Foggy

SeaHorse II wrote:
That's quite a trick...to see a ship (Ferry) coming out from behind an Island.*

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*If there's an island between us and the ferry, the ferry is not an issue * And should the ferry come out from behind*the island, we'll see it, either visually or on radar.* And since we know where all*the ferry paths are in the area we boat in, we don't run in them. good visibility or bad.* We stay off to one side.** Seems dirt simple to me.*

Things just don't happen that fast on the water contrary to what a lot of people seem to think.* They do if you're going 30*knots but we're going eight.* With radar or our eyes, between the time you first see a ship--- assuming you're looking which we always are--- and the time there's even a potential for a problem there's time to play a round of bridge

This whole thing*strikes me as being like people in an airplane when they see another airplane passing them on the airway but below or above them, or there is another plane on a parallel approach to the airport.* From what I hear people say, half the passengers panic that a mid-air is iminent.* I see and hear the same thing with boating--- if there is another vessel, particularly a large one, anywhere in sight people assume a collision is about to happen and it's amazing how many of them get all uptight if not begin to panic.

For people all caught up in their electronic gizmos and who boat with their heads burried in their screens I agree that AIS is proably a good idea since their awareness of what's going on around them is confined pretty much to what's on a display.* But for people who combine their electronics with basic looking out the window, knowledge of the waters and traffic lanes and patterns in their area, and the ability to see something--- on a screen or out the window-- and judge its speed and convergence relative to their own boat with reasonable accuracy, AIS doesn't seem to have much to offer.

Plus I have my own form of AIS in my wife, who's ability to see a distant ship or boat and judge its speed and projected path relative to our boat is uncanny.* I can only assume it's due to her Navy training and experience, an inherent, inherited*ability, or both.* On a couple of occasions I have used the radar to track a ship's convergence*with our path while she did it purely visually, calling out distances and estimating how our paths would cross.* I'm not going to say she duplicated the radar exactly because she didn't, but she was close enough that had we relied on her alone to avoid a potential confrontation with the ship, we would have succeeded.

So somone's going to have to make a lot stronger case than "we can see boats before they appear" before we'll consider AIS a worthwhile investment.

SeaHorse II wrote:
That's quite a trick...to see a ship (Ferry) coming out from*behind an Island!

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*Or what's on the other side of the bridge.

This ferry could "shoot out" anytime from the island.




-- Edited by markpierce on Wednesday 7th of September 2011 06:11:09 PM

markpierce wrote:
This ferry could "shoot out" anytime from the island.

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*Washington State and BC ferries are not going to "shoot out" from behind anything.* They're fast-ish, but not that fast.

As to the foot ferry in your photo, unless AIS has the ability to read a skipper's mind and so know in advance when he intends to cast off and leave, it's not going to give you any "shooting out" info, either

Marin wrote:
Washington State and BC ferries are not going to "shoot out" from behind

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*On the Bay at 17:25 PDT, the various ferries were moving at 26.1, 7.3, 32.4, 35.1, 30.5, 0.0, 14.4, 22.8, 30.6, and 2.4 knots.* Some of those qualify for "shoot out" speed.


-- Edited by markpierce on Wednesday 7th of September 2011 06:34:05 PM

markpierce wrote:
*On the Bay at 17:25 PDT, the various ferries were moving at 26.1, 7.3, 32.4, 35.1, 30.5, 0.0, 14.4, 22.8, 30.6, and 2.4 knots.* Some of those qualify for "shoot out" speed.

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*That's interesting to some people I guess but up here in Washington I'm not all that concerned about how fast the ferries on SFO bay go.* That's a bit like telling me that since the traffic on the M25 around London is at a total standstill (again) tonight*I should plan to take an alternate route home*from Boeing Field in Seattle to Sammamish east of Seattle

No real relevance to whether or not AIS would do us any good on our boat in our waters.

Marin wrote:markpierce wrote:
*On the Bay at 17:25 PDT, the various ferries were moving at 26.1, 7.3, 32.4, 35.1, 30.5, 0.0, 14.4, 22.8, 30.6, and 2.4 knots.* Some of those qualify for "shoot out" speed.

