GPS as the Sole Means of Navigation.

[Crimea Cruiser]

Originally Posted by boatman61

Its amazing how many folk can't judge depth in clear waters by eye and proven old laws like navigating reefs should be done pre noon.. a quaint ancient custom/taboo...

Damn Boatman! We are showing our age aren't we! ))) Been thinking for a while we need a sage advice, practices and customs thread here. Get some folks thinking back to the basics of navigating and sailing.

[Hudson Force]

Originally Posted by goboatingnow

George , the colonials are acting uppity again, send in the gunboats

dave

Thanks, I needed a good laugh at sunset. What are you doing up so late!

[boatman61]

Originally Posted by Crimea Cruiser

Damn Boatman! We are showing our age aren't we! ))) Been thinking for a while we need a sage advice, practices and customs thread here. Get some folks thinking back to the basics of navigating and sailing.

Ahahahhahaaa... your only as old as you feel...
and I feel I could do it all again...

[goboatingnow]

Originally Posted by CaptForce

Thanks, I needed a good laugh at sunset. What are you doing up so late!

mom, lets me stay up late on saturdays after bath night.!!!!

dave

[Rakuflames]

Originally Posted by Jim Cate

Raku, while this sounds good if you say it fast, "double-checking with the locals" is not always an option for those who cruise to distant destinations. Why? Well, there often are no locals, or they may not speak your language, or they may not really like yotties and decline to divulge local knowledge or you may arrive while they are busy casting virgins into the volcano... lots of reasons!

Thus, cruisers must be able to cope on their own by whatever means are available to them... charts, e-charts, mud maps garnered from other yotties, depth sounders, cruising guides, eyeballs, experience, and if available, local knowledge.

And in fact, local knowledge often comes from a grinning local paddling a dugout canoe which draws less than a foot. We've learned to NEVER trust locals for depth advice...

Cheers,

Jim

Fascinating. I'm thinking Plan B would be someone hoisted up the mast with good Polaroids.

[jackdale]

Originally Posted by boatman61

Its amazing how many folk can't judge depth in clear waters by eye and proven old laws like navigating reefs should be done pre noon.. a quaint ancient custom/taboo

I still use a lead line in our very unclear water in the PNW to verify depths especially under the rudder when tied stern-to.

[charliehows]

Originally Posted by Rakuflames

Fascinating. I'm thinking Plan B would be someone hoisted up the mast with good Polaroids.

worked for capt. cook, sans polaroids.

[conachair]

Originally Posted by Rakuflames

Fascinating. I'm thinking Plan B would be someone hoisted up the mast with good Polaroids.

Personally I've found Google earth satellite imagery very useful in certain situations.
GE2KAP will convert images for use in opencpn.

http://yachtvalhalla.net/navigation/...geoverlays.htm

Think I would always constantly double check the GPS position looks OK but so far it has been very accurate, even when digital and presumably paper charts are out.

[Rakuflames]

Originally Posted by conachair

Personally I've found Google earth satellite imagery very useful in certain situations.
GE2KAP will convert images for use in opencpn.

Create KAP

Think I would always constantly double check the GPS position looks OK but so far it has been very accurate, even when digital and presumably paper charts are out.

I thought of that too, but isn't that kind of internet connection expensive out on the big wide blue? But two recent printouts of the area -- one in the hand of the guy up the mast (hey, it isn't going to be me!) and one in the skipper's for easy reference ...

[conachair]

Originally Posted by Rakuflames

I thought of that too, but isn't that kind of internet connection expensive out on the big wide blue? But two recent printouts of the area -- one in the hand of the guy up the mast (hey, it isn't going to be me!) and one in the skipper's for easy reference ...

Rare that there isn't some wifi around, even if it means buying a happy hour cocktail. Even if you don't go the full ge2kap route, zooming into the next few anchorages you might end up on Google earth stores the imagery in their cache so it's available off line. Plenty strings to the bow is a good thing

[Blue Crab]

Apologies if this has been discussed:

Students from the University of Texas gave us another reason not to mess with the Lone Star state: they'll hack your yacht. In cooperation with a luxury boat's owners, the Longhorns manipulated their $80 million vessel's nav system, covertly guiding it off-course -- all without the crew ever suspecting foul play. By transmitting spoofed global positioning system signals toward the craft, the students tricked its drivers into correcting a non-existent, three-degree course deviation, thus leading them off track. With their work done, the Texans believe this shows exactly how easy it is to exploit civil-band GPS signals. College kids may have conned the helm this time, but it isn't too far-fetched to think pirates could do the same. Our timbers are shivering just thinking about it.

University of Texas students send yacht off-course with GPS exploit (video)

[boatman61]

Originally Posted by conachair

Rare that there isn't some wifi around, even if it means buying a happy hour cocktail. Even if you don't go the full ge2kap route, zooming into the next few anchorages you might end up on Google earth stores the imagery in their cache so it's available off line. Plenty strings to the bow is a good thing

LMAO... remember someone confidently sailing into a harbour with a Google Earth overlay.... only to find a Commercial shipping port had been constructed in the 2yrs since the 'Snapshot'...

[David_Old_Jersey]

One thing not mention are Pilotage Notes, own.

If coming in somewhere new or tricky I study up from whatever sources of info I have, (Charts / Pilot Books / Internet! / Chartplotter!) and then distil the plan and any relevant info (on expected marks and bearings etc) into a form I can easily understand and can use on deck / at the helm.......for me that means paper, for others electronic - it's whatever works best for "you", especially at times of pressure.

Whilst I do like a pencil for navigation, nonetheless am looking forward to when Chartplotters and gizmos go head up display (via Glasses?) so can both look out the window and see what the Gizmo thinks I am looking at!

[conachair]

Originally Posted by boatman61

LMAO... remember someone confidently sailing into a harbour with a Google Earth overlay.... only to find a Commercial shipping port had been constructed in the 2yrs since the 'Snapshot'...

Was it on the charts?

Done the same going into a port in Brazil, new suspension bridge wasn't on any charts. Or Google earth. Made it onto Google not long after but might still be missing from the charts down there.

But don't dismiss Google earth too quickly, sometimes as another source of info it comes in very handy.

[boatman61]

Originally Posted by conachair

Was it on the charts?

Done the same going into a port in Brazil, new suspension bridge wasn't on any charts. Or Google earth. Made it onto Google not long after but might still be missing from the charts down there.

But don't dismiss Google earth too quickly, sometimes as another source of info it comes in very handy.

Would have been if he'd been an active 'Updater'... logical if you think about it... else no ships would go there....