work all at the worst appropriate time.
what set up do the modern race boats use ? Will a iPad be a good option ?
would love to hear your ideas.
i want to stay away from subscriptions and be able to check weather etc





IPad is the worst option because you have to get the expensive SIM card version to get GPS so Navionics works. If you go the tablet route go Android as the GPS chips are separate from the 4g/5g chip so any cheap tablet will run Navionics. Pays to get one with a bright screen tho and also buy a hood as well as a good mount.

Phone still good for an emergency back up but not by itself as inconvenient and can go overboard. Mind you I lost a tablet off the railblaza mount on the binacle in a heavy gust when I stupidly didn't shut the clamp lever on the mount. If you still have the TS with no binacle maybe a tablet on the bulkhead with Velcro tape. I'm going to do that on my Clubman if the software update on my 9 inch Raymarine CP still doesn't facilitate auto routing like the tablet version of Navionics has.
With the tablet route you also have to consider power supply and waterproofing. They are so cheap that you can buy two and have one down below charging and I just use a silicone cover with electrical tape over the cutouts.

Ramona
NSW, 7732 posts
10 Nov 2023 8:43AM
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The PC is one of these running windows 10.
www.ebay.com.au/itm/265807202598?hash=item3de3580926:g:PcMAAOSw2E9i51pI&amdata=enc%3AAQAIAAAA8Nu%2BxxO%2BtBjbx3GePFkNeYXhzt6UfO2uMCn2eSpHde1XZwjE9%2FM2lKnsI8ZIGGfwUQ8d4ASEE%2Fas%2FAkvLij%2FJGMLk6nEz7cSkFXgcNraOr71B8dTiRf8giisngB51%2BuVhuT8Iake%2FCC4i%2FUnitxwGxz7zm69JcEeHeP%2B8kfTjlxfMwbf4PRo0kK%2FxPabi7e7otze5O2gy4zs09a7%2B%2F4sroUuMMNRTeiMMAIWfy9Biz4bAqyAXiN92hvtLRw%2FwSf4nnKRoJr0sBEUTb9wx2q57x4%2F1YLqd7ahABe8rKPPYswDsgRFIhdSh0ySimTgnLZU9A%3D%3D%7Ctkp%3ABFBM-JDr3_Zi
The screen is a 20 inch monitor running in portrait mode. I'm on the East coast so the charts with OpenCPN work better North South. The GPS and AIS come from the VHF radio. When I want to use the internet I connect my mobile phone. The keyboard is one of those floppy $20 roll up ones and I use a normal mouse. The PC was about $100 and the monitor was an old Dell I had laying about. The VHF radio is where most of the money went.

Trek
NSW, 1188 posts
10 Nov 2023 9:15AM
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I suggest get a Windows tablet with a USB port and put OpenCPN on it. Make sure its got a daylight readable screen (bright). They are cheap on sites like Alibaba. Get a Trek Transponder with the NMEA-0183 GPS Data Bluetooth output fitted and the matching wireless dongle for the tablet. Its made especially for OpenCPN.

Then you can use OpenCPN anywhere on the boat wirelessly. At the helm or in bed. Charts for East Coast of Australia $60. The nav data comes to the tablet wirelessly from the Trek Transponders built in GPS which is good one and updates once per second. Ive been using that set up a year now. You get to remotely monitor your bilge and see your boat remotely with HD cameras too.

julesmoto
NSW, 1569 posts
10 Nov 2023 9:35AM
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I have a fixed chart plotter below in the big boat and a fixed chart plotter outside on the bulkhead on the TS. Neither facilitates utilisation in both locations. There are those articulating arms that facilitate swinging the screen from inside to outside through the companionway but that wouldn't help you much if you wanted to view it outside and it was rough. I believe Ramona has indicated that his large below deck screen is visible from the cockpit but again possibly not in rough weather. Treks solution sounds interesting.