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*That's interesting to some people I guess but up here in Washington I'm not all that concerned about how fast the ferries on SFO bay go.* That's a bit like telling me that since the traffic on the M25 around London is at a total standstill (again) tonight*I should plan to take an alternate route home*from Boeing Field in Seattle to Sammamish east of Seattle

No real relevance to whether or not AIS would do us any good on our boat in our waters.

*That was exactly my point, but from the opposite end.* By the way, I'm sans AIS on the boat.

Before I had AIS I didn't see the need for it. Now that I have it, I wish I had had it sooner. We cruise from WA to BC and AK and it has vastly reduced the stress levels of meeting and crossing with large ships, tug and tows, cruise ships, and fast large yachts.

If you are getting a second VHF, Standard Horizon has the Matrix with a built in AIS receiver. It uses the same antenna as the VHF portion.

The AIS signal can be sent to a plotter or computer nav program.

I've actually "researched" this to a degree by talking to a number of boaters I know who have installed AIS on their boats. Every one of them, so far, has said that while it's nice technology and neat to play with they have all concluded that it's in the "nice but not necessary" category of electronics. They don't regret buying it (it's cheap) but none of them say they have found any real value in it. This opinion has actually been seconded by a couple of marine electronics dealers I've talked to about it. We'd love to sell you one, they say, but we don't think you'll find it much use. So aside from the handful of people on this forum who say they like it, it seems so far to be a "cool toy" with regards to recreational boating. I can certainly see the value in the shipping industry, but for boats like ours it seems like putting a transponder on an ultralight.

At this moment, there are about a dozen pleasure craft in San Francisco Bay with their AIS units broadcasting.* About half are docked or moored.* Just imagine the clutter of signals if a significant portion of the area's thousands of*pleasure boaters were using AIS.

A display like this would be nice.



*(Leaving Lisboa [Lisbon], Portugal.)


-- Edited by markpierce on Thursday 8th of September 2011 02:33:38 PM

I like the fact that my son's tug has an AIS transponder and that I can follow his pecker tracks from the comfort of my easy chair on marinetraffic.com when he is on the job and know where he is in real time. Neat! Other than that, I see no benefit in having it in the area where I boat. If I were in an area where there was a lot of commercial traffic, if might be of use to show where the big boys who have the ability to cause you serious hurt are. But if all boats big and small had them, it sure might get confusing. Electronic information overload. Radar is good.

*As I said before, the only reason I'd go with AIS is due the the under funded toy budget.* The problem with AIS is that it doesn't give you full situational awareness (non AIS-transmitting boats).* Radar shows everything, and even serves as a backup navigational tool, just like the depth sounder. Having said that, while a poor substitute for radar, a $200 USB-AIS seems like cheap insurance against a radar failure.


-- Edited by bobc on Thursday 8th of September 2011 07:33:06 PM

In my early flying days, I remember when "wing levelers" came out. Boy was that neat! And then they added "altitude holds" to supplement the wing levelers. Even better! Did I need those to fly the plane? No, my artificial horizon and altimeter were just fine but I must admit with the advent of auto pilots to go along with the other two, I was in heaven.

And how about when they added transponders to general aviation aircraft? Although you could not see the other aircraft, the controller could see them and YOU!

Remember the first aircraft radars? I certainly didn't need one but we added a brand new Bendix* (color) to the companies Cheyenne ll. While picking my way out of Davenport, Iowa one night, on my way to Scottsdale, AZ, it sure came in handy for keeping me out of and between thunder storms.

How about the invention of the automatic transmission? Who needed those? Hell, with a little release of the clutch & some light throttle, it was a piece of cake to hold the car still while stopped on a grade. (Not to mention the hydraulic brakes.)

AIS? Yes, it's relatively new and will continue to evolve. Do we absolutely need it? I suppose not but I guarantee you that it's here to stay and will get even better.

The title of this thread is "FOGGY", not CAVU! AIS is a big advantage when operating in FOG! A good radar on board and operated by a competent crew person is a "given" nowadays. Guess what? (I can still remember when it wasn't!)

*


-- Edited by SeaHorse II on Monday 12th of September 2011 09:31:52 PM

I've ordered a cheap USB-AIS receiver to use with OpenCPN mapping software. I'll let everyone know how it works out.

I've discovered another option that may work for some of you. If you have a smart phone, it seems there are AIS apps, plus the free website http://www.marinetraffic.com/ais/. I knew about the website, but hadn't thought about people using it while on the water.

