Acutal use of celestial navigation prior to the GPS era

slug zitski

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A vital skill with celestial is the ability to stand offshore for days or weeks waiting to enter a fog-bound port. Also creeping along on soundings. 
This is the secret .. timing landfall and patience 

i can remember several landfalls with primitive navigation having to hove to and Waite until things made sense

bermuda is the classic, the Gulf Stream is so unpredictable that all you knew was that you were 50 or so miles NE of bermuda .. you then had to stop , look for airplanes , ships , clouds …  monitor for the radio beacon then  identify the reef  

Mt Pico in the Azores was another …stay south of Horta , slow down and Waite for things to make sense with bearings  on pico 

 

sugarbird

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Caribbean
In the late 70's and early 80's we were routinely doing longish offshore passages several times a year. You used everything available. Maintained a detailed log and Dead Reckoning plot, RDF, and sun sights, and you'd wind up with a circle on a paper chart, that you felt pretty comfortable you were probably somewhere inside. Had a nice Plath sextant, used a Zenith Transoceanic shortwave receiver to pick up the time signal and set the chronometer. Bought the Tamaya NC-77 when it first came out, and that made working up positions easier, but didn't improve the accuracy (except for math errors), which depends of the sight itself. When we brought aboard a Loran C receiver I continued the same process above, then turned on the C to see how far off I was. But it's always (and still) a good idea to be a little skeptical of where your instruments and plots tell you that you are, especially when in the vicinity of hazards. Just yesterday my GPS/chartplotter showed us moving across dry land, at least 75 yards from our actual position.

image.png

 

accnick

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I used to give pre-race talks on navigation for new offshore sailors in pre-GPS days. I would describe offshore navigation to them as a brute-force process: use every tool in your toolbox to figure out where you are.

Younger sailors here will probably not remember loran charts with loran time difference curves plotted on them. These were basically electronic LOPs that you used for plotting exactly like the LOPs you derived from celestial navigation.

Remember one of the first "consumer" Loran-C units with the capability to calculate position rather than give you LOPs? I believe it was the Texas Instruments TI-2000, and it cost about $2000 US in 1980.

I thought I had died and gone to heaven racing on a boat with one of those for the first time around 1980.

 

estarzinger

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It is actually quite surprising what you can do navigationally with limited information.

These guys (a pair of young french guys . . . of course) made a 27 day crossing from france to Guadeloupe, and made accurate landfall on Guadeloupe (the intended destination) with no navigation instruments (no compass, no watches, no charts maps or documents, obviously no radio or sextant).

The method was to sail SW very roughly by the sun direction, until they get to the latitude of Guadeloupe, which they would know because one particular constellation would be just above the horizon, and then head west running down the latitude. So, they really just needed one precision piece of information to make it (the constellation).  Ofc harder than it sounds to pull off in practice.

There have been a bunch of other 'no instrument' voyages (not to mention the polynesians), including a rtw, but I always found this one particularly interesting because of their precision landfall and simple direct technique.

--------------------------------------------

sort of funny - a bunch of us old guys going on about how hard it was when we had to walk to school in the snow in our bare feet uphill both ways :)

 
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Elegua

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As a teenager, I kind of caught the end of it.  I had the chance to sail with a crusty old couple who kept a surprisingly accurate DR, did 3 sights a day weather depending, were very, very, picky about watch keeping habits; very, very picky about how everything on the boat got done (do it wrong, you heard about it), were the worst cooks I ever sailed with and probably drank a bit too much.  We used a leadline to confirm the bottom composition, and RDF and hand bearing compass to run LOPs.  The engine was unreliable, so everything was done under sail. Unfortunately, I was too busy being a teenager that knew everything to really appreciate what I was being shown.  

 
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Liquid

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I did the '84 Newport-Bermuda race, no GPS. Our naviguessor got us there perfectly.

As we approach the finish, we hear a boat hail the RC to let them know they were withdrawing from the race as they were actually 50+ miles south of Bermuda........

How many times do you think that naviguessor rechecked his last calcs before going up on deck?

 
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estarzinger

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as they were actually 50+ miles south of Bermuda........
One time we were approaching Bermuda from the north, saw a sail on the horizon, who turned to close with us.  He knew he was somewhere close to bermuda but had been circling around for 3 days and just could not find it.  We told him to just follow us.  But apparently we were too slow because that night he charged off ahead.  We got in the next morning (had been timing it for that) and he then did not get in for another 3 days lol - apparently missed the island over night (which puzzled me because there are or were some pretty decent lights, but single hander/fatigued things happen I guess.).

 

accnick

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I did the '84 Newport-Bermuda race, no GPS. Our naviguessor got us there perfectly.

As we approach the finish, we hear a boat hail the RC to let them know they were withdrawing from the race as they were actually 50+ miles south of Bermuda........

How many times do you think that naviguessor rechecked his last calcs before going up on deck?
1984 was very rough for about half the race. We seemed to go upwind in 25-35 knots of wind forever, as I recall, particularly in the Gulf Stream. The boat I raced on that year had a lot of issues--seasickness, torn sails, and an exploding holding tank being the primary ones. 

It is funny in hindsight, but was anything but funny at the time. One the plus side, I made one good friend on that trip that I have since raced with for thousands of miles.

 

accnick

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I did the '84 Newport-Bermuda race, no GPS. Our naviguessor got us there perfectly.

As we approach the finish, we hear a boat hail the RC to let them know they were withdrawing from the race as they were actually 50+ miles south of Bermuda........

How many times do you think that naviguessor rechecked his last calcs before going up on deck?
1984 was pre-GPS for civilians by a number of years.