If all you want from a tablet is plotting and speed without AIS, depth, wind, autopilot or radar overlay they are great. If you want depth repeater or AIS info I'm not so sure. You can of course receive AIS traffic information via the internet (if you are near coastal reception) if you use Marine Traffic or other sites either on your phone or tethered from phone or 4/5g tablet. Mind you integration of all systems even with a fixed chart plotter is oft reported not to be easy.

Further improvements to my navigation systems are in the too hard/too expensive basket at the moment. Reattaching the mast track and painting the mast of the TS as well as fixing the trailer brakes come first as well as ongoing maintenance of the NS38.

Kankama
NSW, 787 posts
10 Nov 2023 10:23AM
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I run a laptop running OpenCPN but this take a bit of juice. It sits on the cabin table but I can see this from the helm. I like Ramona's computer but we are going the raspberry Pi route.
I like the idea of staying away from touch screens, they are not useful when wet. I am not sure about needing something near the helm, most of the time cruising we are on autopilot, and far away from the helm.

Lazzz
NSW, 902 posts
10 Nov 2023 2:58PM
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IMO you cannot go past having a "proper" chartplotter running Navionics at the helm - They are not cheap but if you are doing any sort of cruising well worth it!!
I also run a similar PC to Ramona as well as a Raspberry Pi4, both with large monitors, at the Nav Station. Both have a separate GPS & have OpenCPN as well as Memory Maps and other navigation software. Google Earth is also handy sometimes with a GPS.
The chartplotter is connected to the Pi4 via NMEA2000 which shows wind, depth, AIS & everything else. I have the second Pi4 monitor at the helm so I can see what is running on the Pi4.

I also have a dedicated "boat" tablet, with Navionics etc, etc, and also can connect to the Pi4 or PC as an extra monitor via wi-fi.

I have a Maiana AIS transponder, which I mainly just have showing on the Chartplotter.
A cheap AIS receiver, which works well, is the dAISy unit: shop.wegmatt.com/products/daisy-ais-receiver which I have as a backup.

My VHS Radio also has AIS & is connected to the Chartplotter with DSC. I don't think I could go back to not having AIS now!!

I had a spare Raspberry Pi3, so I am now in the process of setting up "Home Assistant" on the boat as well!! No need for another monitor or keyboard etc. and does some good things. www.youtube.com/@SmartBoatInnovations

I think Treks system would work well if you wanted to go that way.


Select to expand quote
Kankama said..
I like Ramona's computer but we are going the raspberry Pi route.



Why not run both???

No such thing as having too much redundancy!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Madmouse
427 posts
10 Nov 2023 12:57PM
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I agree about the fixed chartplotter supplemented by an ipad or tablet.
It's hard to find a daylight viewable tablet. An ipad being generally brighter than android.
A decent ipad is about the same price as a bg 9 inch vulcan.
Wifi can connect all the data up.

MAGNESIUM
221 posts
10 Nov 2023 1:30PM
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Madmouse said..
I agree about the fixed chartplotter supplemented by an ipad or tablet.
It's hard to find a daylight viewable tablet. An ipad being generally brighter than android.
A decent ipad is about the same price as a bg 9 inch vulcan.
Wifi can connect all the data up.


Can you recommend one ? Every one I look at eg BCF etc they are not just a chart plotter but has everything else built into it.

MorningBird
NSW, 2699 posts
10 Nov 2023 8:57PM
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The electronics aren't navigating, they are giving you a position and information based on what you entered. **** in, **** out.
You make the decisions on course to steer, hazards and obstacles, time estimates to waypoints or destinations, currents etc.
Do a navigation course if you haven't already.
I'm a trained navigator and have been appalled at sailors who rely on their 'system' without even basic navigation knowledge. IT does not navigate.
A Coastal Skipper course if a good start.

Madmouse
427 posts
10 Nov 2023 7:06PM
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MAGNESIUM said..

Madmouse said..
I agree about the fixed chartplotter supplemented by an ipad or tablet.
It's hard to find a daylight viewable tablet. An ipad being generally brighter than android.
A decent ipad is about the same price as a bg 9 inch vulcan.
Wifi can connect all the data up.



Can you recommend one ? Every one I look at eg BCF etc they are not just a chart plotter but has everything else built into it.


