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Old 26-10-2003, 04:58   #1
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I thought I was wrong...

I thought I was wrong; when I was actually (nearly) right. I’ll never make that mistake again!

Maggie & I were motoring “Auspicious” along the inside channel, between the Northern Shore of Lake Superior and the Barrier Islands (from W. Otter Cove to Shaganash Light) . We departed Otter Cove in light fog, which thickened considerably within the hour.

Though probably under 25 miles, the route is tricky, with several important waypoints. Though Lake Superior is mostly deep water, with steep shorelines; this passage is a little twisty, closely bordered with lots of rock.

Now, at this time, “Auspicious” was still a pretty ‘bare bones’ boat - we had a magnetic compass, and a depth sounder that worked fairly well in shallow water. No Knot-Log, Loran, and GPS was just a pipedream. We piloted by dead reckoning, with Maggie rock-steady on the helm (she can hold a strait compass course for hours, whereas I cannot steer effectively by compass alone), and I doing constant speed/distance calculations (throw a stick overboard and count seconds for 26 Ft. from stem to stern).

So after several hours, blind except for a couple of shadowy glimpses of nearby Island (Lasher, Swede); I am expecting to come upon “The” (un-named) rock between Swede & Shaganash. The fairly high - steep rock should appear about 50 yards to port, and we’‘ll pass close to maintaining a single compass heading Shaganash Light (and an ‘easy’ anchorage). A couple hundred yards to the North-West of us (Starboard) lies a terrible nest of rocks (not shown on the linked chartlet). Piece of cake - I’ve continually calculated dozens of E.P.’s, there’s no wind nor current to introduce leeway, and Maggie unfailingly lays the course I command. Our charts are FULLY & copiously annotated with headings, distances, & etc. from previous fair-weather transits, and we KNOW this passage well.

I’m so confident, that I’m counting down the SECONDS until the rock appears 50 yards of our Port Bow!

The rock appears at exactly my predicted time - but off the Starboard beam. OOPS! It appears that I’ve miscalculated our track (by maybe a couple of degrees), and we’re actually 150 yards South of my E.P. Still no problem - just gooseneck slightly back & right to clear the rock, then reestablish our known heading to Shaganash Light.

Now the ‘sounder’ starts telling us unexpected things (here’s an axiom - unexpected things are seldom good things). The bottom is quickly coming up from the expected 40 feet to less than 10 - then 6 (we draw 5.5'). Oops again! Where in hell are we?

We’re ‘somewhere’ in that previously mentioned ‘nest of rocks’. We spent the next 2 ˝ hours, very slowly sounding our way out of this unfamiliar reef. We were very fortunate in that we caught propitious sightings of several (unknown) rocks & islets, and finally a few glimpses of Shaganash Light, which allowed some rough bearing calculations. I couldn’t begin to describe our track through, and eventually out of, this reef strewn hell - it was a blind meander, accomplished through shear dumb luck, as much as any kind of competence (on my part).

So what happened?

Upon unexpectedly sighting “A” rock to Starboard (expecting to see ‘The” rock to Port), I (mistakenly) concluded that I was South of ‘The’ rock - when, in fact, it turns out that we were slightly North of “The” Rock (& South of “Another” Rk.) - but still within our intended Channel. Had we ‘jogged’ left a little (to Port), we’d have repositioned ourselves “on track” and carried on, without incident, to Shaganash.

Why did I assume that we were completely out of the channel, when it was just a likely that we were merely a little off-centre within the channel? I suspect that, in my heart of hearts, I knew that I was being cavalier, arrogant, and supremely overconfident in my dead reckoning. When I proved (very slightly) wrong, I panicked and totally abandoned my previous assumptions! I then compounded my error by totally abandoning my D.R. assumptions, and attempting radical corrective action.

My (over) confidence was not totally unfounded, so I should have assumed the smallest error, and made the smallest (of two) possible corrections. After all, if you cannot have some measure of unshakable self-confidence in what you are doing (whatever it may be), you shouldn’t be doing it.

I thought I was wrong, when I was (nearly) right - I’ll (try to) never make that mistake again!

For "Chartlet" Go to:
http://offroute.com/previewmap/pv-mappage.asp
Offroute - Map Preview
Then Select:
Lattitude 48 25 56 N
Longitude 88 21 43 W
Then zoom to 10 mi map width - then click "printable:

With (uncharactersitic) humility,
Gord
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Old 30-10-2003, 00:35   #2
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Wow, sounds like a close call to me.

Glad ya made it without a scratch.....I will take good luck any day..

Have done some stuff that could make for a good confessions on these here pages, but ain't gonne tell nuthin....
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Old 05-07-2006, 21:00   #3
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Shear dumb luck you said it not me. Have you ever navigated using just a depth sounder and the fathom lines on a chart. Try that in the fog . Better yet drop the anchor over the side with 15 feet of rode out. See if you hook bottom before you hit it.
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Old 06-07-2006, 03:29   #4
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Sounds as if you had a fortunate "wake-up call". Glad it worked out alright
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Old 06-07-2006, 08:00   #5
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Why is a GPS a pipedream? There are dozens of slightly used choices available for under a hundred bucks.

