AIS overlay radar ???

[journey on]

Wow, a lot of opinions on the best instrumentation. And here's my suggestions just to add to the confusion.

As far as instrumentation, presently, I'm using a PC for a MFD, running OpenCpn (free) with the US Gov't charts (free.) NOAA for the ocean and Core of Eng for inland waterways. Canadian charts aren't free, by the way. I bought a Lowrance 3G radar which plugs into the PC via the ethernet port, a USB GPS, and an USB Millitech AIS receiver. I feel that's about as low cost as you can get, especially if you have a PC. When all 3 are working together through OpenCpn, it's a great way to navigate. And a big 15 screen.

Nowl, AIS. Few boats on the Mississippi have AIS on, in my experience. Second, if you want to talk to them about passing, use the VHF and ask. And the captains are very polite with us small guys; just ask them if they want one toot or 2 toots (port to port vs port to starboard, if I'm correct.) Personally, since the Mississippi has a well defined channel, I tried just to stay out of the way on the side where the tow wasn't. They're big and slow.

Regarding AIS data, it's another source of data and it's extremely useful. My example is the container and tanker ships coming down the Santa Barbara channel at 20 knts when we're on the way to Santa Cruz Island. Without AIS, it was always a guess as to when to cross their path. And if you guessed wrong, you're in deep trouble. With AIS, there's a definite answer. If their gyro is 90 deg out, you're gonna know it, cause they're going ashore. Always check what's really going on and then use the best data available. Reality is out there, you gotta look.

Boris

[Will-C]

I think the idea of knowing the vessels name you are trying to call might be an added benefit when wanting to hail someone on the VHF. I guess you could call out southbound tug but then you really might NOT know who is actually responding. Thanks for the tips.
D.D.

[Will-C]

I was looking at some of Vesper marines AIS units. I noticed that the XB 8000 AIS transponder sends signals via Wi-Fi or USB cable to another device’s screen. It sells for 745.99 from Defender
Then there is the Vesper Marine Watchmate 850 transponder with its own screen and it has an internal antenna. It also has an anchor watch function and has the ability to take an external antenna if need be. It sells for 830.00 this would be the ticket if you wanted a standalone unit that would not confuse issues with navigation markers waypoints if you have everything on one unit or computer. Not a lot more money. From what is mentioned below seems like AIS might have some advantages that you would not have with radar. But I could see the reason to have both. See below.
Automatic Identification System ( AIS ) improves the safety level of boating by exchanging information about the status of your ship with other AIS-equipped craft nearby. AIS targets are constantly visible even when they are shrouded in fog, in darkness, behind headlands, river bends or other obstructions.
D.D.

[C-Val]

These are all very good thoughts and I thank you all for considering my navigation setup

With what everyone has said, my long-term goal is a 3g broadband radar to replace my old Apelco and added AIS

It looks like I will be saving for awhile for this since I don't have a MFD unit to display either. It looks like a hds8 display unit will be about $15 hundred from gps store which I think is the minimum size for my 22' plus the cost of the radar itself

In the meantime I will continue reading about the wifi idea since it looks like I could potentially use that idea on my tablet setup

David and Val



Thanks again everyone

[thataway]

I am sitting on the bank at Brown's Bay Marina--just North of Seymour Narrows, watching the boats go by from the "Ripple Rock RV park" --I am amazed at how many yachts in this area have AIS (of course it is still high season, and a high concentration of boats. But I have seen several boats with a length of 8 meters and beam of 2.5 meters with AIS B ---this is based on those received by the Marine traffic sight.

I happen to feel that AIS is going to be a lot more important in the future--maybe even required for recreational boats.

Good idea on the 3 G!

[cmetzenberg]

http://gcaptain.com/ais-reliance-contributed-to-dover-strait-collision-report/
Here is a recent incident high lighting how AIS can contribute to a collision and why, i believe, you should never rely to heavily on AIS.

[thataway]

Here was one incident, where there were a number of errors by the watch stander. Not really the "fault" AIS, but that Radar and Visual sites were not involved. The VTS broadcast was ignored, no second watch stander etc. (Perhaps not even a good command of English!).

Not the "fault" of AIS. As has been noted, AIS is just one more tool. I don't overlay Radar on an AIS screen--I have a a separate AIS screen, and it is one of several (including IR, at night), Radar, Radio broadcasts.

Not a reason to avoid AIS.

[rogerbum]

From the article - "Rickmers Dubai’s OOW was alone on the bridge and he did not see Walcon Wizard. He did not keep a visual lookout or monitor the radar. Instead, he relied solely on AIS information for collision avoidance, which neither Kingston nor Walcon Wizard were transmitting." - That's not an AIS issue that's an idiot at the watch issue. I have AIS and am not at all reliant on it to detect everything. I do however pretty much count on the vessels shown by AIS to be present but no one in their right mind would assume the blank space on the screen is empty.

[cmetzenberg]

let me rephrase; an over reliance on AIS. Heck, i'm using AIS right now. I'm just a big fan of using all available means and knowing the limits and errors that can pop up in those means.

[helm]

you can run an AIS app like Boat Watch on you iPAD that will give you a general idea of whats moving around you in in the fog as a supplement to your radar overlay on a chart plotter, as long as you have a an internet connection via your cell service. It was quite useful the last time we went into Astoria on our way down from Cathlamet. We left in clear weather but hit dense fog from the dredge all the way to the West Basin.
Not the most elegant solution but useful
Best
Eric

[hardee]

[hardee]

Alternatives to AIS overlay are available:

1. The Vesper Watchmate (B series Transponder) comes as a stand alone monitor, about 7"diag view, with a very basic coastal outline picture, allowing the ability to both zoom in or out, and to see the targets in relation to both you and the land masses in the area. The Watchmate has capability to show either heading up or north up display.

2. The Standard Horizon GX 2100 or 2150 has, in AIS display mode, a screen that is also zoomable, and shows the targets in relation to your vessel. The display is in relative to your position and I believe is based on heading up.

As a personal note, I do not run radar with AIS overlay, as I prefer to keep those separate. Radar keeps an eye on what is close, Generally 6 miles or less, and AIS keeps track of the big guys that would even notice the bump if they ran over me.

Harvey
SleepyC

[cmetzenberg]

"Would I use the AIS for "collision avoidance and maneuvering purposes", absolutely. Would I rely on it solely? No way."
I guess i shouldn't have been so firm in original statement because what just wrote is basically the point i'm trying to make. I'm saying that it would not be prudent to attempt a close pass to any traffic off AIS data alone.

If you feel like doing some reading, here is a place you can read about AIS various AIS issues. Again, the big issue; the accuracy of broadcast info.

http://www.nautinst.org/en/forums/ais/ais-issues.cfm

[hardee]

Thanks for that link. Interesting reading for sure. Much of what I found was what I would consider fairly old information ( 2003, 2005, 2010 and much of it undated.)

There is a common thread, AIS is not without fault, however, those faults appear to be operator caused (from the Coast Guard giving a wrong instruction to OOW not ensuring accurate info entered into the Class A systems).

Also, understanding where the AIS info is coming from. In the post "A Pinch of Disbelief" from the Nautical Institute (your link),
http://www.nautinst.org/en/forums/ais/ais-issues.cfm/pinchofdis
the AIS info source is web based, not real time AIS unit, and there is no knowing what the delay is, so the discrepancies are explainable, as in positioning or ship movement, not in AIS output errors.

A significant benefit is noted:

[cmetzenberg]

i'll say this tough; if you gave me the choice between a Flir infared system or an AIS system, I'd go infared without a second thought.