REEFS, & THE LIKE CRASH AVOIDANCE, DETECTION!!

[Posh]

Dear sailors & the like
I am in search of the latest tech. to avoid my cat of hitting reefs, containers etc, & the like that are out there as hazards & is a must have.
I am talking about if there is anything better by all means let me know, forward sonar.......what is the best available out there?
from a screen perspective, in color, detailed info, alarms, & from what is below all the way to the front, I will appreciate your feedback, questions & so on regarding this investment, but is also a safe way to cruise & be safe, more & more cat & others are hitting reefs & this is not cool.
Please advise.
thanks

[GordMay]

Greetings and welcome aboard the CF, Posh.

Back in ancient times, I always used the Mark 1 eyeball as my collision avoidance device.

[boatman61]

Originally Posted by GordMay

Greetings and welcome aboard the CF, Posh.

Back in ancient times, I always used the Mark 1 eyeball as my collision avoidance device.

Agreed.. Forward looking sonar is still pretty useless..
Good navigation is helpfull with reefs.. they dont move so easier to avoid.

[Reefmagnet]

I once looked at buying a boat that was fitted with the latest forward sonar. It was having $80000 worth of repairs done to it after hitting a reef in Fiji @ 7 knots. I always thought that if perhaps that boat hadn't been fitted with forward sonar it may have avoided hitting the reef at that speed. Relying on technology can be a double edged sword!

[Tetepare]

Originally Posted by GordMay

Greetings and welcome aboard the CF, Posh.

Back in ancient times, I always used the Mark 1 eyeball as my collision avoidance device.

I am such a big fan of this method that I use two. Sometime I borrow more from crew. They do work better in daylight.

Other tools include depth sounder, GPS, and paper charts.

[danielamartindm]

One of the minuses of hi tech instrumentation is that it can divert your attention away from your vessel's immediate surroundings.

[belizesailor]

Originally Posted by boatman61

Agreed.. Forward looking sonar is still pretty useless..
Good navigation is helpfull with reefs.. they dont move so easier to avoid.

Yes, used to have one, was pretty useless at least in my application (shallow water, soft bottom...worst case for forward looking). Maybe tech has improved.

Best tool for avoiding reefs is forward looking eyeballs wearing good quality polarized lenses...not eyeballs glued to a chart plotter screen. In Belize, I have literally watched bare-ly-boaters run aground on clearly visible shoals/reefs because they were fixated on their chart plotter with inaccurate charts!

I keep a pair of Maui Jim's (great clarity/polarizarion) aboard, carefully stowed in a protective case, which are reserved exclusively for eyeball navigation.

Even good charts become useless in more complex areas of Belize, Bahamas, San Blas Panama, etc...they just dont have the necessary level of detail for threading the really complex shoals & reefs in some areas of these places. One exception: Bahaus' charts in the San Blas...extreme detail in some infrequently traveled/charted areas.

Example: Glovers Reef Atoll Belize, look at the interior of it on Google Earth, the inner lagoon is saturated with coral heads, shoals, reefs...a typical chart is useless. I traversed it with friends last year on a Leopard 47. I put 3 guys across the bows with good lenses (triplexed forward looking cross checking eyeballs!) and we picked our way across...found some great snorkel spots in the process...nobody else goes in there, except a few local fishermen, because its just to complex.

[Saleen411]

How about a high quality camera up on the mast?

[Snore]

I delivered a boat with a 2-3 year old forward sonar in November. In theory it is great. But then I played with it while coming down the ICW.

One need not use the sonar to realize that for it to be a useful tool you need to "see" far enough ahead for the obstacle to be 1) recognized by the operator, 2) reacted to by the operator; and 3)BIGGY- the boat turned. For a boat making 6-7 knots, that is a good distance out. I seem to recall this one having a range of +/- 125 feet (30 meters). That is just not enough for a boat at speed.

My experience was that the tool was useful at under 3-4 knots coming into a new marina, etc.. While coming down the ICW there were many false returns. These appear to have been caused by either dense schools of fish or suspended solids (silt).

Chart plotters, with good charts, probably provide better information. And with the proliferation of satellite imagery, spending some quality time with products like GoogleEarth is worthwhile.

At the end of the day, as others have stated, MK1 eyeball, or MK1A (adjusted for myopia) wearing good polarized glasses is really the key.

[Lake-Effect]

Reefs? Charts and navigation
Containers? A sharp lookout and being on speaking terms with your supreme being of choice.

[skipmac]

Originally Posted by Saleen411

How about a high quality camera up on the mast?

Useful only in

- Daytime only and with the sun high and behind you so light enough and no glare
- clear water
- large, bright display easily visible at the helm
- someone to stare constantly at the screen

So maybe helpful entering a harbor or navigating in shallow clear, tropical waters but not much else.

[boatman61]

Could be a good opening for a small drone submarine capable of 10kts to run 500metres ahead of the boat transmitting back to momma boat..

[Shrew]

Originally Posted by boatman61

Agreed.. Forward looking sonar is still pretty useless..

I have to agree. I have forward-looking sonar. It is really only effective up to around 50 feet. At 8 kts, you're moving at 13.5 feet/ second. This gives you roughly 3-4 seconds to react in regards to collision avoidance.

I find it effective when slowly nosing into a questionable channel, inlet or anchorage.

Charts, proper route planning, actively listening and watching is how you avoid reefs.

Radar helps avoid other boats.

Containers are what they are. Like trying to avoid a rattlesnake hiking in the woods. It happens, but it's pretty rare.

[GrowleyMonster]

Reef avoidance has become much easier since the invention of the lookout.


However I am not sure it has actually reduced the total number of reefs struck. Maybe not. Works on my boat, though.

[cyan]

Sometimes sending a monkey up to the first spreader with polarized shades gives the best results, as the viewing angle can be much better. Now if I can just rig a remote helm up there... (what ever happened to the days of crow's nests?)