Simrad Forward Scan - How's it working?

[mvweebles]

Anyone using Simrad Forward Scan? I searched the archives. There was some chatter/interest back in 2016, but no real-life experience. Hoping that changed.

My usage would be when 'feeling' my way through skinny water or into an anchorage, so not at speed.

Peter

 

[rsn48]

Guys come on here and ridicule forward looking sonar, the vast majority of these guys are east coasters where there has been much more charting done. There are places on the West Coast north of Seattle, into the Broughtons in BC where islets have been left off and shoals have not been recorded, this is more true in more isolated areas.

Below I have linked a chart of Haida Gwaii (BC) but I don't know if it will pull up for you the areas I am looking at. Haida Gwaii on the West coast in particular has very poor to no charting. You will see areas that have no depth recorded. When you are mucking about in these areas you want all the help you can get. Unless you were critically stupid, you wouldn't be rushing into these areas at speed, but coming in slowly at something like 4 or 5 knots, eyes glued to your forward looking sonar.

Also in BC we have a lot of crap in the water, most notably logs and trees, trees particularly after a heavy winded storm. I was headed to a place call Refuge Cove in Desolation Sound before my boat had forward sonar and many trees were floating around still with leaves on them. I was uncomfortable with taking my boat in while all these trees were around me. So I changed my destination to Squirrel's Cove on Cortes Island and moored there. My boat now does have forward sonar and given the same circumstances with the trees heading to Refuge Cove, I would have turned it on and carried on at about 4 knots into the area much more confidently.

Haida Gwaii Chart. It just a general chart pops up look for Rennell Sound, Kano Inlet and Cartwright Sound, you will see very little information of the ocean bottom.

i-Boating : Free Marine Navigation Charts & Fishing Maps

PS: My unit is Garmin but the principle is the same.

 

[Happy Frog]

I am using it in the Baltic sea (rocky waters) and happy with it. Use it mainly to help navigating through rocks to remote natural islands. Helps a lot to see the bottom profile ahead when you take the boat to shore. I am extremely happy and turn it on always when it gets shallower, let’s say less that 15 feet. The only problem sometimes is marine vegetation which makes the bottomline to go crazy. In those situations I just look at the datapoints and it works ok.

 

[BandB]

We haven't used Simrad, but have used others and are very much fans of forward scan. I've found those who criticize them are wanting them to be something they are not. You can't run 35 knots and hope they'll pick ups something a mile ahead. However, I think they are extremely helpful in situations where you're very tight on draft and knowing exactly what you're facing helps. We've used for shallow anchorages, to find shoals that had been mentioned by others but were not marked, to safely enter marinas with long winding entrances, to locate a piling under a marina dock that had been rearranged and to see the side of a marina where we were instructed to tie had inadequate depth.

 

[mvweebles]

We haven't used Simrad, but have used others and are very much fans of forward scan. I've found those who criticize them are wanting them to be something they are not. You can't run 35 knots and hope they'll pick ups something a mile ahead. However, I think they are extremely helpful in situations where you're very tight on draft and knowing exactly what you're facing helps. We've used for shallow anchorages, to find shoals that had been mentioned by others but were not marked, to safely enter marinas with long winding entrances, to locate a piling under a marina dock that had been rearranged and to see the side of a marina where we were instructed to tie had inadequate depth.

That's exactly the use case I envision. Braille at slow speed in skinny water.

Thanks to all who responded.

 

[Justin]

I remember reading somewhere (don't remember where) that the forward looking technology uses something like a 5:1 ratio. For every 1 foot of water under your boat you can see 5 feet ahead of the transducer. So in 10 feet of water, you would only see 50 feet ahead of the transducer, 20 feet of water would be 100 feet, etc. It sounds like a really cool technology, but seems like you really need to be traveling slow for it to be useful enough to correct your course in enough time. Just my 2 cents...

 

[IRENE]

Echopilot

The Sailing Aquarius folks on YouTube have an Echpilot. They have been through the South Pacific, and the Captain really speaks highly of his unit. You can search their YouTube channel for his opinion of the Echopilot - you may find it useful.

I am planning to add this technology to IRENE at some point...

Good Luck

 

[BandB]

The Sailing Aquarius folks on YouTube have an Echpilot. They have been through the South Pacific, and the Captain really speaks highly of his unit. You can search their YouTube channel for his opinion of the Echopilot - you may find it useful.

