Radar Reflectors

[brianhumber]

Just had a week of sunny laziness over on the French Coast/CI area and returned in Mod Vis 2/4 miles on Friday. Had the radar on and all Ships/Fishing Boats/Power Boats displayed well ( radar is JRC ). However passed a yacht at 1 mile with nil reflection whereas another yacht at 4 miles showed clearly. Knowing only too well the priorities on a bridge re surrounding traffic in fog, I concluded I would not like to be on a yacht in very poor vis with a poor reflection image. Must be a niche market somewhere for someone to offer a yacht reflection radar testing service.

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[snowleopard]

a good idea. i was told by the maker of my carbon mast that it reflected like a ship. didn't know how much to believe him so i finally called up a passing commercial ship who told me he had spotted me 8 miles off so i worry less now.

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[GeorgeP]

Am I paranoid?

We just had a terrific week in the Solent - I couldn't believe the weather! I dropped the family off at Lymington and headed off home to Poole Saturday lunchtime. Wind SW 2-3 as forecasted, visibility 3-5 miles. I motorsailed at first (I was on my own with the wind on the nose). Thought I would go through the Needles passage to get a kick from the tide and perhaps be able to sail the rest of the way. As I neared the red bouy near the Needles lighthouse (Bridge, I think), a bank of fog rolled in and covered the lighthouse. It reminded me of some of those old films, like the Incredible Shrinking Man, where he gets engulfed at the start of the film. Oilies on (it was cold), foghorn in hand, nav lights on, I rolled away the genoa so I could see, and listened. Most large ships go up the eastern Solent, but I have seen the odd one in the Needles Passage. My plan was if I heard anything large I would turn right until I hit 5 metres and stay there.

Then out of the fog came a sailing boat, around 7m long. I guessed that visibility was about 100m (it wasn't that many boat lengths away). As they passed me they hailed. I put the engine in neutral and stopped, and then could just make out the words, "Which way is Hurst Castle?" "42 degrees true, 4 miles," I replied. They carried on sailing. As they disappeared into the mist, I looked at them. I could make out 3 young men, T shirts and no life jackets. Shoals to port, rocks to startboard, races downtide, doing 3 knots in a 2 knot current. In the middle of the narrow point of a large ship channel. "Keep to the right," I yelled at them, figuring that at least they would be able to see the land before they hit it. "OK," they said.

Then I thought some more. No sound signals. I couldn't hear their engine. Sails covering their view. I hadn't seem a radar reflector. Where were their GPS and charts? Had they taken a weather forecast? Did they have a radio?

So I called up Solent Coastguard. "It's a real pea-souper out here. Visibilty 100m, just rolled in past the Needles. Saw a small boat and they asked me the way." "So what are you saying?" "Well, they wanted to know which way was Hurst Castle. I told them 42 degrees true and to keep to the right." "So you are saying you are concerned about their experience and equipment?" "Yes," says I. Then I gave safety traffic for myself and signed off. The fog had been advancing faster than they had. If they had more than a mile to go, I would have called out the lifeboat. I hope they made it back OK.

What would you have done?

Post Script

The fog slowly lifted over the next hour, and I did eventually have an excellent sail home.

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[billmacfarlane]

I came back on Saturday with zero vis for 30 miles. Ships gave a great blip on the radar but a mate of mine who was about half a mile in front was barely discernible showing up as a tiny blip which I wouldn't have known was a yacht. He had a standard Firdell on his mast. He said he could see me as a blip and I use a different type , one that sits on top of the mast under the nav lights. There was an article written a few years back in one of the mags trying different reflectors and the conclusion seemed to be that they were all fairly crap but better than nothing.

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[kindredspirit]

Yep. Just off Bray Head on the west coast on Saturday afternoon. In very poor visibility and F6. Had just missed a very large tree trunk with big branches and then I saw a fishing boat (an Aquastar) going at top speed on a collison course on my starboard forequarter. I stopped making way immediately until I saw his intentions. I didn't turn to starboard as per regs but just stayed where I was for a second or two. It was a good thing I did, as when he eventually saw me, he turned hard to port and went around my stern. If I had followed the rules to the letter, it would certainly have been a collison or very, very close.

