Thread Tools Display Modes
Old 09-11-2016, 05:50 AM   #1
Senior Member
Join Date: Dec 2007
Posts: 316

When Electronics Lie | Boating Magazine

tinped is offline   Reply With Quote
Old 09-11-2016, 06:20 AM   #2
High Wire's Avatar
City: Englewood, FL
Country: USA
Vessel Name: Irish Lady
Join Date: Dec 2007
Posts: 996
Good topic.
In very shallow water the sounder sometimes ignores the first bottom echo and shows the second. IE bottom readout is coming up 4.5 ft, 4.0 ft, 3.5 ft, 6.0 ft, 5.5 ft thump hit bottom. This is why I prefer a graph fishfinder over a strickly digital DF. You can easily see this happen.
Another is using too much Sea Clutter adjustment on radar. Targets close to the boat disappear.

High Wire is offline   Reply With Quote
Old 09-11-2016, 07:10 AM   #3
CaptTom's Avatar
City: Southern Maine
Country: USA
Vessel Name: Cygnus
Vessel Model: Prairie 36 Coastal Cruiser
Join Date: Dec 2012
Posts: 1,020
Agree with High Wire on the radar. Sometimes I prefer my old Furuno CRT unit that I almost threw away. It's easier to make manual adjustments to tune in just what I want to see.

I also agree with the article on keeping electronic charts up to date. While it's true that the rocks don't move, channels do. Buoys are moved or removed. Fish farms spring up. New rocks are "discovered." Lighthouse and foghorn characteristics change. Bridges are rebuilt with new clearances. New regulations are enacted. Offshore platforms, wind farms and pipelines are built.

Even with charts less than a year old, I've seen all of these, with the exception of the "new" rocks. That one I just barely missed - by sheer luck. It was published in the LNM the following week.
CaptTom is offline   Reply With Quote
Old 09-11-2016, 08:27 AM   #4
Senior Member
kchace's Avatar
City: Brookline
Country: USA
Vessel Name: Blue Heaven
Vessel Model: Albin 43 classic double cabin, twin 135 Lehmans
Join Date: Sep 2013
Posts: 384
I've experienced all 3 scenarios from the article. I think in many cases experience and paying close attention are needed to remain unscathed. I really really try not to rely on luck but sheer luck has saved me a couple of times.

kchace is offline   Reply With Quote
Old 09-11-2016, 08:45 AM   #5
psneeld's Avatar
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 12,720
I have to be a little nit picky on the article title though...

While good info....electronics generally don't lie...they just spit out whatever limitation is there. There is no intention to ceive on their least not the possessed ones...

We as operators should be aware of all the equipments limitations, beyond electronics....even to include the captain.

Sometimes the captain is misinterpreting perfectly good data.

This can be true with more and more input....loss of situational awareness is something that takes discipline. Some captains can focus better than others and even old timers suffer from over confidence.
psneeld is offline   Reply With Quote
Old 09-11-2016, 09:00 AM   #6
Senior Member
Islanddreamer's Avatar
City: Kingsville, MD
Country: USA
Vessel Name: Slow Ride
Vessel Model: Albin 36 D/C Hull 46 Dec 1978
Join Date: Mar 2016
Posts: 128
Recently had a similar situation with Navionics' depth readings. Was looking for a depression to fish in. Electronic chart was showing 5-12' going toward the hole. I thought the boat was performing sluggishly and noticed the depth sounder flashing. Oops. Got free before the tide went completely out. Severe pucker. Was able to paddle dink around taking manual soundings with an oar to note where the bottom started to get deeper, and with a few maneuvers get her free.

And I updated my chart that morning. The bottom was sandy thank goodness, but lesson well learned. Won't go there again.
Any day aboard is a good day.
Islanddreamer is offline   Reply With Quote
Old 09-11-2016, 10:30 AM   #7
Xsbank's Avatar
City: Duncan Cove, BC
Country: Canada
Vessel Name: Gwaii Haanas
Vessel Model: Vancouver Shipyards Custom Aluminum 52
Join Date: Sep 2013
Posts: 1,629
Navionics has LOTS wrong with it, depending on the location. Harmony Islands is a good example, Navionics got most of the thing wrong. Numerous coves that have been surveyed and appear on Canadian charts show as blank spaces on Navionics. C charts are virtually the same but their errors are all different. I guess Canada is not a big enough market to worry about accuracy, after all you have to agree to a disclaimer to use them.
"...Tongue tied and twisted, just an earthbound misfit..."
Xsbank is offline   Reply With Quote
Old 09-11-2016, 05:34 PM   #8
High Wire's Avatar
City: Englewood, FL
Country: USA
Vessel Name: Irish Lady
Join Date: Dec 2007
Posts: 996
I found on my Standard Horizon GX2200, the heading can be selected True or Magnetic. The T or M letter changes on the display but the value of degrees always stays True!
My Garmin 5212 plotter shows us transiting over land for most of the Okeechobee Waterway.

High Wire is offline   Reply With Quote

Thread Tools
Display Modes

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

All times are GMT -5. The time now is 04:13 AM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012