Radar reflector

dom

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I have two, one on each cap shroud. When heeled, the windward one is near enough vertical.
(Note to self: replace cable-ties this year!)

Good idea, but unlikely to help much if you're talking about those dinky Plastimo tubes.

I think for sailing vessels ISO 8729-2 specifies a 7.5 m2 cross section for X-Band target performance up to 20 degrees heel. In practice, no non-active reflector can achieve this, so what one is looking for is a decent performance as measured by free-space radar cross section (RCS) across all azimuths from 0-360 degrees and all angles of heel up to 20 degrees. A few 'small' nul or minimal return points at specific heel and azimuth combinations don't matter too much in a bobbing boat. The key here is small.

Plastimo tubes are, alas, riddled with azimuth nuls at a zero angle of heel and almost useless from as little as 5 degrees of heel upwards. Consequently, adding a second won't do any harm, but will probably do little good either.
 

bbg

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And totally and utterly useless! The mast will give a better reflection.

Agreed - but there is a Portuguese courtesy flag. I wonder if some port police said, "you need a radar reflector", and ingenuity (after a late night with several beer cans) came up with a solution.
 

LittleSister

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X Band is 3 cm RADAR
S Band is 10 cm RADAR . . .

Thanks for that informative post.

I take from it that that one can't be sure that a single band RTE will be visible at all. That's rather a lot of uncertainty for £450 quid. The £700 for the dual band may make more sense, but out of the question for many.
 

greeny

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I think the original question was posted to enable OP to meet a regulatory requirement and not necessarily be effective. I do the same. A cheap Plastimo or other brand fastened to the backstay with strong tyewraps and pushed up as high as I can with the boathook. Tyewraps changed every year. If I need a reflector in "anger" I hoist a rain catcher version from the spreaders.
 

James_Calvert

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The regs say vessels should "have" a radar reflector or other means for others to detect them on their radars.

The RYA goes on to give advice on this which I guess is how best to achieving detection. Eg have the largest you can mounted as high as possible, following maker's instructions.

It seems to me that the small tubular ones can't meet the rules because they are no good at being detected. If that's not the case, and it's just a matter of "having" a reflector, then surely one kept below in a locker, even if it's not in an optimal position for detection, meets the rules just as well.
 
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Thanks for that informative post.

I take from it that that one can't be sure that a single band RTE will be visible at all. That's rather a lot of uncertainty for £450 quid. The £700 for the dual band may make more sense, but out of the question for many.
X band is still the band in normal daily use by the vast majority of ships, so there isn't very much uncertainty at all, really.
 

dom

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X band is still the band in normal daily use by the vast majority of ships, so there isn't very much uncertainty at all, really.

Stay within the Dover, Calais, Cherbourg, Portsmouth box in reasonably fine summer weather and I’d say the vast majority of ships will indeed be on X. But for say Channel Islands to Falmouth, or perhaps navigating the Irish Sea, North Sea, Scottish isles, then don’t be so sure. Well worth spending £200ish going XS in that case IMHO.
 

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Stay within the Dover, Calais, Cherbourg, Portsmouth box in reasonably fine summer weather and I’d say the vast majority of ships will indeed be on X. But for say Channel Islands to Falmouth, or perhaps navigating the Irish Sea, North Sea, Scottish isles, then don’t be so sure. Well worth spending £200ish going XS in that case IMHO.

On a short potter out the harbour last week I noticed my Active XS picking up both X and S band in the eastern inshore Solent area. It was 1.5 mile vis' max in mist.
 
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I agree, definitely buy a dual band RTE if possible.
Reading this thread, I rather wish I had done myself, the extra £200 would now be forgotten about, 5 yrs later. (Or maybe they weren't available, can't remember.)

One point, if a ship is using S, that doesn't neccessarily mean she isn't using X.
There is no option for S-band only, I think..
 
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dom

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On a short potter out the harbour last week I noticed my Active XS picking up both X and S band in the eastern inshore Solent area. It was 1.5 mile vis' max in mist.

‘Most’ of those Ss in that area will also be swinging Xs, but I agree that XS is 100% the way to go on an active safety device. Else one would need an additional passive reflector with reasonable S capability.
 

LittleSister

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X band is still the band in normal daily use by the vast majority of ships, so there isn't very much uncertainty at all, really.

That's not what Uricanejack, who gives the impression of knowing what he's talking about, has told us. e.g. "Those who have experience with both will often prefere S Band. For colision avoidance".

for say Channel Islands to Falmouth, or perhaps navigating the Irish Sea, North Sea, Scottish isles, then don’t be so sure. Well worth spending £200ish going XS in that case IMHO.

I'd spend £200 for that, but don't think I'll ever be able to stretch to the £700 it actually is.

(Having said that, on the few occasions I've been caught out in fog I would have paid a fortune at the time to be sure I could be seen.)
 
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To LittleSister, just get an Echo Max X-band.
If you are interested in it all, the RYA 1day Radar Course is pretty good. Another thing, they are 100% reliable if mine is a guide, 5 yrs old. They are easy to sell, and hard to find 2nd hand, because folk seem to keep them..
 

LittleSister

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To LittleSister, just get an Echo Max X-band.
If you are interested in it all, the RYA 1day Radar Course is pretty good. Another thing, they are 100% reliable if mine is a guide, 5 yrs old. They are easy to sell, and hard to find 2nd hand, because folk seem to keep them..

How can they be '100% reliable' if one can't rely on all shipping using X band, particularly in the marginal conditions where it becomes most important?
 

lw395

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How can they be '100% reliable' if one can't rely on all shipping using X band, particularly in the marginal conditions where it becomes most important?

Neither can you 100% rely on the ship's watch looking at the radar at the right time, or taking the right action if they see you.
 
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How can they be '100% reliable' if one can't rely on all shipping using X band, particularly in the marginal conditions where it becomes most important?
I meant it has never malfunctioned..
You can't rely on anything exactly 100%, but phrases such as 'the vast majority', 'almost all', would describe the ships using X band.
Yachts, tugs, workboats, fishing boats, fishfarmers, pilot vessels, bunker barges,Border Force, Harbour Patrols, RNLI, to name a few which spring to mind, will be using X, if using radar at all.
 

Norman_E

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I think the original question was posted to enable OP to meet a regulatory requirement and not necessarily be effective. I do the same. A cheap Plastimo or other brand fastened to the backstay with strong tyewraps and pushed up as high as I can with the boathook. Tyewraps changed every year. If I need a reflector in "anger" I hoist a rain catcher version from the spreaders.

It is to meet regulations. I think that my Active X Band reflector is making me visible, and a passive reflector will add nothing of any real value. Where I sail around the SW Turkish coast I have never seen fog, and am always likely to see ships before they see me. The big danger is leisure motorboats going at speed on autopilot with nobody keeping look out and no amount of radar reflectors will do anything about them.
 
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