Necessity and installation of a depth sounder in a steel boat...

[Boracay]

I moved on to working on Boracay's forward cabin yesterday.

The big surprise was to find the depth sounder transducer broken off level with the steel plating.

Gotta be fixed!

So the first question is "Does one really need a depth sounder when cruising?".
i.e. Can one get by with a leadline, charts and a bit of luck?

Next question - "Does the transducer have to be pointing straight down?". The old installation had the thing pointing sidewards at an angle of 30 degrees from the vertical.

I'm assuming that the traditional location ahead of the keel is best.

For those who like gory details I include a couple of pics. Who would have thought that antifouling paint and salt crystals could be waterproofing agents.

[Pblais]

"Does one really need a depth sounder when cruising?".

The difference of a steel boat running aground vs. a different style of boat running aground is - nothing. They both get stuck in the mud as easy as the other. Hitting a pointy rock sinks the steel boat just as fast. All the arguments about is a steel boat stronger and the rest of the argument are not about not needing depth sounders. All boats need them.

Sooner or later you need to come ashore and explore the shallow Waters. Better to know what you are dealing with than curse the darkness. It's probably the cheapest and most reliable gear you'll install. They usually last a long time. More than 20 years is quite common.

Straight down is the better. They don't know they are pointed sideways when you install them that way. You can buy transducers made for that situation and adjust to the different angle of the hull. You might as well get an accurate reading if you are going to the trouble and expense.

Since we cruise in shallow water all the time. There are a lot of things I would prefer instead of a depth sounder not working. I like to know how deep the water is when I go aground.

[MarkJ]

Originally Posted by Boracay

i.e. Can one get by with a leadline, charts and a bit of luck? .

Luxury!
Capt Cook knocked off the whole of New Zealand and all the east Coast of Australia with just a leadline and no chart at all. (Just don't sail close to Cooktown)

You new fangled people call yourself sailors with a boat loaded to the gunwales with electronic junk... Just shove the Missus up the pointy end with some string and a pebble and get her to call out the depths: "340 fathoms..."

Mark

[Dave in Eugene]

Necessity and straight down. (note the period). all the best, dave

[Seeratlas]

What Dave said

And MarkJ? Every time I tried that, just about the time she got around to calling out the right number, we hit bottom and over the bow she went..so I never did get to hear the 'fathoms' part


seer

Seriously, Boracay, you can get them as inexpensive or expensive as you like. The garden variety fish finder will actually get the job done, and in many ways is a superior device as with some practice it will tell you a lot about the bottom without you having to dive down to look, not to mention, whether anything worth eating is moving around down there

but there are times when a good chart and a good depthsounder will save your bacon.

I once got stuck in the fog (not my boat) coming back into the states from Canada in the middle of the night (don't ask) ended up having to cross the San Juan de Fuca and shoot a blind entrance thru Deception Pass, in the dark, in the fog, with no radar. Had a compass, a set of tide tables, a working depthsounder and the right charts. And yes, for those who have sailed those waters, the *pucker factor* was VERY high.

[MarkJ]

Originally Posted by Seeratlas

, we hit bottom and over the bow she went..

ROTFLMAO! I hope she took a scraper and some sandpaper

[GordMay]

Originally Posted by Pblais

... I like to know how deep the water is when I go aground.

I believe the depth is 4' - 9" when you go aground, aboard a Gozzard 36.

[Alan Wheeler]

Now that is funny Gord :-)

[ausieman]

A depth sounder isn't an essential item but they certainly make life a hell of a lot easier and can give you a little peace of mind at times. Ahead of the keel is preferable as sounders don't really like overly disturbed water.
I have managed touch the bottom twice and as Murphy's Law dictates they were both on falling tides, luckily I was able to extricate myself both times with a minimum of fuss before the falling tide necessitated an extended wait. (Perhaps I should make the display visible from the helm, just a thought). ...... Ausie.

[Joli]

The sounder is essential to me! I'll happily give up all the other numbers to keep depth.

Originally Posted by ausieman

A depth sounder isn't an essential item

[Alan Wheeler]

When I was teaching the art of live audio mixing to newbies, I had a rule that I believe also fits this topic. Turn off all your effects and other plug ins and learn to mix correctly first. Then once you can mix really well, add in an effect or other device as an accesory to help you do the job better. Many of the young lads used to get compleatly lost and only made things worse by having all the other (in my view) equipment pluged in.
So if we take that to boating, the essentials of navigation should always be the golden rule. Too many of use still rely on equipment to navigate. I am not saying we all should be able to use a Sextant. What I do mean is that we should all have a chart for the area. We should be using that chart. We should be able to know where and what under water obstacles are. We should be able to calculate tides and knowing how to make them work for us and know what happens when we have no choice but to be somewhere when they work against us. And so on. It states very clearly on our chart plotters that they should not be relied upon as an accurate navigational tool. Yet how many of use use it as such. Yes I am guilty of that as well.
We have had situations in NZ in the past of Commercial vessels running aground because the skipper did not follow the legal navigation and operational laws they come under. We have a similar insident on our South Island West coast right now. A fishing vessel ran aground and was holed due to the skipper having one GPS and having that fail. First off, what was he doing navigating by PGS only? why did he not know his position by chart and why did a commercial vessel of that size have on one GPS anyway.
So what am I really trying to say here. (and I preach to myself as much as anyone) Electronics should only be used as helpful add on tools. A sounder can be used to help varify position by noting changes in contour lines on a chart for example. It can help quickly varify an anchoring depth and how much rode one should deploy. But just one of it's big dangers is that it tells you what you are already over. So if the bottom suddenly rises toward you, chances are you are going to physicaly know so, before the sounder actualy tells you.

[LtBrett]

Whether or not you think a depth sounder is a critical componenet for safe navigation, I think most people will agree that the pucker factor is a little lower with one than without one, especially at night. As for mounting, they should be mounted as close to centerline and as far forward as possible in undisturbed water flow. They are tolerant of some deviation from a plumb mounting, but you may lose bottom while heeling. If your hull has more than 7 degrees of deadrise at the mounting point, you can get a tilted element transducer, available in either 12 or 20 degree tilts. Airmar is the oem supplier for nearly every electronics manufacturer, Airmar Transducers Home Page.

Brett

[Alan Wheeler]

Normally we would mount a block to the hull that follows the angle so as the transducer shoots straight down. Brett is correct, but getting a transducer close to center is far from easy at times. The position varies with hull design also. Palnning hulls really need transom mount units, or they lose contact with the water as the hull comes up on the plane.

[LtBrett]

Wheels,

That's the beauty of the tilted element. It obviates the need for fairing blocks, an obvious benefit for sailboats and smaller planing powerboats. In fact, the very best transducer, planing hull or not, is a through-hull. Of course you have to put it where it will be in the water while on plane. Larger sportfishers who fish in deep water can't use the tilted elements because their power output is limited. But for fishing shallower than 200 ft or certainly for depth readings only the tilted elements are hard to beat. Or you can forego the through-hull entirely and use an in-hull transducer. The degredation in performance as compared with a through hull, especially for depth only, will be negligible.

Brett

[rebel heart]

My vote as well is that it's important, but not nessacary. I'd absolutely but it well above radar, ssb, and chartplotters. Those are nice-to-haves. But a depth gauge takes a lot of guesswork out of things, and can really save your butt. Beyond reducing your incidents of grounding while in transit, you can also have a much better idea of your anchoring depth.

If I had to pick one electronic aid for the boat, that would be the one.