I am not saying that traditional navigation skills are not important, but the cost benefit analysis of adding a GPS can't be beat. And, you can always not look at it if you want to do it the traditional way! Then if you get into trouble and need assistance, it is right there.
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Old 06-07-2006, 08:04   #6
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The misadventure took place in the 80's, when GPS might cost several thousand dollars.

"... at this time, “Auspicious” was still a pretty ‘bare bones’ boat - we had a magnetic compass, and a depth sounder that worked fairly well in shallow water. No Knot-Log, Loran, and GPS was just a pipedream ..."
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Old 06-07-2006, 08:23   #7
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Quote:
Originally Posted by GordMay
The misadventure took place in the 80's, when GPS might cost several thousand dollars.

"... at this time, “Auspicious” was still a pretty ‘bare bones’ boat - we had a magnetic compass, and a depth sounder that worked fairly well in shallow water. No Knot-Log, Loran, and GPS was just a pipedream ..."
Ok, understood! My apologies...
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Old 06-07-2006, 09:27   #8
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Clearing bearings (and ranges for radar work) are the answer to this problem, provided you have something conspic on the bow/and on the new course.
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Old 06-07-2006, 12:03   #9
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Aloha Gord,
This is the first I've read your account of this incident. Very exciting indeed! I've had these things happen to me before too but I don't think quite so close.
My question is this: Would this have occured if you were using GPS?
As you described the situation GPS/chartplotter would have given you more information but would you have interpreted the rocks that you saw to be the correct rocks?
Hard to go back and rethink the incident I know. My conclusion would be that a person can misinterpret any kind of visual information whether you are using dead reckoning or GPS. I'm glad you missed the rocks and you made it through ok.
I wonder how many groundings have occured because people have trusted their chartplotters more than their visuals. I know a lot of people won't admit it but I know of two incidents where overconfidence in GPS has put people soft aground when all they had to do was trust their visual sightings.
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Old 06-07-2006, 12:20   #10
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Should be looking at the echosounder and comparing that to the chart soundings on the plotter anyway, as that gives a good indication when things are not right.
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Old 06-07-2006, 17:46   #11
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I think traditional navigational techniques are highly over rated. With all the factors working for you or against you - like wind and current and tide - and accurate fixes (not); most positions are "soft" at best. I'm not saying don't use them, I'm not; but what I am saying is that getting an accurate fix, taking into account all the variables, isn't that exact some of the time unless you are in area with lots of referent points.

Anything that can add to the picture like radar, chart plotters, depth sounders is an asset - though GPS was available to you at the time. When I was in the Navy as an officer, I saw lots of navigational errors made - and caught once loran and radio direction finders were factored in.

I have a scar over my left eye because my buddy and his wife were practising night navigation, except the two lights they took the fix off of, weren't the correct two lights; we discovered that after we hit the shoal.
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Old 06-07-2006, 19:14   #12
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Aloha RSN,
I hope you didn't get the idea that I don't like GPS. I think its the greatest and will incorporate that with a laptop and my Capn Voyager when I'm ready to do some more serious navigation. (now I can always see where I'm going pretty much all the time.) I just want to keep my celestial and coastal navigation skills up to date as well and not become so dependent and confident on GPS to the exclusion of common sense.
You have those backup skills that you learned in the Navy. I'll bet you use them occasionally.
Regards, --John--
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Old 06-07-2006, 19:45   #13
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No, I didn't think you were anti-GPS. Its just I hear so much about people "navigating" using traditional techniques as though they were the way to go. No one in this thread is implied that; I'm just reacting to items I read in the mags, etc. Having used the traditional methods, I know they just weren't that accurate, there are tens of thousands of ship wrecks to back me up.

Heck my Catalina 27 has more sophisticated electronics on it now than the destroyer I served on in the Canadian Navy in the early and mid-seventies, in terms of accuracy. Back then we had a rolling table about 2/3's the size of a ping pong table, bearings would come back from the radar guy and these bearings would be plotted, then by drawing lines on the bearings as the paper on the table moved, in relation to our speed and theirs, you could get a bearing line on other vessels. This often took two or more guys.

Now I look at the tail on my colour JRC 1800 radar and it gives me the bearing right away. About the only thing that was more sophisticated than on my boat was communications on my old destroyer.

I think with the "traditional" methods, its easy to beat yourself up because your work isn't accurate, with the implication that others are accurate. I guess I'm saying that unless you were and are a dedicated navigator, most navigating wasn't that accurate.

Take the traditional admonition that if the fog comes in rely on dead reckoning, this will help you get to your anchorage. Well its sounds simple until you factor in wind, tide and current. So one book I read said if you are heading out and caught in the fog, take your reciprocal course and with the use of dead reckoning, work your way back to port. Yeah right.
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Old 07-07-2006, 12:50   #14
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RSN,
Good points. Dead reckoning almost got me on the rocks in a fog twice so I welcome radar and chartplotters. Maybe that's why the "dead" is in the dead reckoning? Anyway, my Destroyer/Cruiser days were from '63 to '88 and I remember a lot about the old ways of navigating even though I was stuck in an office most the time. I did a fair share of bridge/CIC watches. I truly am a believer in the new technology. Much better than the old stuff.
Regards, --John--
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Old 09-07-2006, 11:16   #15
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I think the companies now need to work on more "bullet" proof electronics; ones that aren't as fragile as todays can be. By this I mean more rugged chart plotters, fish finders and radar screens.
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