Finally routed the leg into and out of PYC

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Dec 20, 2010
294
Yankee Condore 21 Halifax
Yesterday afternoon we decided to go over to the boat and take it out ie motor (as you will see why) and chart the buoy marked channel. Unfortunately I had to scale out to get the entire image in one so detail is lost :cry:. I had checked the weather before leaving and saw that the seas were suppose to be building to 2 meters (6ft). I actually did not expect that to be the case right on shore( another dummy moment).

Well filled the water tank checked the bilge and the other checklist items and we where off. I am amazed at the honda ( it finally seems to be running perfectly ). I had the throttle barely past the start location and it pushed us along at nearly 5 knots according to gps.

The area where the text is all jambed together is the contentious one lol as the water depth there is barely 4 feet at low tide and if any waves less. Thankfully it is sand in there.

Anyhow got out to the fantail as I call it and decided that NO WAY as the incoming swell was a meter and building. It might not have been such a big issue had the crest to crest been several boat lengths but in fact was only about 10 feet :eek:. Privateer rode up and thru them well enough but we were still in somewhat protected water :eek: and I could see breakers on the bar out at the mouth of the inlet and to the southwest. I got her turned and we headed back in again. Needless to say she handled much differently with the waves astern :eek:, but not terribly so. Then about a quarter of the way back the wind died out and those pesky little black flies were out every where. We couldn't get away from them :cussing:. We timed our selves going out and it was 55 minutes from the dock out to where we turned around so as figured its about an even hour out the the outside buoys marking the entrance.

OK I made a second jpg showing the inside leg scaled out to show the difference between what the CM-93 chart as well as our 2012 CHS paper chart shows relative to what the 'reality' is. Thankfully we have a swing keel and are not totally dependent upon the tides to come and go:D.

Brina
 

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Squidd

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Sep 26, 2011
890
AMF Alcort Paceship PY26 Washburn Wi. Apostle Islands
So, are you saying the charts are wrong...you were "lucky" in your travels"... or that the overlay doesn't line up with the drawing...?

My "tracking line" has been known to go over the point of an island when I know darn well we were in the water the whole time...:)
 
Dec 20, 2010
294
Yankee Condore 21 Halifax
So, are you saying the charts are wrong...you were "lucky" in your travels"... or that the overlay doesn't line up with the drawing...?

My "tracking line" has been known to go over the point of an island when I know darn well we were in the water the whole time...:)
Hiee,

We had tracking set to every 10 seconds of gps fix. If you look at the inside jpg I put up you will see the track veer east of the supposedly there channel and cross the green ( identified as 'reed' on the chart(s) ). The top of the image is North. There is now exposed sand flats mid way between MY COURSE and the white (deep water) shown on the chart(s) ie going nearly due north. YES the charts are wrong and (after talking to some long time members) have been for quite some time. NOTE the NNE zig is not a channel perse but rather the actual deepest water at low tide. We were within the channel as close to center as I could discern with the locally placed buoys. The buoys have been placed by the local fisherman although some have been known to drift out of place. The tide runs thru here at about 3 knots. And yes the depth as indicated is real as I forgot to wind the keel up on the return trip and it swung back and was bouncing on the bottom until I did wind it up half way lol. The little yellow wave things are OpenCPN icons for sand. The CM-93 charts I am using used the datum off the 2010 CHS charts for this area. CHS = Canadian Hydrological Survey who make all the charts for Canadian waters. Although I understand there are arctic charts made by the Russians that are superior.

What irks me is that my paper chart is identical to this and cost $20.00 for the area and is wrong and could cause a grounding if solely relied upon as again looking at the supposed channel it indicates a depth of 8.9 feet at low median tide when in fact there are exposed sand flats:eek:.

c_witch
 

Squidd

.
Sep 26, 2011
890
AMF Alcort Paceship PY26 Washburn Wi. Apostle Islands
I just blame it on the gps/plotter not being as acurate (or in sync) with the charts as I would like them to be...

ie: The rocks haven't moved, the island is in the same place...the gps just didn't hit the mark as expected and you were lucky you didn't hit the rocks at the top of the chart...

