Collision Avoidance in Mexico: AIS or Radar or ?

[no_bad_days]

Hello, I hope all is well with you all.

As mentioned before, I am planning on making a passage south into the Sea of Cortez and then spending an extended time there.

My boat is simple with limited (but good solar) electrical power and I now have simple basic com/nav gear: VHF radio and a chartplotter, not interconnected in any way. I have full nav lights, and a radar reflector up.

Last week during a passage back from the Channel islands I had a WAY too close encounter at night with a huge freighter. Long story that I will skip, but i was wide awake, looking intently into the dark for a oil platform I knew to be there and trying to avoid, and I saw what I thought was the platform. It turned out to a ship running very fast, outside the shipping lanes (by 20 miles) with very few lights on, and was coming straight at me so he looked like a squarish blockish sort of thing with a few lights on. (Like an oil platform). He was right on me before I could tell he was a ship coming straight at me.

I got out of the way barely, but have decided to investigate and install the best (yes, meaning effective but still as simple, inexpensive as reasonable) ways to avoid these guys before too late. My research points to The obvious choices of radar and/or AIS or both. AIS has benefits only if the ship is transmitting, radar gives less detail but would let me see something whether they are transmitting AIS or not.

My question for this group is if along the outside coast of Baja (for a few months with very few overnight passages) and then in the Sea of Cortez (with very few overnight passages), do you think ships that might be likely to kill me be transmitting AIS, or would some big old gypsum barge or shrimper not be transmitting or looking and just run me down and not even notice? And is there much benefit in transmitting my own AIS so I show up as a boat to them that would try to avoid and not just a little blip of ignorable white noise on their radar?

When I was in the sea of cortex last year for 2 months, we saw very few big ships at all. just a gypsum barge at anchor and a cruise ship off Lorreto. How sophisticated would these hazards likely to be? Is the real risk manageable without any new gear installed or will I really need this stuff down there?

Any suggestions would be greatly appreciated.

cheers Kyle

[svcambria]

Ships you may encounter with AIS on either side of the Baja: cruise ships (lit up like Christmas trees), the gypsum bulk carrier, the Santa Rosalia, La Paz, and Mazatlan ferries, freigters for La Paz, and the bulk oil barge for Santa Rosalia.

Everything else - including all those little pangas, shrimpers, trollers, and everyone else out and about - will not be broadcasting an AIS signal.

Usually you can read the mast lights on ships to see which way they are heading, and as they are operating in an area with many unilluminated small craft they probably (but don't bet the farm) keep a good look-out.

Michael

[xymotic]

and large ship capable of running fast will likely have AIS.


but, it doesn't take that much to kill you in open ocean. You could just as easily get hit by a yacht on autopilot with a sleeping watch.

Radar gives you other benefits as well, I mean there are not many rocks that transmit AIS.


And as far as transmitting, I think that for the extra couple hundred it's worth it if a ship might see you. IMO it's like adding a radar reflector. we 'hope' it works.

Speaking of, that'd be another good investment, a radar reflector.

[imagine2frolic]

Originally Posted by xymotic

and large ship capable of running fast will likely have AIS.


but, it doesn't take that much to kill you in open ocean. You could just as easily get hit by a yacht on autopilot with a sleeping watch.

Radar gives you other benefits as well, I mean there are not many rocks that transmit AIS.


And as far as transmitting, I think that for the extra couple hundred it's worth it if a ship might see you. IMO it's like adding a radar reflector. we 'hope' it works.

Speaking of, that'd be another good investment, a radar reflector.

Maybe you were too focused on the rig? What will you do about the small fishing trawlers, and pangas in Mexico. They are either with no watch due to short of crew, or no lights if not both.

The shipping lane isonly an indication. Not the law where freighters will be. There's nothing like a good set of eyeballs. Everything else is helpful. Never depend on anyone looking out for you. BEST WISHES in getting there safely, and having a wonderful time........i2f

[donradcliffe]

It would be best to have both, and its not an easy choice.