Not sure what you mean by everything else built in but bg, garmin and raymarine are the main brands.
Makes sure it has nmea 2000 and if possible wifi so you can share your data with you phone or a tablet.

Kankama
NSW, 787 posts
11 Nov 2023 8:03AM
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I think I get what Ramona is saying, all I really need is something to help me work out where I am every once in a while. Back in the day, I would have given my eye teeth for a simple lat and long for where I was, then a quick plot on the chart and away we go. There were some pretty scary nights 30 years ago when I couldn't really make anything out in the dark to get a bearing off, lots of bum clenching moments.
A year ago I was racing on a lovely cat. The start boat gave us a distance and bearing to the first mark offshore, but I, and no one else free, could make the electronic nav system work so that we could plot the course. It would have taken me 20 seconds to do it on a chart.
I love the idea of having a paper chart that I pore over, getting everything in my head before we set out and I think this is the best redundancy, along with knowing how to take a bearing, adjust for deviation, use your depth sounder, plot for a safe distance off, look for sea mounts (Jervis and John Young banks I am thinking of you there). More stuff doesn't cover for not knowing how to fully understand the reason behind how safe navigation works. If you get a paper chart and use it, along with compasses, you will understand more fully how a navigator should think. Redundancy is a simple hand held GPS/phone/dongle that spits out a position every 15 minutes. Everything else is icing on the cake.

In many ways for us East coast sailors - sail in daylight and keep Australia on left in winter and on the right in summer. Works pretty well.

Trek
NSW, 1188 posts
11 Nov 2023 9:13AM
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Sailing the east coast of Australia is easy navigating wise, agree with that. But there is a place for electronics in navigating and a chart plotter visible from the helm - in complicated geographic areas. Around the islands of Indonesia you cant just set and forget. Also various Pacific atolls. Even the local channels from Broken Bay to Brisbane Water are problematical - especially at night!

Lenn
NSW, 174 posts
11 Nov 2023 12:43PM
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Select to expand quote
Kankama said..
I think I get what Ramona is saying, all I really need is something to help me work out where I am every once in a while. Back in the day, I would have given my eye teeth for a simple lat and long for where I was, then a quick plot on the chart and away we go. There were some pretty scary nights 30 years ago when I couldn't really make anything out in the dark to get a bearing off, lots of bum clenching moments.
A year ago I was racing on a lovely cat. The start boat gave us a distance and bearing to the first mark offshore, but I, and no one else free, could make the electronic nav system work so that we could plot the course. It would have taken me 20 seconds to do it on a chart.
I love the idea of having a paper chart that I pore over, getting everything in my head before we set out and I think this is the best redundancy, along with knowing how to take a bearing, adjust for deviation, use your depth sounder, plot for a safe distance off, look for sea mounts (Jervis and John Young banks I am thinking of you there). More stuff doesn't cover for not knowing how to fully understand the reason behind how safe navigation works. If you get a paper chart and use it, along with compasses, you will understand more fully how a navigator should think. Redundancy is a simple hand held GPS/phone/dongle that spits out a position every 15 minutes. Everything else is icing on the cake.

In many ways for us East coast sailors - sail in daylight and keep Australia on left in winter and on the right in summer. Works pretty well.


dont suppose you give lessons for the paper based knowledge sharing ... it would be a great skill to have regardless

Kankama
NSW, 787 posts
11 Nov 2023 2:07PM
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Trek said..
Sailing the east coast of Australia is easy navigating wise, agree with that. But there is a place for electronics in navigating and a chart plotter visible from the helm - in complicated geographic areas. Around the islands of Indonesia you cant just set and forget. Also various Pacific atolls. Even the local channels from Broken Bay to Brisbane Water are problematical - especially at night!