 

Liquid

Super Anarchist
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1984 was very rough for about half the race. We seemed to go upwind in 25-35 knots of wind forever, as I recall, particularly in the Gulf Stream. The boat I raced on that year had a lot of issues--seasickness, torn sails, and an exploding holding tank being the primary ones. 
That's the one...

I swear our navi never left the nav station for 2+ days but to take sightings, lots of sun shots. He never got seasick - the old bastard!

5 days to get there, half upwind in 25-35, in a C&C 40 with I think 11 onboard, severely clogged head, leaking diesel tank, shredded jibs, half the crew seasick... However, 4 glorious days to get home on a fair weather, single tack with only 5 onboard - ahhhhhhh.

I was only 18 but that was the first and only time I've been seasick. Wow, being seasick just fucking sucks! I remember puking over a main winch while grinding thru a tack! Also, square waves, no chance of staying dry, no food, no sleep as I had to pin myself in the bunk, pissing in the cockpit, trying to get the #3 jib down now that it's in 2, soon to be 3 pieces- at 2AM, then looking up and seeing a clear, Milky Way filled sky above!

I did hear on the docks that that race dusted so many veterans with seasickness that it was cool to admit it...

 

Steam Flyer

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Disclaimer, I've never made an ocean passage as -the- primary navigator. But did navigate before GPS but after the advent of cheap good timepieces (Seiko crystal) and a few times had better fixes than the real nav guy.

The hard part is knowing what corrections to add and which ones to subtract, and if you're working in minutes and seconds, to get that to come out right. I'm the type of guy that triple-checks everything, and I've seen people trip up going from minutes and decimal seconds, to decimal minutes. Etc etc.

I enjoy the physical skill of getting a good sight at sea. It's trickier than the books let on. And you have to practice hacking the seconds, unless you have a helper which I never did.

Remember, the old fashioned nav work includes updating your ded reckoning which we always did 4 times a day at a minimum; this is overkill at sea but it also keeps a healthy routine. When I first did passages with family and family friends, boats didn't have depth sounders either!

- DSK

 

slug zitski

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That's the one...

I swear our navi never left the nav station for 2+ days but to take sightings, lots of sun shots. He never got seasick - the old bastard!

5 days to get there, half upwind in 25-35, in a C&C 40 with I think 11 onboard, severely clogged head, leaking diesel tank, shredded jibs, half the crew seasick... However, 4 glorious days to get home on a fair weather, single tack with only 5 onboard - ahhhhhhh.

I was only 18 but that was the first and only time I've been seasick. Wow, being seasick just fucking sucks! I remember puking over a main winch while grinding thru a tack! Also, square waves, no chance of staying dry, no food, no sleep as I had to pin myself in the bunk, pissing in the cockpit, trying to get the #3 jib down now that it's in 2, soon to be 3 pieces- at 2AM, then looking up and seeing a clear, Milky Way filled sky above!

I did hear on the docks that that race dusted so many veterans with seasickness that it was cool to admit it...
We won our class in that race 

yacht Full Cry 

luck

the big New York yacht club guys on board all got seasick 

me and my mate were the only ones left sailing 

As the sun was setting the fleet tacked to starboard , we shout down below … DO WE TACK ? big guys were all incapacitated, projectile vomiting … no answer …so we continued on port tack all night … got almost one hundred miles to the west of rhumb  line   …. 
good luck move , sailed into a huge header , when we tacked the next day  we were lifted up to  layline 

won class and the governors trophy …boat that won its class by the largest margin 

good to be lucky 

 
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Bristol-Cruiser

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This is the secret .. timing landfall and patience 

i can remember several landfalls with primitive navigation having to hove to and Waite until things made sense

bermuda is the classic, the Gulf Stream is so unpredictable that all you knew was that you were 50 or so miles NE of bermuda .. you then had to stop , look for airplanes , ships , clouds …  monitor for the radio beacon then  identify the reef  

Mt Pico in the Azores was another …stay south of Horta , slow down and Waite for things to make sense with bearings  on pico 
It was very poor planning to put the reef on the NW side of Bermuda, the direction from which most people are coming. I remember on our first (celestial nav) trip from NYC to Bermuda having three cruise ships overtake us, exactly on our course, about four days out (slowish boat). Made me feel a lot better about my naviguessing.

 

longy

Overlord of Anarchy
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San Diego
First 5 deliveries HI to the west coast I did were all solely celestial. Like the Polynesians, you got good at looking for signs of closing the coast. Kelp, water color change, smell, smog, all got factored in. Just ran noon sights until 2 - 3 days off the coast, no need to be any more accurate than that, theirs nothing out there to worry about. If you took sights/times approaching LAN, and a few after your peak altitude, you can plot them out and verify your accuracy (or extrapolate the LAN) as the curve of the altitude is a flat topped bell curve.

    One trip HI to Seattle we made landfall (?? very, very thick fog) to the entrance of the Straits after 5 days of no clear sky, morning/noon/night. Quite uncertain of our position.  Finally heard a fog bouy off in the distance - motored over to it to identify it & fix our position. It was not on the chart, not in the coast pilot, not in the notices to mariners we had diligently written down before departing. Got on the VHF & called up the US Coast Gaurd - they could not identify it, tried telling us we weren't timing the horn signal right. So we held the mic out the hatch so they could time it. After 30 minutes or so the Canadian CG came up & said they had just replaced that bouy, the notice hadn't gone out yet. We were close to the coast of Victoria Is, not the South (US) coast we were aiming at

 
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