Wreck Finder

[captndale]

I have been considering buying an EchoPilot Wreck Finder. It is a forward looking sonar with discriminating software for picking out shipwrecks. Does anyone have any experience with this product?

 

[ComputerJoe]

With only a 15 degree width your pattern would have to be really tight or looking really deep. I have been wondering about the Hummingbird hull mounted side scan. It dosen't go deep but gives you a great scan width.

I have a Matrix and haven't had the time to play with it yet, and now it's obsolete.

 

[boydski]

The Humminbird Sidescan units work really well in Fresh Water to depths of 150'. You can see 300' to each side of the boat and can locate large wrecks as deep as 200' using a transom mounted transducer.

I have had very good luck at finding wrecks with one ( locating well over 100 wrecks in two years of searching - and published a book about them ). Some days, when working in fresh water in the 100' - 150' range, we'd locate a dozen wrecks in a couple of hours of searching.

They are a great tool for dive boat captains.

Sample Images:

PB4Y Bomber at 165'

Burned out Minesweeper Hull (wood) at 200'

 

[simcoediver]

Very interesting! Is it easy to recognize if what you see on the screen is a wreck? if you did not know if it was there?Is this something that you can learn to read as you go along?
I would consider one for my boat.

 

[DennisS]

The Humminbird Sidescan units work really well in Fresh Water to depths of 150'. You can see 300' to each side of the boat and can locate large wrecks as deep as 200' using a transom mounted transducer.

I have had very good luck at finding wrecks with one ( locating well over 100 wrecks in two years of searching - and published a book about them ). Some days, when working in fresh water in the 100' - 150' range, we'd locate a dozen wrecks in a couple of hours of searching.

They are a great tool for dive boat captains.

Sample Images:

PB4Y Bomber at 165'

Burned out Minesweeper Hull (wood) at 200'

How do you get the water column (the empty area) out of the center of the chart.

I'm impressed with the depth you're getting

 

[boydski]

How do you get the water column (the empty area) out of the center of the chart.

I'm impressed with the depth you're getting

Hi Dennis,

At this point, you really can't get the water column out of the middle of the screen. I know Humminbird is working on tweaking the software to allow it to be removed, but I don't know the status.

However, I have run right over the top of wrecks before (in the blind spot directly below the boat) and you do get a hard (white) return on either side of the boat that I've learned is something right below me. Fortunately, the down-looking sonar is still running and recording, so you can quickly switch screens to the down-looking fish finder and see what you just went over the top of.

is it easy to recognize if what you see on the screen is a wreck? if you did not know if it was there?Is this something that you can learn to read as you go along?

It takes some time with the unit to interpret what you are seeing. We are fortunate that as divers, we can go down and see what it actually looks like on the bottom, so the learning curve is much shorter. I think of the side scan beam like a search light pointing at a 45° angle from vertical. What you are looking for is a "shadow" behind objects. The longer the shadow, the taller the object and the more vertical structure it has.

After running this unit for a couple of years now, I can pretty much tell what kind of wreck we've located and if the pilot house is still intact, etc., just by looking at the side scan image.

In shallower water, you can even spot items like anchor chains, crab pots and toilets on the bottom.

 

[ComputerJoe]

What kind of thermoclines have you worked through? They can give the big sidescans fits up here.

 

[boydski]

What kind of thermoclines have you worked through? They can give the big sidescans fits up here.

Actually, both of the examples above are shot through fairly good thermoclines. The bottom temps here are about 45° and somewhere in the 25' - 45' depth range you'll find a thermocline with water in 55-65° temperatures. However, I think there is enough surface traffic and wind that it keeps the thermocline from being too acoustically "hard".

 

[ComputerJoe]

I think you might be on to it, "diffused Thermoclines." In 5' up here we can go from balmy surface temps (55) to bottom temps of 39. I know they have troubled some with sidescans. Lowering the fish would eliviate the problem but it would also reduce the track width.