Navigating the Reefs of Andros - SailNet Community
Seamanship & Navigation Forum devoted to seamanship and navigation topics, including paper and electronic charting tools.

 
LinkBack Thread Tools
post #1 of 5 Old 08-08-2014 Thread Starter
Senior Member
 
Join Date: Jul 2011
Location: Hypoluxo, FL
Posts: 138
Thanks: 30
Thanked 3 Times in 3 Posts
Rep Power: 4
 
Navigating the Reefs of Andros

We sailed around the northern part of eastern Andros a few years ago and the reefs there are really dangerous. They pop up out of nowhere!
I was checking out that area on my map for a trip we're planning and it's really amazing the difference in the map versions (see image below)... anybody used Navionics maps in the Andros? Pointers?


Last edited by jerryRiggin; 08-08-2014 at 10:35 AM. Reason: image was too large
jerryRiggin is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 5 Old 08-08-2014
Bristol 45.5 - AiniA
 
Join Date: May 2006
Posts: 3,821
Thanks: 5
Thanked 96 Times in 84 Posts
Rep Power: 10
 
Re: Navigating the Reefs of Andros

Something else to consider is that different e-chart makers have licensed proprietary data. Don't know if it has changed now, but Garmin had licensed the Explorer Charts data for the Bahamas which is superb and Navionics had not. So Garmin is (was?) the way to go in the Bahamas.

In the Eastern Caribbean, Navionics had licensed the Imray/Iolaire data so they had the upper hand there.

It is interesting when the paper chart debate happens that people go on at length about how wonderful and accurate paper charts are. I get a sense that they have not been off the beaten track where you get paper charts like the one on the left. In more remote areas, hydrographers focussed on areas that were of interest to navies and commercial shipping and had little interest in the shallow little bays that are interest to sailors. We anchored in a bay in southern Indonesia that was about a mile across. There was one sounding in the middle that was something like 7m. That seemed pretty good so we went for it while keeping a close eye on the sounder. When we got there it was about 12 m deep. We kept heading towards shore for a quarter mile or so until we got to 5 m or thereabouts. In another place we were anchored a couple of hundred metres on land. When we left in the morning, we were in water too deep for the sounder but still on land according to the chart. Much of the world has not been surveyed.

Back home on Lake Ontario after something over 36,000 nm circumnavigator. Not surprisingly there is a lot of stuff I want to get done on Ainia both cosmetically and functionally. Getting an early start so it will be ready to go for next summer (Lake Superior?).
killarney_sailor is offline  
Quote Quick Reply Share with Facebook
The Following User Says Thank You to killarney_sailor For This Useful Post:
jerryRiggin (08-08-2014)
post #3 of 5 Old 08-08-2014
Senior Member
 
Yorksailor's Avatar
 
Join Date: Oct 2009
Location: Pacific side of Panama
Posts: 531
Thanks: 17
Thanked 25 Times in 22 Posts
Rep Power: 6
 
Re: Navigating the Reefs of Andros

We have used Navionics from Northern Canada to Trinidad and three times around the Caribbean and find them excellent value...We also have Open CPN...similar sized errors but just different depending on the source chart.

Once you leave Miami/Key West they are not reliable for close navigation, we have seen errors of up to 500 yds. The reason is that the Bahamas were last charted using sextants and the charts that Navionics are derived from, which may be 50+ years old, are not accurate. Coral and mangroves grow and hurricanes move sand!

Explorer charts are better but still in the Bahamas it is all visual navigating in good light. We see 1-2 boats per year on reefs because they believed the chart plotter.

Enjoy Phil

Last edited by Yorksailor; 08-08-2014 at 11:29 AM.
Yorksailor is offline  
Quote Quick Reply Share with Facebook
The Following User Says Thank You to Yorksailor For This Useful Post:
jerryRiggin (08-08-2014)
post #4 of 5 Old 08-11-2014
BJV
 
Join Date: Sep 2007
Location: Green Cove Springs, Fl
Posts: 209
Thanks: 1
Thanked 7 Times in 7 Posts
Rep Power: 8
 
Re: Navigating the Reefs of Andros

Past 5 years in Bahamas have relied on Explorer with no faults or errors noticed.
Garmin and C-Map have incorperated Explorer into their echarts, Navionics has not.

In the past two years we have heard reports of cruisers running into trouble with Navionics.
bvander66 is offline  
Quote Quick Reply Share with Facebook
post #5 of 5 Old 08-11-2014
Warm Weather Sailor
 
Vasco's Avatar
 
Join Date: Sep 2006
Location: Toronto
Posts: 1,006
Thanks: 0
Thanked 8 Times in 7 Posts
Rep Power: 9
 
Re: Navigating the Reefs of Andros

Definitely do not rely on Navionics in the Bahamas. I pointed out a whole lot of errors to them but they will not tell me whether they have corrected them. I have two of their chips of the Bahamas. The older 2004 one is better than the 2014 one as they had to remove proprietary data from the newer chips that they had "borrowed" from Explorer. If you foolishly rely on Navionics in the Bahamas it will take you over islands! I am stuck with Navionics because I have a Raymarine plotter but I certainly do not rely on it.

For paper in the Bahamas use only Explorer charts. For electronic Garmin or C-Map who both use Explorer data.

Rick I
Toronto in summer, Bahamas in winter.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Vasco is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
dead reefs chuckg5 Florida - Keys 8 04-03-2013 10:08 PM
Andros in the Bahamas CanDrac Cruising & Liveaboard Forum 31 02-08-2013 12:56 PM
Lost in the reefs sailguy40 Learning to Sail 9 04-20-2010 01:37 PM
Andros Island, Bahamas AlanBrown Cruising & Liveaboard Forum 0 12-10-2008 03:11 PM
Looking for Crew Opportunity ..Andros Bahamas - Florida oasstorage Crew Wanted/Available 0 11-25-2004 04:14 AM

Posting Rules  
You may post new threads
You may 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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome