Attitude changes (Radar)

[Roger Long]

I think, if you poke around in newsgroup archives, you'll find
a post from me about a year ago pontificating about how I couldn't
justify the cost, weight, and power draw of radar cruising in Maine. I
got along just fine with it even before GPS. I was confident of my
navigation to get in close where I was unlikely to encounter traffic,
etc., etc.


My plans for last spring's science cruise were to take me up into the
Bay of Fundy where radar was clearly required so I installed a Garmin
set up that has worked great except for one time. In August the radome
wouldn't show up on the network. No idea why and the problem never re-
occured. I was far up in Penobscot Bay when this happened and the
first thought that popped into my head was, "How am I going to get
home?" As soon as I realized what I was thinking, I had a good
chuckle. I hope it gives you a chuckle as well.


The radar has become one of my favorite things on the boat. While I
could always get from A to B reasonably safely without it, my route
was dictated by traffic avoidance . I'm now have much more route
flexibility as well as being safer. And, wow, I never realized how
many boats there are out there in the fog Besides, just working
with it is a lot of fun.
I went from Portland to Roque Island singlehanded seeing nothing
except for a couple hours of scale up around Matinicus. Last trip I
did another completely blind solo non-stop from Eastport to the Cows
Yard. First thing I saw was the cliffs at the Head Harbor Island
entrance. Worth every penny to be able to do that stuff.


BTW the Seaview mast mount for the Garmin 18" radomes is too long. My
jib hangs up frequently; especially downwind. I'm going to make an
adapter this winter to move it back. Look for alternatives if you are
planning a mast installation.

 

[SanderO]

In low or no visibility it is essential.

 

[Ross]

There has been some discussion about radar reflectors on the forum and this morning I asked a Phd friend at church about foil strips as a reflector. His field of expertice is antennas. He quickly said that half wave length strips of foil will resonate and provide a very good return on radar. Allow that electro-magnetic waves (radar) travel at 296,000,000 meters per second and that you want half wave length strips of foil. 3 giga hertz emissions will have a ten centimeter wave length so 5 centimeter long strips will be the right length. Lower frequency radar will require longer strips. Filling a plastic jug will make a very effective and low cost radar reflector.

 

[Franklin]

ahhhh....say huh? I thougth the radar antenia put out the wave length and you just want to reflect that wave length so any decent amount of metail that is perpendicular would work....aka....the cross metail plates as a reflector.

 

[Joe]

There has been some discussion about radar reflectors on the forum and this morning I asked a Phd friend at church about foil strips as a reflector. His field of expertice is antennas. He quickly said that half wave length strips of foil will resonate and provide a very good return on radar. Allow that electro-magnetic waves (radar) travel at 296,000,000 meters per second and that you want half wave length strips of foil. 3 giga hertz emissions will have a ten centimeter wave length so 5 centimeter long strips will be the right length. Lower frequency radar will require longer strips. Filling a plastic jug will make a very effective and low cost radar reflector.

I'm sure your PHD friend is a smart guy, because he answered so quickly, but unless you actually test this jug of tin foil in real life his opinion doesn't mean a lot to me. By the way,
How do you know when to change over to longer strips for lower frequency radar? Is there a device for that, or do you just get a collection of jugs with various size strips to string up on your spreaders.

 

[Ross]

Joe , An assortment of strips of many lengths in the same jug will work.

 

[Maine Sail]

Joe , An assortment of strips of many lengths in the same jug will work.

Ross,

There have been a number of guys over the years who have tried the tin-foil in the jug and found it to be ineffective. I came across a post just a few weeks ago on this very subject. I will try and figure out which forum I read it on. The Davis Echomaster is cheap insurance but then again your idea of cheap and mine are apparently totally different.

To flatly suggest, on an international forum, that this "will work", without any testing or concrete conclusive evidence, is ill-advised advice at best IMHO. I am not saying definitively that it would not work, it just may, but to definitively say it will work is risky advise someone just may take and get themselves run over...

 

[Don12364]

Ross - Of Course a Jug of Chaff will work ......

BADLY
Not enough surface area or correct orientation.

Sorry to take issue but a 'proper' reflector is of little real cost.
Anyway wouldn't Davis sell them if they worked??

 

[kloudie1]

GREAT !! Sounds like Main Sail's fall project.. !!
Chaff works when thrown out of a plane because it twirls and "twinkles" so the radar waves can get a chance to bounce off a few properly oriented and widely dispersed reflectors.. I dunno about having it in a jug.. probably better than the jug alone but I suspect not so good as a correctly oriented corner reflector. Practical Sailor ran some comparison tests on reflectors a few years back but sadly, they didn't test the jug..

 

[Ross]

I donno! Has anyone really tried them?

 

[kloudie1]

Hey.. I dunno either!.. That's how come I think Main ought to break out the jugs.. I'll volume-teer to drain one.. Much easier than the prop drag test!..

 

[Gail R]

In low or no visibility it is essential.

Essential? No. Nice to have? You bet.

I sail in the same area as Roger. We have survived without radar for 15 years and will continue to do so. If there was more commercial traffic, I might start thinking otherwise, but frankly, Maine is not exactly heavily traveled. In limited visibility, we've got our Davis up in the raincatcher position, our VHF on 13 and 16, and our horn at the ready. We're not shy about doing securite' calls either (in fact, have had one or two responses -- most notably one of the Monhegan ferries who gave us some nice information on targets in the area).