RADAR VS AIS --PRO'S
Picks up everything (most coastal traffic in Mexico will not have AIS)
Useful for entering harbors at night/in fog (Fog is rare in Baja)

RADAR VS AIS --CONS
more expensive
uses 10x the power
much harder to interpret
less accurate
affected by waves and rain

[zeehag]

spend your money on a good set of spectacles and some good charts and a decent gps and depth. i used my radar only 3 timeson way down. we saw what we needed to see using our eyes.
use decent gps or charts or both for where the rocks are.
what you need to see you will not see-- changes in the water/seas preceding big winds and seas. they come up often sans warning and can knock you down if you are not ready.
binocs also.
and a good spot light to see pangas in the dark-- they donot use lights.

[highseas]

It's always good to have another boat "spot" you in their radar ,to see how strong a signal you paint on their radarscreen.

I have those long tubular reflectors on shrouds above spreaders. I've been told it shows up like a steel boat.

AIS is nice because the data is much easier to read,making correct,quick decisions easier. Targets appear much sooner with AIS.

I want to sell my Milltech receiver and upgrade to a B Transponder, to be "seen".

[svHyLyte]

On our annual trips between Tampa Bay and Key West, I have found radar to be much more valuable.

Even though ours is relatively old technology (R20x Raytheon) we can generally spot anything/everything that might be a hazard to us well before it's within visual range--Shrimpers, Fast-Movers, commercial traffic etc. as well as other sailing yachts, adverse weather etc.

Given the choice between the two, I would definately stay with Radar.

FWIW...

[h20man]

Originally Posted by svHyLyte

On our annual trips between Tampa Bay and Key West, I have found radar to be much more valuable. Even though ours is relatively old technology (R20x Raytheon) we can generally spot anything/everything that might be a hazard to us well before it's within visual range--Shrimpers, Fast-Movers, commercial traffic etc. as well as other sailing yachts, adverse weather etc. Given the choice between the two, I would definately stay with Radar.

FWIW...

A good AIS transmitter receiver is NOT expensive.. less then $500.

here is one that I have used, (worked out of the box with OpenCPN)

WEST MARINE AIS 1000 Class B "Send and Receive" AIS Transponder at West Marine

so.... why skimp? and the transmitting allows the big bad ships to know you are there....

it is not an excuse to not keep watch, but.. they do see you....

Also, AIS is nice in that it shows the speeds and headings of all the targets....

so, one can quickly see what the circumstances are, and react accordingly.

[Capt Phil]

Unless things have changed a lot in the Sea of Cortez, I think that 'Zee's' advice is good. Not many ships with AIS or functioning radar to pick you up. Better to keep a good watch when traveling, particularly at night.

Mexican navy ships are probably the most prevalent and they tend to keep a good watch.

Just time your arrival at busier corridors to coincide with daylight... it's a great place to cruise, relax and compare margueritas from various ports of call...

cheers, Capt Phil

[svHyLyte]

Maybe it's just me, but something tells me that no fishing panga zooming between Loreto and Isla Carmen at 0'dark-30 is using AIS. I may or may not see him on radar--although with ours I likely would--but I darn sure won't see him/her on our AIS display.

FWIW...

[h20man]

Originally Posted by svHyLyte

Maybe it's just me, but something tells me that no fishing panga zooming between Loreto and Isla Carmen at 0'dark-30 is using AIS. I may or may not see him on radar--although with ours I likely would--but I darn sure won't see him/her on our AIS display.

FWIW...

I do not think it is just you.. the panga and small stuff probably is not using AIS...

But anything bigger 100Tons should be... and the cost benefits of AIS in my opinion are fair.

but the small stuff will be difficult to see, as not all of them use lighting...

[zeehag]

clue--they aint using ais nor radar..... the steelies that shrimp dont use either and are too busy watching their trawl.

[Astrid]

Your best bet would be to station someone forward as a lookout since radar may or may not pick up small craft.

[svcambria]

Originally Posted by zeehag

clue--they aint using ais nor radar..... the steelies that shrimp dont use either and are too busy watching their trawl.

And many pangas do not even use (have) lights - they will flash a flashlight as you approach (if it still works). Seen them up to 100 miles offshore Columbia and Ecuador...

Michael