Actually it was Morning Bird (not Ramona) who I agree with when he said - do a coastal navigating course

My problem is with people navigating areas they have not been before, thinking that the incredible resolution of the electronic chart, is always linked to the real world. There is a bit of hubris here expecting that the world will conform to our expectations of it. More than one boat has been lost because the skipper did not know about errors and uncertainty and hit a reef where the electronic chart said there was none. Errors get drummed into you when dealing with paper charts but I do navigate off electronic charts and use Open CPN and Navionics, it's just that I only trust them to a point. So having data at my every whim worries me because it may degrade my other skills that I rely on, situational awareness and other methods of navigation. Maybe it is good at the helm, but looking at a screen at night may impair your ability to see a crab pot or a moored boat. It is just because I have been lucky enough to get into trouble because of overconfidence, and then not lose my boat that I am a grouch about more tech. We need more skill as well as more tech. I for one would not like to have newcomers think that navigating up a tricky new channel at night with only the plotter is a safe thing to do. So having one at the helm is problematic - for me - and it is a personal thing.

Using the plotter to follow your track (that you made when coming in) out of a tricky anchorage is fine, but going in somewhere tricky on a Navionics course is something I hope not to do.

woko
NSW, 1757 posts
11 Nov 2023 7:36PM
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Yep what kankama said, & basic coast pilotage using a paper chart is not difficult, all that's required is a few simple tools, obviously an up to date chart of the operating area, a hand bearing compass, a drawing compass will double as a divider, a parallel rule or a plotter or any number of ways of transferring parallel lines ( I used two drawing triangles for a long time) a pencil , sharpener & the most used eraser. Try it it's got a bit of magic

Bananabender
QLD, 1610 posts
11 Nov 2023 10:19PM
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Select to expand quote
Lenn said..


Kankama said..
I think I get what Ramona is saying, all I really need is something to help me work out where I am every once in a while. Back in the day, I would have given my eye teeth for a simple lat and long for where I was, then a quick plot on the chart and away we go. There were some pretty scary nights 30 years ago when I couldn't really make anything out in the dark to get a bearing off, lots of bum clenching moments.
A year ago I was racing on a lovely cat. The start boat gave us a distance and bearing to the first mark offshore, but I, and no one else free, could make the electronic nav system work so that we could plot the course. It would have taken me 20 seconds to do it on a chart.
I love the idea of having a paper chart that I pore over, getting everything in my head before we set out and I think this is the best redundancy, along with knowing how to take a bearing, adjust for deviation, use your depth sounder, plot for a safe distance off, look for sea mounts (Jervis and John Young banks I am thinking of you there). More stuff doesn't cover for not knowing how to fully understand the reason behind how safe navigation works. If you get a paper chart and use it, along with compasses, you will understand more fully how a navigator should think. Redundancy is a simple hand held GPS/phone/dongle that spits out a position every 15 minutes. Everything else is icing on the cake.

In many ways for us East coast sailors - sail in daylight and keep Australia on left in winter and on the right in summer. Works pretty well.




dont suppose you give lessons for the paper based knowledge sharing ... it would be a great skill to have regardless



Invest in the jeff toghill coastal navigation book for $20 . Its a wealth of info.
on how to use paper charts and tools for navigating

Ramona
NSW, 7732 posts
12 Nov 2023 6:48AM
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Select to expand quote
woko said..
Yep what kankama said, & basic coast pilotage using a paper chart is not difficult, all that's required is a few simple tools, obviously an up to date chart of the operating area, a hand bearing compass, a drawing compass will double as a divider, a parallel rule or a plotter or any number of ways of transferring parallel lines ( I used two drawing triangles for a long time) a pencil , sharpener & the most used eraser. Try it it's got a bit of magic


If your just coastal cruising in close just a compass app on your phone will suffice. Just sight along one edge. Check whether it's in True or magnetic of course. There really is no substitute for a large screen plotter though. Screen size about 20 inches is nice.

