Forward Looking Sonar... Good to Have for Seeing Obstructions Ahead or Not?

[Terra Nova]

Originally Posted by Roy M

Again, it would appear that those who don't use them seem to condemn them...

Come on! Why would anyone who thought poorly of these go ahead and install one anyway?

The scuttlebutt from professional skippers I know, who've used them, and boats I've worked on, is that it's virtually useless for collision avoidance at speed. Then what is its purpose?

[Roy M]

I guess Raymarine, Garmin, Navico, etc., aren't paying due respect to your informed observations. Pity. All that money wasted.

[Terra Nova]

Nah, they'll find a bunch of noobies to sell all that gear to.

[Roy M]

Or early adopters of new technology....

[svlamorocha]

Originally Posted by Terra Nova

it's virtually useless for collision avoidance at speed.

Spot on. I have sailed many thousands of miles with one of those.

While on passage they are effective...

..at reducing your speed by a healthy fraction of a knot. My estimate comes from comparison of speeds of two new sisterships motoring at same rpm with calibrated tachs with same props.

[Siberian Sea]

I own a commercial fishing boat in Alaska and have a lot of time using sonar systems. My unit requires a large installed through hull sonar tube. The cost for a real sonar starts at around 10,000 dollars. These so call 1,000 dollar sonars are nothing more then modified bottom sounders with a forward face transducer.
Overall they are not good and your money would be better spent on good charts, a powerful Furuno color depth sounder and perhaps a GPS plotter and radar. No peace of gear takes the place of a good captain and his use of charts. When you do look at electronics I suggest Furuno and shy away from the cheaper Garmin and Raymarine brands.
I understand its sometimes stressful poking around the reefs and rocks looking for the deep passage through and there is indeed an attraction to yet one more peace of electronic that might help but honestly don't believe the hype given to these cheap so called "sonars".
Lauren Rogers
Wrangell Alaska

[Terra Nova]

Heckufa 2nd post, Lauren!

[CapnBazza]

I had an Interphase many years ago and, once you have learned how to interpret what you see and you realize its limitations, it was a wonderful piece of equipment. Sailed into Woleai Atoll at 1 am using radar and Interphase - no problems. Used it to check that swinging room was clear when I anchored. Kept me in the middle of channels in uncharted waters. Not much use for containers and logs, lost mine when I hit a log the size of a bus just N of PNG. If you can afford one, buy one.

[FastCruiser]

We've got a probe, had one on the last 3 boats and have one on the 42 .. been using it for better than 10 years now and its saved my ass a number of times..
We count on it when crossing a bar or into an anchorage.. because we're always going slow when approching, it works great..
So much so, that I bought an extra unit as a back-up befor they sold out to Garmin.

The first place it proved itself was going into Moss Landing in Montery Bay.. comming in I was well withing the channel markers but the wife yelled and said I was climbing the rocks. a quick look at the probe and I saw what she was talking about.
Later that night at the Yacht Club I mentioned what had happened to one of the members, he laughed and said, yep, when the tide goes out and the wind is from the north, the channel markers drift over the rocks, its local knowledge..
So we saved our boat with the probe.
Used it today leaving SF and stopped in at HorseShoe Cove... It gives me the depth a good distance ahead of the boat. and because we are moving slow when entering, I have time to hit reverse and back out..
Maybe its because I know what it is and how to use it that I do indeed use it.. Guess that you could say, I give a damn what my keel comes in contact with.

[Curmudgeon]

I had it on my prior boat. Problem was, the screen was at the nav station below. It should have been at the helm.

[Roy M]

well, there you go.... Some folks like them, some don't. Guess you have to make up your own minds. I did, and I'm happy.

[hgd137]

I am in the market for a Interphase Probe electronic control box mainly for the LED screen. If anyone would like to sell one please PM me.

[MYTraveler]

On a previous boat, I had an Interphase, and now have a Furuno Ch250 searchlight sonar (which I purchased primarily for fishing). Even the Furuno is about useless for collision avoidance at my typical cruising speed of 8.5 knots), primarily because there are too many false positives (bait, floating kelp, even a sailboat's wake several minutes after it has passed), but also because it distracts from everything else.

On the other hand, both are useful for picking through a narrow channel or checking a remote anchorage.

[svlamorocha]

Originally Posted by MYTraveler

is about useless for collision avoidance at my typical cruising speed of 8.5 knots),

(snip)
On the other hand, both are useful for picking through a narrow channel or checking a remote anchorage.

I agree 100% on both points. Unfortunately inexperienced buyers are led to buying them them for the former instead of the latter. Then they get distracted by the thing while on passage and up up increasing their risk of hitting something they could see with their eyes (like floating stuff in a moonlit night at sea, when the Interphase screen is enough to kill your night vision).

[jdazey]

Originally Posted by Siberian Sea

<snip>.
I understand its sometimes stressful poking around the reefs and rocks looking for the deep passage through and there is indeed an attraction to yet one more peace of electronic that might help but honestly don't believe the hype given to these cheap so called "sonars".
Lauren Rogers
Wrangell Alaska

From another Alaska commercial fisherman, Lauren has it spot on.

Joe
F/V Diamond Lil