I was 30 miles from our destination port but I said "enough is enough" and we'll make for the nearest port which incidentally was the home port of the fishing boat. We tied up next to him and said to the skipper "You didn't see us on your radar, did you?" He said, "No, you weren't on the radar. I only saw you at the last moment." I didn't say anything about him turning to port, as he was obviously doing what he thought was the right thing and anyway he was now letting us raft alongside him.

Although I've no radar myself, I had a reflector high up, but the seas were mountainous, tumbling waves all around, and I'm not surprised he didn't pick up a small fibreglass boat. Is the answer a bigger reflector? Or some other way of making a boat pop up on the radar screen?

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[Sybarite]

I don't have radar but I was wondering if it was in any way related to the height of the scanner. I understand that if some of the smaller ones are mounted too high they fail to pick up objects which are relatively close. I read that the ideal height is about 15-20 feet above sea level. Is this right?

John

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[brianhumber]

Having a bendy boat and flexi mast, I was worried about extra wieght on the mast when I fitted the scanner. It is about 15 feet up just above the lowers. On a calm day with flat sea it will pick up French Pot Markers on the smallest range. On the other hand it will show Barfleur at 16 miles - more than enough range for me.
I normally use on a range between 3/6 miles simply because the fast cats come up on you so damm quick. As it was I still missed a Safmarine container chap out of Bay du Seine coming west at about 20 kts in the boundary of the East bound flow waiting for a break in the flow so he could cross over to the west going flow. I assume he was so far North that afternoon to avoid the missing diver and subsequent search north of Cap de Hague on the more normal Bay du Seine west bound routing.

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[tcm]

This strange. On a flat day you should be able to count seagulls, and not miss a single boat. But if sea is mountainouis, a different matter i supose

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[Gordonmc]

Agreed.

The outcome of a series of articles in PBO some time ago was that some reflectors actually work against the vessel's own radar profile and the two combined can cancel each other out.

Other than going for an "active" system the only sure fire way of getting it right is to try a variety of reflectors and have their signature and the boat's monitored on-screen.


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[Twister_Ken]

"Which?" report needed

As every r/r manufacturer's sales pitch seems to slag-off all their competitors, and as r/rs do seem to be so safety critical (witness recent events), isn't it about time a neutral body did independent real-life testing of them and came up with some reliable consistent figures which would allow us to make sensible purchase decisions.

Stand up, RYA.

Either that or set a (high) British Standard to which they must all conform.

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[DeLam]

Re: "Which?" report needed

Huh! RYA .When the requirement for radar reflectors came in, and knowing all the controversy over their effectiveness I contacted the RYA to see if they recommened any particular type or any advice on choice.
I got a snotty reply from Kathryn Burnett who said they didnt promote any commercial prducts(Ha-Ha).
Annoyed ,I contacted Tim Bartlett who had carried out the PBO tests to see if he had any thoughts.His reply was ,basicly if you want to show people you have money go for a Blipper type, if you want just as good but a lot cheaper use the
octohedral ,if you want to to just meet the requirements get a Mobri.
Not much help from anyone , Wondered if the MCA would define more accurately what`s what.Just Kidding

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[petery]

Lots of emphasis on radar relectors - but the quality of the radar itself is IMHO just as important.

I have a basic Raymarine with an 18" scanner mounted on the mast. I was sailing a mile or so off the French coast last week in thick fog and my 'amateur' radar was picking up the flags on fishing floats (albeit on the slight sea) up to a half a mile away and setting off the guard ring alarm.

It appeared to pick up the individual hulls of the catamaran I was following for part of the trip.

.. and I'm certain that commercial boats have an infinitely more powerful unit than I have.

...but as I believe that we must now all legally use some kind of radar reflector 'if practicable' I will be fitting one asap.

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