I am planning to add this technology to IRENE at some point...

Good Luck

Echopilot's newest version has a 20 to 1 range to depth ratio so a great improvement. This is with a 200 meter forward range.

Farsounder's Argos 1000 now has a range of 1000 meters, is useful up to 25 knots, and has an 8 to 1 range to depth ratio.

I would consider those the two best options.

Still the Garmin and Simrad and other products can be useful.

 

[Codger2]

Interesting thread! I don't have it on my boat but I have been on boats, fishing, that have it. We were fishing "kelp paddies" and trying not to scare the fish (Yellow Tail) that were hiding under the paddies, We would approach the paddy slowly, only as close as we could cast, and we peaked under the paddy with the forward scan to determine if any fish were there. Nothing! We moved on to the next paddy..........

 

[BandB]

Interesting thread! I don't have it on my boat but I have been on boats, fishing, that have it. We were fishing "kelp paddies" and trying not to scare the fish (Yellow Tail) that were hiding under the paddies, We would approach the paddy slowly, only as close as we could cast, and we peaked under the paddy with the forward scan to determine if any fish were there. Nothing! We moved on to the next paddy..........

Garmin's units are aimed to the fisherman population.

 

[RT Firefly]

Greetings,
Mr. J. NO experience with ANY unit but being able to see as little as 50' ahead would suit me fine. I have no problem with bumping in and out of gear and proceeding dead slow. I can think of two occasions where such a device would have prevented a grounding (both soft).

 

[Ka_sea_ta]

I had a Wesmar 6 160 on a previous boat... This is a searchlight type sonar where the sonodome is on an elevator and deployed at a slower speed, anything higher then trolling speed would produce enough artifacts to make it unusable. But for entering uncharted areas or finding bait it was great. The transducer beam could sweep 360 degrees horizontally and 90 degrees vertically or you could choose a sector to view. I think now I would prefer a spread spectrum (chirp) unit with multiple transducers, signal processing has come a long way since the Wesmar unit

 

[twistedtree]

I had a Wesmar 6 160 on a previous boat... This is a searchlight type sonar where the sonodome is on an elevator and deployed at a slower speed, anything higher then trolling speed would produce enough artifacts to make it unusable. But for entering uncharted areas or finding bait it was great. The transducer beam could sweep 360 degrees horizontally and 90 degrees vertically or you could choose a sector to view. I think now I would prefer a spread spectrum (chirp) unit with multiple transducers, signal processing has come a long way since the Wesmar unit

I'm putting a search light sonar in our new boat, but Furuno rather than Wesmar. I haven't used one before, but know a bunch of people who have them. Success seems to be directly proportional to the effort you put into learning how to operate it, and how to interpret the returns. It's not unlike radar, but harder. At least that's what I'm betting on.

 

[PJHoffnet]

My normal AICW cruising speed is around 9knt which is about 4 yards/12 feet a second. My ability to stop the boat from 9knts to 0 takes about X seconds (I've never tried to time this, so let's just call it X for now). So, basically if I can see something that's 12*X seconds ahead, I'm good.

In 'normal' AICW water (depth 10-12 feet in channel), so if we use the 5:1 ratio ... I have ~55 feet to stop, so that makes my 'response time', X a little more than 4 seconds.

For the 8:1 example, I'd have ~88 feet to stop, or a reaction time of ~7 seconds.

Since main 'concern depth' ... water I try to stay out of ... is 6 feet and shallower, I'd think that even at my 'normal' cruising speed, and the shallow nature of the AICW, a forward looking sonar would be beneficial for places where I have concerns about the channel being affected by shoaling (pretty well documented for the AICW), or even more useful, when I'm really creeping along feeling out an anchorage area.

**NOTE, public math is hard, and I'm hoping I didn't make any calculation errors, if so, I'll blame it on the fact I just got back from a socially distanced happy hour.

 

[rsn48]

And if you are in an area you are concerned about, I doubt you'd be doing 9 knots.

 

[menzies]

My post on the Garmins and the new Panoptix transducer.

I have used it a few times on the ICW - by a notorious stretch in Fernandina and checking the new dredging at Matanzas. I really wanted it for the Bahamas and clearly have not had a chance to do that yet.

https://www.trawlerforum.com/forums/s4/new-boat-toy-47337.html