At the confessional

[MichaelD]

This is by way of confession, and hopefully some learning. On August 27th of this year I hit a plainly marked reef. At least it's plainly marked in hindsight. It was completely submerged when I hit it.

On the south end of Vancouver Island, near Oak Bay SE of VIctoria, is Muoat Reef. I was travelling through Enterprise Channel enroute to Victoria on an unplanned "shortcut"; i.e., I had not thoroughly vetted the route in advance. The problem is easy to see in this Navionics view sitting at my desk, but at the time, in the clutter that can happen on chartplotters, it looked to me like I had a clear path and I did not see that there was a Cardinal Buoy showing south of danger.

So, motoring along I noticed a hundred or so yards off my port bow, a funny looking spherical, grey grungy buoy, very hard to see against background of Trial Island. "Huh", thinks I, "what's that?" It's now approaching my beam as I take the glasses and look and see "oh, it's a bit yellow, and it has two black triangles above pointing down which means it's south of danger.....just like it's south of me...." As the wheels spin I grab for the throttles/shifters just as a loud bang occurs and the boat levitates a foot or so, followed by some metallic clatter, and then I'm free.

There followed a very tense couple hours as we assessed damage, talked to the Canadian Coast Guard, found a yard that would open for us on Saturday about 20 miles away, and were able to go under our own reduced power to a haul out. The support from the Coast Guard and from Vector Marine Services in Tsehum Harbor along with a few other marinas and Vessel Assist that got us the yard contact, were tremendously comforting and helpful.

The lesson learned is obvious; but, it's worth noting that important ATONs may not always be easy to see or look like you might think they should. This one was definitely not up to the task...nor was our skipper.

 

[AlaskaProf]

This is by way of confession, I was travelling through Enterprise Channel enroute to Victoria on an unplanned "shortcut"; i.e.,

Your admirable contrition is noted and you obviously need no further chastisement nor instruction, but the story speaks to me on a couple points:


1. In perhaps a couple dozen passages to Victoria or the West Coast in the last forty years, I've always viewed that channel with unease, and have gone around the outside of Trial Island, even while watching other vessels taking the obvious shortcut. Just me, I guess.


2. I simply can't use chart overlays on a radar display. Thirty years of air traffic control demanded that radar displays be optimized for target presentation. While mapping is needed for the ATC purpose, they are a minimal number of dim symbols and line segments with the supporting info presented elsewhere. In boating I've always operated separate displays side-by-side and had no difficulty doing the "overlay" in my head.

 

[MichaelD]

Great point about splitting radar and chart displays. Thanks.

 

[Jmarsh203]

I’m with alaskaprof. I work on tow boats and we do not overlay on top of charts ever. In our world charts are used as reference of where we are and where we should not be. Radar is our eyes in real time when we can’t use our actual eyes. Trying to combine the two makes no sense since they do two different very important jobs. Just fancy gimmicks that will get you into trouble by doing exactly what you said it did clutter things up when clarity is what’s important.

 

[DDW]

A very good use of radar overlay is to confirm that the GPS coordinate system in use matches the rocks actually seen. Not an issue near Victoria perhaps, but there are more remote areas where the chart data is from a survey in 1850 say, and 1/4 mile - or 4 miles - off actual lat/long. If the chart and GPS are accurate, there is no need for radar for fixed hazards.

 

[Adopo]

Are there any pictures and noted damage? Just "morbid curiosity" I suppose, not trying to be rude or anything....and hope it was as minor as minor can be.

 

[MichaelD]

Could have been a lot worse. Grateful for a little luck.

 

[psneeld]

I won't argue whether overlay is appropriate of not... it's just a tool for those that like it or not.

I have been navigating the archaic way for my whole life as just until recently, I haven't been able to afford fancy nav. Even those who I worked for as a pro would not put/keep state of the art nav on the boats/helos I ran/flew.

What I do know is the wisest bit of navigational advice/explanation I ever heard....

The art of navigation is trying to confirm your position that you should already know (at least close). My copilots knew they better never not know exactly where we were if I asked.

If I remember my old school celestial correctly...it required the same...if you didn't know approximately where you were, you weren't going to figure out the calculations. So it even is good advice for old school celestial.

 

[AlaskaProf]

A very good use of radar overlay is to confirm that the GPS coordinate system in use matches the rocks actually seen.

You raise a good point. To site another analogy from ATC: On air traffic radar, terrain echoes are suppressed by a circuit called Moving Target Indicator. But every time a controller starts work, even just relieving someone after a break, you are required to inhibit the MTI and assure that the radar is still aligned with a surveyed echo. Generally just one 4 second sweep is sufficient.



No reason you can't do something similar with your chart plotter.

 

[AlaskaProf]

viewed that channel with unease, and have gone around the outside of Trial Island, even while watching other vessels taking the obvious shortcut. Just me, I guess.