I don't have a smart phone with a data plan, so that option doesn't work for me, but I would think it might work for others who have good cell coverage in inland waters.

The AIS receiver arrived this afternoon and I had it working in less than 10 minutes.* I used a Radio Shack telescoping whip antenna, as this unit (Digital Yacht AIS 100) has a BNC connector.

I'm impressed.

Here's a plot with the unit on my kitchen table.** You can see the Mukilteo ferries, and the information that I received from a tug headed for Everett.* The update rate on the boats seems to be about every 10-12 seconds.

I plan on giving it a real workout this weekend - rain or shine.

I think of the AIS as a combination of aviation's transponder and TCAS. It can provide a digital transmission like a transponder to make other appropriately equipped users aware of my position. As a helm display, it can provide me with enhanced situational awareness of those vessels appropriately equipped. It's no substitute for outside vigilance or radar monitoring, but it can provide me with info on some targets which is not available from other sources. AIS can also provide data re: vessel type, call sign and destination to other AIS-equipped vessels that a transponder cannot provide to TCAS aircraft.

"I can certainly see the value in the shipping industry, but for boats like ours it seems like putting a transponder on an ultralight."

Is it a panacea for all situational awareness needs? No. Can it help provide more information regarding the vessel traffic in your area? Yes. Is it worth the cost? Only the vessel captain can answer that. But to categorically state that it is overkill or not worthwhile for all boats like ours seems a bit closed-minded.

Having a transponder on light aircraft greatly enhances the ability of air traffic controllers and other pilots in TCAS-equipped aircraft to observe and take evasive action to avoid collision. Having a transmitting AIS on a boat, regardless of size, does the same thing, whether you notice it's happening or not. How many close calls have I missed because ATC or other pilots saw my transponder signals with enough time to take evasive action? I have no way of knowing, but I suspect quite a few. Would I like to see transponders on gliders and ultralight aurcraft? You bet I would since they often operate in the same airspace as the rest of us. I am not, however, in favor of MANDANTORY installations by FAA regulations.

AIS can be a great tool...another arrow in your quiver, but I hope that AIS never becomes a mandantory requirement for access to our nation's waterways. That, IMO, WOULD be overkill.

FlyWright wrote:

AIS can be a great tool...another arrow in your quiver, but I hope that AIS never becomes a mandantory requirement for access to our nation's waterways. That, IMO, WOULD be overkill.

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*When/if Big Brother requires automobiles to carry tracking devices, mandatory AIS won't be far behind.* Presently have a FasTrack device in my SUV for the convenience of paying tolls, but I'm still able to legally remove it.

There is also a privacy issue with AIS.* Its information is publicly available.* We could track each other's boat movements.

"Its information is publicly available.* We could track each other's boat movements. "

Yes, I know some fishing guides who refuse to use them since they'd give away their honey holes.

BTW, I am also without the AIS as some of my electronics are, like my boat, bordering on antique.


-- Edited by FlyWright on Friday 16th of September 2011 06:39:02 PM

I've just returned from a overnight trip to Port Townsend. In spite of the weather reports, it turned out to be a great weekend. Things were a little lumpy Saturday morning between Deception Pass and Port Townsend, with 20k winds from the South. Things calmed down for a nice afternoon in town. It was wet and windy during the night, and the forecast for today suggested that it would be a rough ride home. It couldn't have been further from the truth. The trip from PT back through DP was perfectly calm -- a mill pond. It was great for spotting wildlife, including what we think was a mink whale that surfaced a few hundred yards from the boat.

Visibility was good both days, perfect for testing the new AIS receiver. The setup was a $200 USB receiver, with a Radio Shack collapsible antenna (not tuned for AIS) located on a shelf near the lower helm. I was using with Open CPN software. Though the setup was far from optimal for range, I was able to see boats out at least 5 miles. I suspect a tuned antenna on the flybridge would give me 20+ mile range.

All in all, I'm pleased with AIS. I find it interesting that you're able to see the boat's destination. It's kind of fun knowing that a cargo ship passing by is headed to Canada, or to Oakland. I also now know that the Victoria Clipper travels at 27 knots.

As this is a receive-only setup. I'm not too worried about being tracked .


-- Edited by bobc on Sunday 18th of September 2011 10:09:14 PM