Traditional or digital navigation - which is safer?

[Group9]

Originally Posted by bstronger

This is simple. BOTH. An experienced navigator knows he needs at least two independent data sources. Bring your gps enabled iPad anywhere you go to back up your Garmin and your Coastal Explore on a bullet prove laptop.

Yeah, that's what I was thinking. Who says you have to pick and use one way exclusively. Electronic and paper charts is how I roll! (Probably, partly because there wasn't really any type of economically feasible electronic navigation when I started going places in boats).

I didn't get my first GPS until like 96 or so, (It was a Magellan 310, whenever those came out). All it would do was give you lat-lons, and a straight as the crow flies course to a particular point, with no clue what was in between you and that point (we still used paper charts for that back then).

I can remember sailing to the Bahamas in the 80's on a boat with a Loran, that was sometimes several miles off (because the TD lines were almost parallel at times!). Loran back then, had great repeatability, but often wasn't that accurate in getting you to a point in the first place! But, I couldn't afford one, so it didn't matter!

A plan without a backup plan, is really a hope and a prayer, more than a plan!

[vikingwoman]

Originally Posted by RichMac

I started navigating with paper charts and celestial, there was no choice then.
Watch "Yacht Navigation - how to be safe", https://youtu.be/iTQxLhp45lg

I really like the accuracy and ease of modern digital navigation, but many people still prefer the old traditional methods. Do some sailors still navigate with safety using just paper chart plotting and a sextant?
Or have we all switched off our navigation brains, and been seduced by the convenience of GPS?

Paper charts, paper pilots,249 nautical almanac , compass, time and sextant are our main NUMBER ONE!

Don't get too lazy using your skills!

Not affected by lightning, salt water or failure of complicated systems. Electronic is our backup and for frequent logging if it works.

Don't waist too much time on electronics. Paint , maintain and keep the ocean out of the boat.

Happy voyaging !

Charla

[Paul L]

Originally Posted by vikingwoman

Paper charts, paper pilots,249 nautical almanac , compass, time and sextant are our main NUMBER ONE!

Don't get too lazy using your skills!

Not affected by lightning, salt water or failure of complicated systems. Electronic is our backup and for frequent logging if it works.

Don't waist too much time on electronics. Paint , maintain and keep the ocean out of the boat.

Happy voyaging !

Charla

Actually magnetic compasses are effected by lightning strikes.

[vikingwoman]

Hi Paul,
Not is a steel boat.

[Jim Cate]

Originally Posted by vikingwoman

Paper charts, paper pilots,249 nautical almanac , compass, time and sextant are our main NUMBER ONE!

Don't get too lazy using your skills!

Not affected by lightning, salt water or failure of complicated systems. Electronic is our backup and for frequent logging if it works.

Don't waist too much time on electronics. Paint , maintain and keep the ocean out of the boat.

Happy voyaging !

Charla

On the contrary, paper charts and pilots and any paper based materials are indeed affected by salt water. Paper charts cam be blown overboard, too..

And sextant mirrors are degraded by that corrosive liquid, and sextants can be rendered useless by dropping.

And mechanical chronometers are kinda sensitive to shock and immersion too.

I don't think that things are quite as clear cut as you propose, Charla. Both traditional and modern nav equipment have their failure modes and require backups. And yes, in the old days I carried a cheap backup sextant... and used a HP-41 calculator with a "nav-pack" to reduce sights with 249 and an almanac as backup.

Jim

[vikingwoman]

Hi Jim,
Just looked at my trusty HP 41CV with nav pack ; yes it is a bit of a cheat from the long way. I just love sailing because of the past skills and following those sailors of the past.

Yes charts can easily be lost or damaged if not kept in a vinyl zipped chart and grommet for lanyard attached in the cockpit. A quartz chronometer or several with wwv to check. So Iam not completely Old School.

It is a personal choice how dependent you are on the computer age. And we do have our fair share. With my husband a USN jet pilot he just loves all the gadgets..

We are off on a world trip in 35 days weather window permitting.

Charla

Fair Winds

[Jim Cate]

Just looked at my trusty HP 41CV with nav pack ; yes it is a bit of a cheat from the long way. I just love sailing because of the past skills and following those sailors of the past.

This got me to thinking, Charla... I bought my HP41 in 1983 and it still works as new! Hard to get that kind of reliability in electronics these days!

To be honest, by the time we were phasing out of celestial I was using a great DOS based program on an early Toshiba (dual floppies). IIRC it was called PCNav, and it not only did the sight reductions but would average several sights, throw out the outliers and produce a fix from a round of stars. Plus a star ID feature which meant that if one's DR was at all good it would identify the star in use. Very handy when shooting through holes in cloud cover when ID was difficult.