Just remembered why I always avoid that passage:


...because there always seems to be at least one 40-knot Zodiac with two dozen Chinese whale-watchers going the other way!

 

[AlaskaProf]

I’m with alaskaprof. Trying to combine the two makes no sense since they do two different very important jobs.

Yes. Another reason. You seldom need the same range on both devices.

 

[psneeld]

Yes another reason. You seldom need the same range on both devices.

Are you saying with independent radar and plotter that running the same relative scales and range rings isn't all that useful?

 

[AlaskaProf]

Are you saying with independent radar and plotter that running the same relative scales and range rings isn't all that useful?

Yeah, I guess I am. Everyone has their own parameters, but in the 8-knot small boat context, which may not be the same as yours, I have generally found myself using the radar in a 6-mile +or- tactical presentation while the plotter is in a 20-mile-or-more strategic setting; especially since the advent of AIS.


I should qualify this by saying that on the rare occasion of actual IFR, I am very active on the radar range and sensitivity. --which is why I love autopilots.

 

[OldDan1943]

Could have been a lot worse. Grateful for a little luck.

Did you throw the prop away? What about the shaft?

The damage to the bow will buff right out.

 

[darkside]

The only time I like overlays is to confirm a known bouy or marker is what that target on the radar actually is.
Sometimes the look closer or further away than the GPS reality.
The overlay is a quick way to confirm.

 

[OldDan1943]

When I had my N46, I bumped the bottom on the 'spoil' area coming into the port of Miami. It was plainly marked on the chart too. Guess I should have checked and believed the chart. No damage. Had to do with the wave action that day.

 

[SteveK]

Local knowledge developed over time for shortcuts.
I often go through boat pass between Saturna and Samuel island.
But I do not recommend it.
Those that hit the rock approach it in perpendicular when it should be more 45* more along shoreline of Saturna
I have always gone around Trial for that reason as I did not need to know the shortcut.

 

[RedRascal]

I have a confession to make, I go south of Trial and Discovery Islands when I transit between Victoria and Roche harbors. I could weave North of them but it would require me to study the route and spend more time actively navigating between rocks and reefs than I would prefer. I only go that way every few years so I never focused on "learning" the route between the reefs. So I just take the easy way out and stay to the south.

MichaelD I appreciated the post and I realize you were going to have rocks and reefs in your float plan based on your starting location. Glad nothing worse happened like a strut creating a breach in the hull. Thanks for posting.

 

[Hippocampus]

You can control the translucency of any overlay with any of the common brands. Find radar/AIS on a separate screen easier to see but have no reluctance to have radar at a very high translucency on a chart occasionally. When done that way find it doesn’t interfere with reading the chart.
Think more commonly folks get into trouble by not changing scale(magnification) frequently. Stories like this reinforce my opinion coastal is more difficult and dangerous than ocean.

 

[Datenight]

YStories like this reinforce my opinion coastal is more difficult and dangerous than ocean.

+1

Rob

 

[OldDan1943]

I have 2 display. One has RADAR and AIS. The other has charts and used for navigation.

 

[sunchaser]

Trial Island has dozens, if not more on a weekend, of boats per day passing through on the north side - Enterprise Channel. I just looked at a 10,000 scale chart of the area. A safe path, although there, isn't straight forward. Mouat Channel north of Discovery is well marked and straightforward, but beware timing and currents.

Our normal course, as stated by others, is always on the South side of Trial. Seldom is this area a milk pond. Fog and wind can make Juan de Fuca fun enough, Enterprise adds a bit too much fun for us especially with only a 3-4 minute saving.

In SE Alaska there are some challenging courses with plotters taking second place versus kelp patches and standing rocks used as dead reckoning Nav aids. One is the west side of Chichigof Island, open Pacific, be sober and aware. Ditto the west side of Prince of Wales.

 

[Bob M]

A bit off topic, but lately I've been using a Lowrance MFD with an overlay feature called Genesis. The Genesis depth data can come from other Lowrance MFDs, that have uploaded the data to a server. The accuracy of these overlays is way beyond anything you'd see on C-Map or Navionics charts. The MFD also stores bottom data it discovers on a memory card and that data can overlay a chart.


I use the overlays primarily for fishing, but, the uploaded data keeps growing, and I'm guessing that eventually all frequently traveled routes will have this downloadable depth data available.


The display of this data is impressive, because the depth contours can be assigned different colors, which can make shallow areas very easy to distinguish and avoid.



I haven't tried it, but I think Navionics offers a similar bottom depth upload/download overlay feature for Lowrance and other MFDs.

 

[Mike H]

And always remember to carry a few cans of spray foam in the event a leak does occur. Have seen a lobster boat or two laid up for repairs with foam spilling out where they hit bottom.

 

[Moonfish]

MichaelD - I appreciate your humility in an effort to allow the rest of us to learn a lesson!

As for myself, I have duly noted your experience and will try and remember it if I ever find myself considering a similar choice/course.

Thank you!