Are you saying the actual "bouys" (hence your path) were out of place...??? (then your lucky) or the bouys kept you safe and the plotter was off...?
 
Feb 26, 2004
23,050
Catalina 34 224 Maple Bay, BC, Canada
I just blame it on the gps/plotter not being as acurate (or in sync) with the charts as I would like them to be......and the plotter was off...?
Uh, nope. The GPS is right, the charts, drawn years ago are incorrect. Think about it. The GPS "knows" where it is, the charts were drawn by hand from manual angles and observations. If anything, the chart needs to be corrected. You don't try to "force" a GPS to "match" a chart, you correct the chart.
 

Squidd

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Sep 26, 2011
890
AMF Alcort Paceship PY26 Washburn Wi. Apostle Islands
I hear you, but it sound backward...

Charts (old charts) have been keeping people off the rocks and out of the shallows for years, with observations, measurments and magnetic readings...

It hasn't been till gps "overlays" put us up in arms as we saw our trail thru the rocks, over the point and way too shallow for our boat...

My stance is the gps isn't "pinpoint" enough to worry about...

Unless you have mil spec, how close are you...? 10 feet..? 10 yards...? 50 yards...??

Middle of the ocean tells me where shore and nearest port is, but I'll prefer charts , bouys and visual observation when I come into the harbor, rather than gps tracking...heck with overlay on chart even if they have their own maps..
 
Dec 20, 2010
294
Yankee Condore 21 Halifax
I just blame it on the gps/plotter not being as acurate (or in sync) with the charts as I would like them to be...

ie: The rocks haven't moved, the island is in the same place...the gps just didn't hit the mark as expected and you were lucky you didn't hit the rocks at the top of the chart...

Are you saying the actual "bouys" (hence your path) were out of place...??? (then your lucky) or the bouys kept you safe and the plotter was off...?
I guess somehow I am not making myself clear. ONE the buoys are for the most part correct. The charts are 'Wrong'. And as the vector enc is derived from the wrong paper chart then it is also 'WRONG'.

If you look at the image showing the red x's and northeast zig into the green note that it shows me traveling into the green and OUT of the CHANNEL. In reality if one continued nearly due north at low tide then you would need wheels under your keel as that area of blue is now exposed sand flats. At high tide we can get thru with our keel up as its about 4 feet deep BUT ONLY AT HIGH TIDE. Someone at CHS has not been doing their homework and simply relying on outdated data for their charts. I simply wonder how many other Canadian charts might fall into the same group!

c_witch
 
Jan 14, 2011
243
tanzer tanzer 28 bathurst nb
the chart can be off a little, but they will always be more accurate then the GPS, reason being that at any point in time your GPS and my GPS or ANY GPS can be off by more then 100ft no matter how you set it. it is the way the system works, the military one are bang on, but i doubt that any civilian has one of those.... No need to get yourself clear, he his right, you should learn your way out by noting line of sight (how two object line up), or marking on a chart where obstruction are, especially if your chart is wrong. You can also call the hydro graphic services and inform them of the discrepancies. Have a good summer and full sail while you can! summer are short!
 
Dec 20, 2010
294
Yankee Condore 21 Halifax
Hiee Mesange,

I think if you look up civilian gps you will find that they are suppose to be accurate to ~ 30 feet. I personally only trust them to about 60 feet or so. During daylight I don't bother with the gps or chart and use the buoys and line of sight. The sole reason for getting a gps track plot was to give us a backup if we ever get caught trying to come back in during darkness,fog or whatever else might impede following a visual course. If you look at the images posted you'll see that the chart is 'Right' for pretty much all the way 'except' for the last half mile or so. Here's another image of the chart that I have airbrushed the area where the exposed sand flats or bar is. Note it is not suppose to be accurate and only illustrative! Anyone following the chart either paper or derived from the paper would find themselves making a softgrounding at anything approaching low tide.

