is forward facing sonar worth it?

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steve yates

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My mate is reequipping his twister this winter, he's looking to get a 9" chartplotter in it, and was asking me if its worth paying £500 for the transducer for forward facing sonar. He is based on the w & nw coast of scotland though intending to go further afiled in the next few years.

I have no idea, but am curious as to the answer, what do you guys think?
Does anyone use it?
 
I guess most people think not, as it doesn't seem to be commonly used.

I tend to think a 3D sonar like EchoPilot make would be very useful, but too expensive for most yachts. A two-dimensional sonar (which only emits a vertical "fan" directly in front of the boat's centreline) seems like it would be rather difficult to interpret when sounding up a narrow channel etc.

Pete
 
Sandy said:
A few pals who fish seriously have them. For me they are a complete waste of time.
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There speaks someone that has never run aground! I've spent a lot of my sailing life in places where water is often in short supply and always nervous that I'm about to run out of it beneath the keel - the idea of forward facing sonar has always been attractive. I did enquire about it when we were kitting out our previosu boat and the information I got from the various potential suppliers was that fitting it on a sailing boat is problematic because of the underwater profile - often nowhere convenient to mount it. They really are more targetted at mobos with plenty of flat hull underneath and no keel to get in the way.

That said, the B&G mentioned above does seem to have an option that might work.
 
Depends to a degree to where you sail and of course how much you are willing to spend on your boat. I fitted one of the echo pilot two dimensional ones knowing I would be cruising amongst coral reefs. Found it to be very useful and in particular anywhere when creeping in to anchor as you can see how quickly the bottom shelves. I know pvr thinks that they would be difficult to interpret but I didn't find that you can always briefly turn the boats head off course as it were and it will show you the channel sides and with it I have spotted the odd rock in my path and once in the dark, a mooring (well I guess the chain & tackle) I'd failed to spot.
I would find it hard now without a forward looking sonar. The newer ones look even better.
 
It depends where you sail. I've had an Echopilot for a few years now and in a few places it has saved me from a grounding.
One thing that one notices is the comparison with the standard depth sounder. Although the transducers are within a metre from each other, the Echopilot gives much more warning of approaching shallows. The depth sounder seems to be about 3 seconds behind in its recording of the depth under the keel.
The Echopilot is only useful when at slow speeds under motor. It doesn't see far enough ahead to enable evasive action at speed.
 
There is a cheap manual option, without the need for a special power supply or transducer.

Fishing rod, line, weight and a float.

Get a member of the crew to stand near the bow. Set the float for minimum depth required and cast forward. If the float stands upright you can carry on sailing. If the float does not stand up,
have a beer until there is more water.
 
I had an echopilot in an old slow mobo and I found it fairly pointless, it would show you what you are about to hit but not in time to do anything about it, I'm on the east coast where it's all shallow anyway and the less depth the less distance ahead it sees, as soon as the water got murky with sediment it was completely useless and that was usually heading into a shallow river entrance when I wanted it for.
When the transducer packed up I never bothered to fix it.
 
In my opinion yes.

I have sailed in some very shallow and narrow channels in the Bahamas, East Coast USA, French Canals and the Solent.

It's been fitted to our last three sailing boats and I would never go back to a straight down depth finder. We can see up to 100mts ahead and it helps find our way through places we usually wouldn't go through.
 
jonic said:
In my opinion yes.

I have sailed in some very shallow and narrow channels in the Bahamas, East Coast USA, French Canals and the Solent.

It's been fitted to our last three sailing boats and I would never go back to a straight down depth finder. We can see up to 100mts ahead and it helps find our way through places we usually wouldn't go through.
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Which make/system/model would you recommend based on your experience. Thanks.

Www.solocoastalsailing.co.uk
 
Briefly, my opinion or answer would be that it depends what for and what boat.
If it’s to stop running aground, I’d think likely not, unless you are going very slowly. Perhaps like someone posted above, it may be enough that odd time in unfamiliar waters. The smart arse answer to that would of course be to look at charts, haha.

If it’s for fishing and trawling, I hear they are very good. To further comment I’ve looked at the dragonfly models and been impressed by their ability compared to my ageing garmin 450s. I even listened to a Chandler tell a story of a local near Inverness find a long lost anchor after fitting one to his boat. That’s how much detail they show.

Concluding...my answer would be go for it. Who doesn’t love a gadget onboard and why would you not fit the latest or best tech available, within reason. When I fitted the garmin to my own boat, I quickly realised it doesn’t sound well at all when the boat travels at speeds over 30 mph...and certainly not at all, sending the screen haywire, at full throttle and 67mph, haha. Forward facing sonar certainly wouldn’t help much at that speed !
 
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I thought 'forward-facing' meant it could detect solid objects floating in the water ahead, early enough to enable avoidance.
 
LONG_KEELER said:
There is a cheap manual option, without the need for a special power supply or transducer.

Fishing rod, line, weight and a float.

Get a member of the crew to stand near the bow. Set the float for minimum depth required and cast forward. If the float stands upright you can carry on sailing. If the float does not stand up,
have a beer until there is more water.
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We use charts. :)
 
dancrane said:
I thought 'forward-facing' meant it could detect solid objects floating in the water ahead, early enough to enable avoidance.
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I think the makers will tell you it’s for fishing, detecting fish as a target maybe. Likely won’t suggest it for avoiding hazards. Presuming as much, at least. May be wrong.
 
QBhoy said:
If it’s to stop running aground, I’d think likely not, unless you are going very slowly.
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If you're feeling about in the sort of anchorage or channel where a forward-looking sonar would be useful, you will be going very slowly in any case.

QBhoy said:
The smart arse answer to that would of course be to look at charts, haha.
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Again, if you're looking for a gap in a sandbank with 18" under the keel, the charted contours and soundings will be nothing like detailed, precise, or recent enough to be any use. Especially since nobody submits surveys of backwater creeks to the HO and there's little incentive for them to do their own there.

This is the easier and fractionally-longer-range version of Dylan feeling about with his bamboo cane.

I'm glad to hear from those with experience that the "casting from side to side" technique works. It's hard to judge from pictures.

Pete
 
prv said:
If you're feeling about in the sort of anchorage or channel where a forward-looking sonar would be useful, you will be going very slowly in any case.



Again, if you're looking for a gap in a sandbank with 18" under the keel, the charted contours and soundings will be nothing like detailed, precise, or recent enough to be any use. Especially since nobody submits surveys of backwater creeks to the HO and there's little incentive for them to do their own there.

This is the easier and fractionally-longer-range version of Dylan feeling about with his bamboo cane.

I'm glad to hear from those with experience that the "casting from side to side" technique works. It's hard to judge from pictures.

Pete
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Hi Pete.

I’m not sure any of your example situations are too sensible. “Feeling about” sounds risky and “18 inches under the keel” surely not ideal with a fixed displacement and tidal waters ?

I see what you are saying though.
 
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