For many years while I was a fisherman I used the nav programme Seaclear as did all the other operators out of my homeport. It's not as easy to use as OpenCPN and you had to calibrate your own charts. It had the advantage though of making your own charts for close in stuff. I had charts that were only half a mile across. The trawler operators manually plotted the reef edges each day. Eventually you end up with a useful and sometimes valuable chart.

www.sping.com/seaclear/

woko
NSW, 1757 posts
12 Nov 2023 1:15PM
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Agree the phone compass is as good as most hand bearing compass, but it's important on the apple phones at least to turn it it magnetic, apparently there's tiny magnets in the phone to make it possible, true north is not so good, it's probably a bit much to have the magnetic variation to be included. Also apple gps doesn't have digital seconds, it's not a big deal but it can be a trap

Trek
NSW, 1188 posts
12 Nov 2023 1:41PM
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When I sailed around NZ Chart Plotters hadn't been invented. I did it with paper charts and what a pain.

And now having written all the Trek Transponder software to calculate Geofence radius's, great circle sea distances, bearings and headings using different Geodetic Systems at different parts of the Earth in the Northern Hemisphere and Southern (numbers are different because of the oblate spheroid Earth shape) and three different GPS systems GPS USA, Galileo EU and QZSS (Japan) I found the biggest errors in latitude and longitude are from the original charts and/or their original mapping. I even drove Sydney at the time of writing all that software to check various numbers at Trig Stations and found errors.

If the correct Geodetic System is used, and the resolution of the Maths is correct (how many decimal points) location precision by GPS is far more accurate than by paper charts. I found the problem is that the paper chart asserts a rock is at position X but it isnt. Because at the time the chart was made the mappers (who deserve huge credit for what they achieved) didn't have an accurate GPS in 1950. In 2023 we have up to date Google Earth overlays available free and as long as your electronics charts are WGS84 they are great. You can often see shifting sand bars on coastal bars and the real location.

I can't see airline pilots and the military switching to paper charts which says enough to me. The big draw back of Chart Plotters is getting ripped off by the suppliers and the navigators can get dumbed down and might not even know what a nautical mile is. And worse, if the battery fails bad luck. So I keep paper charts but use my OpenCPN Chart Plotter.

woko
NSW, 1757 posts
12 Nov 2023 3:32PM
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Power failure in our little ships is a real possibility unless you have a set up like lazz. And it doesn't have be ship board error, our recent telco outage for instance. I'm not anti ENC in the least bit, paper charts are only of use if you have the basic understanding. How many yachts do recon would be running AUS ENC ?

Achernar
QLD, 395 posts
12 Nov 2023 3:00PM
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Select to expand quote
Trek said..
Because at the time the chart was made the mappers (who deserve huge credit for what they achieved) didn't have an accurate GPS in 1950. In 2023 we have up to date Google Earth overlays available free and as long as your electronics charts are WGS84 they are great. You can often see shifting sand bars on coastal bars and the real location.


I blame Francis Beaufort (1774-1857).

Seriously, WGS84 is used widely by Google and other digital platforms. I'll need to look further into it, but, unlike metric grids (e.g. MGA2020) it is not a fixed grid, and allows for tectonic drift. For example Australia is moving northward at about 69mm per year, which means that "rock at X" might be about 5.0m further north than it was in 1950. WGS84 allows for it, but the metric grids do not.

However, Trek's point is true, the chart-makers of the 50s' did not have the precision we have today.

Achernar
QLD, 395 posts
12 Nov 2023 3:10PM
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I've been reading this thread with interest, as I loaded OpenCPN onto my new laptop. My first impression is that the charts are not as detailed as iSailor on my iPhone with respect to zooming in to the little bays and inlets around Moreton Bay (which, for me, is where the main value lies).

Also, could the brains trust here recommend a GPS puck for plugging into the laptop. There are several comments about the Trek, but is marketed as a boat security system, and it looks expensive for a GPS puck. I'm not looking for a security system.
www.trektransponder.com.au/shop/

Ramona
NSW, 7732 posts
12 Nov 2023 5:54PM
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Select to expand quote
Achernar said..
I've been reading this thread with interest, as I loaded OpenCPN onto my new laptop. My first impression is that the charts are not as detailed as iSailor on my iPhone with respect to zooming in to the little bays and inlets around Moreton Bay (which, for me, is where the main value lies).