c_witch
 

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Nov 23, 2011
2,023
MacGregor 26D London Ontario Canada
Hi Sea witch. I was out in PEI last week and out on my father in-laws boat out of Stanley Bridge Harbor. I was surprised at the # marker bouys going in and out. (There seemed to be more than in years past.)
I asked why there are so many and was told that the winter storms had changed the sand bars around. They change every year!
It was kind of crazy the path one had to take to get out. At one point there were 3 red bouyes close to the sand bar. Well thats because you only have about 50-60' that's navigable along there! And only 8-12' deep.
I don't think I would trust the paper charts for that area. I think it may be best to mark obstructions on your paper charts.
Have you heard of active captain? https://activecaptain.com/index.php
Check it out, you can put you own markers on it and up load it to help others. Someone may have fixed it all ready.
Good luck.
 
Apr 22, 2011
943
Hunter 27 Pecan Grove, Oriental, NC
the chart can be off a little, but they will always be more accurate then the GPS, reason being that at any point in time your GPS and my GPS or ANY GPS can be off by more then 100ft no matter how you set it. it is the way the system works, the military one are bang on, but i doubt that any civilian has one of those.... No need to get yourself clear, he his right, you should learn your way out by noting line of sight (how two object line up), or marking on a chart where obstruction are, especially if your chart is wrong. You can also call the hydro graphic services and inform them of the discrepancies. Have a good summer and full sail while you can! summer are short!
That was true several years ago when the gps satellite signals were sent out with fairly large position errors. The military receivers had a security code that would correct the errors. But now both military and civilian receivers are seeing the same degree of accuracy. The military can degrade the accuracy during a national emergency. The gps is so accurate that it's data is used to update charts. But it cost money to do this,,, more money more taxes,,, not a popular political move.
 
Jul 28, 2010
914
Boston Whaler Montauk New Orleans
The info on charts definitely needs updating, which is why the Notice to Mariners is published. You'll also see on most charts a degree of variation each year which needs to be considered when plotting your course.

When I go fishing in the marsh down here, I use recent satellite charts and my GPS. The gps charts being older, I often am shown on the gps running over land. Islands have shrunk or sunk, canals and bayous have widened, curves have been cut through, etc.

On the Mississippi river, sand bars come and go very often, and the river pilots rely on the Notice to Mariners and talking to each other to keep abreast of those changes.
 
Nov 9, 2008
1,338
Pearson-O'Day 290 Portland Maine
Brina,

Glad to hear it! This means the transformation has begun. You will be assimilated! You've run aground, been chased back in, spent WAY too much money on repairs and too much time. Now, just drag anchor, get lost in the fog, set down in mud, loose the engine and forget your cooking gear . . . then you will be complete. Wetting yourself because you nearly dump the boat counts for two of those. Hitting an ATON that you didn't see counts as three.

Don
 
Dec 20, 2010
294
Yankee Condore 21 Halifax
Brina,

Glad to hear it! This means the transformation has begun. You will be assimilated! You've run aground, been chased back in, spent WAY too much money on repairs and too much time. Now, just drag anchor, get lost in the fog, set down in mud, loose the engine and forget your cooking gear . . . then you will be complete. Wetting yourself because you nearly dump the boat counts for two of those. Hitting an ATON that you didn't see counts as three.

Don
Hiee Don,

:laugh::laugh:I'm sure I can manage at least one or two of those before the season is over lol.

Brina
 
Oct 25, 2011
576
Island Packet IP31 Lake St. Louis, Montreal
<SNIP>It was kind of crazy the path one had to take to get out. At one point there were 3 red bouyes close to the sand bar. Well thats because you only have about 50-60' that's navigable along there! And only 8-12' deep.
I don't think I would trust the paper charts for that area. I think it may be best to mark obstructions on your paper charts.
<SNIP>
8' - 12' deep? That's 80% of our lake here in Montreal. The other 20% are shallower.

Off topic, I know but I feel better.:D

Matt
 
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