Using such "modern" aides meant that I was more likely to take multiple sightings and that there were fewer errors... generally improved my accuracy, but still shooting from a height of eye of ~7 feet from a 30 foot boat made horizons kinda vague.

Ahhh, the good ole days! (Not)

Hope you and your jet jockey enjoy your cruising as much as Ann and I have.

Jim

[Cpt Pat]

Originally Posted by Paul L

Actually magnetic compasses are effected by lightning strikes.

I keep my hand sighting compass, which is my last ditch backup compass, in a small steel box when it's not hanging around my neck. If I encounter a thunderstorm, it and essential portable electronics go in the microwave (I pull the AC plug just in case I become more stupid than usual).

Sitting square on the midline at the stern, I sight the mast base for a sightline. It's accurate to within +/- 2 degrees, provided I remove my steel-framed glasses.

[Cpt Pat]

Originally Posted by Jim Cate

This got me to thinking, Charla... I bought my HP41 in 1983 and it still works as new! Hard to get that kind of reliability in electronics these days!

And if you look on E-bay, HP41s are selling at the same or higher price than back in the 1980s.

[Terry107]

With the introduction of the European GPS system Gallleo ,the Russian Glosnas system, India have developed a system and Japan has the Zenith system surely if the American GPS system ever goes down there will be plenty of digital backups.Having said that, evoking the doomsday scenario maybe a paper chart old and outdated would still be any to have in the chart draw together with a sextant.If that does not reassure you, maybe its time to give up the sailing bug!!

[Paul L]

Originally Posted by vikingwoman

Hi Paul,
Not is a steel boat.

And what difference does that make. It in fact makes keeping a magnetic compass calibrated far more difficult, including after a lightning strike.

[chrisr]

Originally Posted by Cpt Pat

And if you look on E-bay, HP41s are selling at the same or higher price than back in the 1980s.

if we are going retro, then the HP41 should have a back-up - or folk should learn how to work out celestial sights long hand - like i did. back in the day we use to look very sideways at the various electronic sight calculators...not to be used / trusted

if you are going to get carried away about sextants and paper charts, then you need to go the whole hog. how many boats carry norie's tables these days ?

how many folk here know how to use them ?

cheers,

[jtsailjt]

Originally Posted by vikingwoman

Paper charts, paper pilots,249 nautical almanac , compass, time and sextant are our main NUMBER ONE!

Don't get too lazy using your skills!

Not affected by lightning, salt water or failure of complicated systems. Electronic is our backup and for frequent logging if it works.

Don't waist too much time on electronics. Paint , maintain and keep the ocean out of the boat.

Happy voyaging !

Charla

Sounds like you have a good work ethic regarding keeping up your skills but the object of this game is to know just where we are at all times, no extra points for working harder at it than the other guy. In fact, by keeping track of where you are as effortlessly as possible, you free yourself up to notice other things outside the boat or to attend to other boat chores or sail trim or....

You list several factors that can negatively impact gps chartplotters including lightening strikes but didn’t mention that an overcast sky turns a sextant into just an awkwardly shaped paperweight. Im sure you’ll agree that overcast skies are significantly more common than are lightening strikes. Also, if your boat does ever take a direct hit from lightening , it might not much matter what method of navigation you were using if you happen to be in its path or if it blows a hole in the bottom of your boat. In fact, you may not even notice that your chartplotter was just fried because at that point navigation will be so far down your list of priorities.

[El Pinguino]

Originally Posted by jtsailjt

........ an overcast sky turns a sextant into just an awkwardly shaped paperweight. Im sure you’ll agree that overcast skies are significantly more common than are lightening strikes. ...........

That is where other traditional skills come into play..... knowing how to work out a DR and an EP..... and - when course changes are caused by wind shifts - knowing how to do a 'day's work'.

I know of at least two cases... well before GPS etc etc .... where ships have been brought safe to land on a schoolboy's atlas

1968: Fire on ocean liner SS Gothic in South Pacific | Maritime Radio

Another involved an Orient Liner in WW2....

[Cpt Pat]

Originally Posted by chrisr

if we are going retro, then the HP41 should have a back-up - or folk should learn how to work out celestial sights long hand - like i did. back in the day we use to look very sideways at the various electronic sight calculators...not to be used / trusted

if you are going to get carried away about sextants and paper charts, then you need to go the whole hog. how many boats carry norie's tables these days ?

how many folk here know how to use them ?

cheers,

I've always done it the "retro" way: paper and pencil. If you have the tables, noon sites are just simple arithmetic. Nothing more than addition and subtraction.

I buy a fresh almanac every year. You can also download the tables for free, but that defeats the purpose. I assume that, if I'm doing sights for real, nothing electronic is working.