Also, could the brains trust here recommend a GPS puck for plugging into the laptop. There are several comments about the Trek, but is marketed as a boat security system, and it looks expensive for a GPS puck. I'm not looking for a security system.
www.trektransponder.com.au/shop/


www.ebay.com.au/itm/201706532025?hash=item2ef6a56cb9:g:GKAAAOSwZ3hjjvxn&amdata=enc%3AAQAIAAAA4Bcvt4kSyvfPo27FG8WbQT96jsdY%2FqBRkdr9I8vTz%2F7nhn%2BUlKswEwpMTAB7%2B80lVhKAU07iWO8LKPy%2F6dGrSnMLYTFVd174MsUwhosVhtEGl80cYgebbScMNcHM87%2B4ZxUgaoJxOsg%2F08%2FeCZrPr84rWGhrrmD15KKM4ne0UvMhOaw0m3Wosu%2FvCv%2FoAqCEa5i5RNifyl5jqTB4F2VcGT7O304HWIgj1pENz0PDBRu4U92TaEWFS6Svhsn1dZiZc7DIAXpsQmab%2BKc%2By%2BpJq%2B18a0aaTmKa5dhgMMs6tPot%7Ctkp%3ABFBMptrgpPhi


Just make sure it's a real one. Ignore the cheap ones! It should be about $75+

MorningBird
NSW, 2699 posts
12 Nov 2023 9:59PM
Thumbs Up

I definitely use electronic aids. My point is I know how to navigate, the risks and errors and procedures to use.
My problem is those who don't know how to navigate and think that looking at a screen will safely get you from A to B. Maybe most of the time it will but you won't know when it won't.
My post is also assuming you are passage making. If you're day sailing from and to your mooring you have different navigation needs than my sort of sailing.

Lenn
NSW, 174 posts
13 Nov 2023 5:19PM
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Select to expand quote
Bananabender said..

Lenn said..



Kankama said..
I think I get what Ramona is saying, all I really need is something to help me work out where I am every once in a while. Back in the day, I would have given my eye teeth for a simple lat and long for where I was, then a quick plot on the chart and away we go. There were some pretty scary nights 30 years ago when I couldn't really make anything out in the dark to get a bearing off, lots of bum clenching moments.
A year ago I was racing on a lovely cat. The start boat gave us a distance and bearing to the first mark offshore, but I, and no one else free, could make the electronic nav system work so that we could plot the course. It would have taken me 20 seconds to do it on a chart.
I love the idea of having a paper chart that I pore over, getting everything in my head before we set out and I think this is the best redundancy, along with knowing how to take a bearing, adjust for deviation, use your depth sounder, plot for a safe distance off, look for sea mounts (Jervis and John Young banks I am thinking of you there). More stuff doesn't cover for not knowing how to fully understand the reason behind how safe navigation works. If you get a paper chart and use it, along with compasses, you will understand more fully how a navigator should think. Redundancy is a simple hand held GPS/phone/dongle that spits out a position every 15 minutes. Everything else is icing on the cake.

In many ways for us East coast sailors - sail in daylight and keep Australia on left in winter and on the right in summer. Works pretty well.





dont suppose you give lessons for the paper based knowledge sharing ... it would be a great skill to have regardless




Invest in the jeff toghill coastal navigation book for $20 . Its a wealth of info.
on how to use paper charts and tools for navigating


done / doing just that, be here in 4 days...

cisco
QLD, 12361 posts
13 Nov 2023 8:14PM
Thumbs Up

Electronic AIDS to navigation are great but there is nothing that beats eyeball navigation. Charts, parallel rules, bearing compass and HB pencils, always remember True Virgins Make Dull Company.

That said, I would not go to sea these days without a GPS unit that gives me a Lat and Long.

Bananabender
QLD, 1610 posts
13 Nov 2023 8:20PM
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Select to expand quote
cisco said..
Electronic AIDS to navigation are great but there is nothing that beats eyeball navigation. Charts, parallel rules, bearing compass and HB pencils, always remember True Virgins Make Dull Company.

That said, I would not go to sea these days without a GPS unit that gives me a Lat and Long.


And the TITS go around the earth laTITude



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"Computer Navigation" started by MAGNESIUM