It really pains me to see people insisting that this whistle and that bell are "essential" or should be "mandatory" when there are other tools available to minimize your risk.

 

[Maine Sail]

Essential? No. Nice to have? You bet.

I sail in the same area as Roger. We have survived without radar for 15 years and will continue to do so. If there was more commercial traffic, I might start thinking otherwise, but frankly, Maine is not exactly heavily traveled. In limited visibility, we've got our Davis up in the raincatcher position, our VHF on 13 and 16, and our horn at the ready. We're not shy about doing securite' calls either (in fact, have had one or two responses -- most notably one of the Monhegan ferries who gave us some nice information on targets in the area).

It really pains me to see people insisting that this whistle and that bell are "essential" or should be "mandatory" when there are other tools available to minimize your risk.

Gail,

10 maybe 12 years ago, pre-plotters, I would have agreed whole heartidly but lately we've been watching "plotter captains" running Sea-Rays, center consoles and other fast craft at speeds in excess of 25+ knots always heading straight for the nuns & cans.

For me these days, especially with the advent of the plotter, I would not be without one in Maine, but that's just me, and I put myself in fog situations more than most because i have a high comfort level with it.

What you are missing & not seeing on the radar screen probably gives you some comfort, but if you had it, & saw what you've been missing, you might re-think like Roger has..

Certainly radar is not "essential" but for me I consider it a no brainer. It has saved us with early warning on more than one occasion. Once from a BIW destroyer East of Half Way Rock traveling at what I figured was about 38-40 knots. Hailed them and they gave me their intentions, certainly glad I saw that coming at me on radar with enough time. Don't really know why they would have been traveling so fast, in 1/8 mile vis, other than perhaps systems testing?

We see this more often than not these days.

These clowns had kids on-board, were not monitoring VHF, no running lights, no radar reflector, no radar and did not respond to the horn signals I was blasting. They were doing in excess of 20 knots at full planing speeds. I slowed my course well in advance and they still passed this close without ANY CLUE we were even out there. Someone will get killed in Maine sooner than later with the bone headed in-fog behavior we've witnessed this summer and previously mostly since the inception of the GPS plotter..

 

[Gail R]

Okay, one more factor to consider -- it seems silly (for us) to add thousands of dollars of equipment on a boat like ours. Kinda like the financial equivalent of putting lipstick on a pig. Now if I had your boat, or Tim's, that might be different.

BTW, our closest and scariest encounter with a clueless powerboater was in Portland Harbor in perfect visibility. We were racing, there was a whole line of sailboats all coming in the ship channel on the same couse. Big ugly Carver cruised across the harbor at half throttle with NO ONE AT THE HELM!!! Horn was out of reach; it was a good thing the captain can whistle. At the last second, a head pops up in the bridge and he makes a big turn to port, splashing his bow wave over our foredeck.

He continued on at speed toward Peaks for a bit (probably headed to the bar at Jones Landing for another round), then stopped when he got to Diamond Island Roads. We assume that was to clean out his shorts.

The horn is handier now. But radar would not have done squat for us.

 

[Maine Sail]

Okay, one more factor to consider -- it seems silly (for us) to add thousands of dollars of equipment on a boat like ours. Kinda like the financial equivalent of putting lipstick on a pig.

C'mon Gail she's no pig! I think she has a rather nice behind (see below=sexy). I do agree with waiting till your next boat though and I understand you two have been loosely tire kicking the idea about..

 

[Stu Jackson]

It's not so much the boat but

it IS the people on board.

It is positively chilling to see Maine Sail's picture of the yahoo doing 20 kts in that lack of visibility.

While we haven't seen it here, yet too much, the "dependency" of the power squads on gameboy BS and video is absolutely scary. Push the button, turn the key, drive it like a car has never been more true.

Of course, there are are always the stories of the motor yacht who put it on AUTO and wound up on the rocks. Too bad they end up hitting other people on the way.

While SF may be "known" for fog, it truly is a misnomer and incorrectly applied. Our fog is usually at 1500 feet and just keeps things cool. Perhaps four or five times a year we get the "down on the deck" stuff that you get normally in Maine. If we did, I'd rethink my priorities and install radar. As it is, I have the "luxury" of choosing not to go out those few days, although twice in the past few years I have been out in that and remember the extreme discomfort that I endured, even with our local VTS - it's the fishermen and the yahoos that are the ones I worry BIG TIME about - I know where the big guys and ferries are from our wonderful traffic control system on VHF.

The ONLY good news is that on both coasts they seem to go from nun to can to buoy, so we too stay away from the "obvious" waypoints in limited visibility.

 

[Gail R]

C'mon Gail she's no pig! I think she has a rather nice behind (see below=sexy). I do agree with waiting till your next boat though and I understand you two have been loosely tire kicking the idea about..

Thanks... perhaps a poor choice of words on my part. Indeed we are kicking keels (certain sisterships to your boat are quite enticing) and we would NOT get the return on investment if we put a radar on, only to sell her right afterwards.

She does have a rather nice behind, but we have GOT to do something about that stern ladder! Her behind would be so much prettier without it!