Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 06-09-2011, 10:43   #1
Registered User

Join Date: Jan 2010
Location: Dana Point CA
Boat: Ericson 27
Posts: 16
Collision Avoidance in Mexico: AIS or Radar or ?

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
__________________

__________________
no_bad_days is offline   Reply With Quote
Old 06-09-2011, 10:58   #2
Registered User
 
svcambria's Avatar

Join Date: Jun 2010
Location: Mexico (currently)
Boat: Panda 40 - S/V Cambria
Posts: 573
Re: collision avoidance in Mexico :AIS or radar or ?

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
__________________

__________________
svcambria is offline   Reply With Quote
Old 06-09-2011, 11:00   #3
Registered User
 
xymotic's Avatar

Join Date: Dec 2007
Posts: 1,076
Re: collision avoidance in Mexico :AIS or radar or ?

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.
__________________
xymotic is offline   Reply With Quote
Old 06-09-2011, 11:53   #4
Eternal Member
 
imagine2frolic's Avatar

Join Date: Feb 2008
Location: Las Brisas Panama AGAIN!
Boat: Simpson, Catamaran, 46ft. IMAGINE
Posts: 4,508
Images: 123
Re: collision avoidance in Mexico :AIS or radar or ?

Quote:
Originally Posted by xymotic View Post
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
__________________
SAILING is not always a slick magazine cover!
BORROWED..No single one of is as smart as all of us!
http://sailingwithcancer.blogspot.com/
imagine2frolic is offline   Reply With Quote
Old 06-09-2011, 12:10   #5
Senior Cruiser

Cruisers Forum Supporter

Join Date: Mar 2007
Location: Santa Cruz
Boat: Boatless Again
Posts: 4,310
Re: collision avoidance in Mexico :AIS or radar or ?

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
__________________
donradcliffe is online now   Reply With Quote
Old 06-09-2011, 12:41   #6
cat herder, extreme blacksheep
 
zeehag's Avatar

Cruisers Forum Supporter

Join Date: Jul 2008
Location: furycame alley , tropics, mexico for now
Boat: 1976 FORMOSA yankee clipper 41
Posts: 17,762
Images: 56
Send a message via Yahoo to zeehag Send a message via Skype™ to zeehag
Re: collision avoidance in Mexico :AIS or radar or ?

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.
zeehag is offline   Reply With Quote
Old 06-09-2011, 13:02   #7
Registered User

Join Date: May 2008
Location: British Columbia, Mexico
Boat: S&S Hughes 38
Posts: 837
Images: 23
Re: collision avoidance in Mexico :AIS or radar or ?

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".
__________________
highseas is offline   Reply With Quote
Old 06-09-2011, 16:02   #8
Registered User
 
svHyLyte's Avatar

Join Date: Mar 2006
Location: Tampa Bay area, USA
Boat: Beneteau First 42
Posts: 3,422
Images: 25
Re: collision avoidance in Mexico :AIS or radar or ?

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...
__________________
"It is not so much for its beauty that the Sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."
svHyLyte is offline   Reply With Quote
Old 06-09-2011, 16:13   #9
Registered User

Join Date: Aug 2008
Posts: 393
Images: 2
Re: collision avoidance in Mexico :AIS or radar or ?

Quote:
Originally Posted by svHyLyte View Post
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.
__________________
h20man is offline   Reply With Quote
Old 06-09-2011, 16:16   #10
Registered User
 
Capt Phil's Avatar

Join Date: Jun 2010
Location: Stateline NV
Boat: Prior boats: Transpac 49; DeFever 54
Posts: 2,749
Re: collision avoidance in Mexico :AIS or radar or ?

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
__________________
Capt Phil is offline   Reply With Quote
Old 06-09-2011, 17:28   #11
Registered User
 
svHyLyte's Avatar

Join Date: Mar 2006
Location: Tampa Bay area, USA
Boat: Beneteau First 42
Posts: 3,422
Images: 25
Re: collision avoidance in Mexico :AIS or radar or ?

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...
__________________
"It is not so much for its beauty that the Sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."
svHyLyte is offline   Reply With Quote
Old 06-09-2011, 17:31   #12
Registered User

Join Date: Aug 2008
Posts: 393
Images: 2
Re: collision avoidance in Mexico :AIS or radar or ?

Quote:
Originally Posted by svHyLyte View Post
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...
__________________
h20man is offline   Reply With Quote
Old 06-09-2011, 17:33   #13
cat herder, extreme blacksheep
 
zeehag's Avatar

Cruisers Forum Supporter

Join Date: Jul 2008
Location: furycame alley , tropics, mexico for now
Boat: 1976 FORMOSA yankee clipper 41
Posts: 17,762
Images: 56
Send a message via Yahoo to zeehag Send a message via Skype™ to zeehag
Re: collision avoidance in Mexico :AIS or radar or ?

clue--they aint using ais nor radar..... the steelies that shrimp dont use either and are too busy watching their trawl.
zeehag is offline   Reply With Quote
Old 06-09-2011, 17:43   #14
Registered User
 
Astrid's Avatar

Join Date: Oct 2008
Location: Northern British Columbia, part of the time in Prince Rupert and part of the time on Moresby Island.
Boat: 50-ft steel Ketch
Posts: 1,885
Send a message via MSN to Astrid Send a message via Yahoo to Astrid
Re: collision avoidance in Mexico :AIS or radar or ?

Your best bet would be to station someone forward as a lookout since radar may or may not pick up small craft.
__________________
'Tis evening on the moorland free,The starlit wave is still: Home is the sailor from the sea, The hunter from the hill.
Astrid is offline   Reply With Quote
Old 06-09-2011, 17:59   #15
Registered User
 
svcambria's Avatar

Join Date: Jun 2010
Location: Mexico (currently)
Boat: Panda 40 - S/V Cambria
Posts: 573
Re: collision avoidance in Mexico :AIS or radar or ?

Quote:
Originally Posted by zeehag View Post
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
__________________

__________________
svcambria is offline   Reply With Quote
Reply

Tags
ais, collision, Mexico, radar

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Problem with AIS taku OpenCPN 4 03-10-2014 10:17
New SiiTech AIS Reporting System For Yachts sinbad7 Marine Electronics 36 05-08-2011 07:51
Route Properties, Missing Functions James Baines OpenCPN 13 13-07-2011 05:31
AIS Reception Issue twistedtree Marine Electronics 72 03-07-2011 04:57



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 10:37.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.