Radar reflector

Norman_E

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I use an Echomax Active X Band reflector. It does not of course reflect S Band and I don't want to buy another active reflector. I know that the small tubular reflectors are not very good but as I am only doing coastal sailing in daylight I think I might fit one. I don't need a discussion of their effectiveness or otherwise as I just want to comply with the rules about having one.
My idea is to tie and sew it to the topping lift so that it is about 2 metres below the masthead. Is this an OK way to fit one? I don't want to tape it to the shrouds because the one I had before buying the Echomax was fitted that way, and it came apart because the tape slipped.
 

lw395

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I think it will move around a lot, it's a significant mass suspended on a string under relatively small tension.

If you want to secure it to the shrouds such that it does not slip, wind on some self-almalgamatiming tape around the shroud and then secure with a clamp, whipping or cable ties.

Also with your plan, the topping lift is no longer available for any other purpose, which may or may not matter.
 

johnalison

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I think that the tube type is a waste of money and space. You would be better putting up an old-fashioned collapsible type in as near to the rain-catch position as possible. In the past I have done this on a flag halyard or backstay. You may need to tape over the edges to prevent chafe on the sail.
 

prv

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I think that the tube type is a waste of money and space.

Depends whether your goal is to be as visible as possible or just comply with regulations. The OP has already stated that he's firmly in the latter camp and not interested in discussions about how well the tubes work against microwaves vs against clipboards. He has an active transponder which will be better than any passive reflector when turned on in conditions where it's important.

I wouldn't consider hanging it from the topping lift, which should be slack when sailing, leaving the reflector banging around causing damage and annoyance and looking silly.

Pete
 

Norman_E

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Thank you. I was forgetting that the topping lift is slack when sailing. I do have to go up the mast to replace the wind instrument before I go sailing, so I can probably fit one to a shroud then, putting it near the top where I can reach the cap shrouds without swinging out too much, or on the intermediate below the second spreader.
 

bbg

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What "rules" require you to have one?

If one is required, you can tape it to the front of the mast near the spreaders (or anywhere else, for that matter). Or secure the top at the spreaders and tape the bottom to the mast. Or do what I did (class rules required a radar reflector permanently fitted) - secure it underneath one of the spreaders, horizontally. Not on top, in case you are up the mast and accidentally put a foot on the spreader. You'll break the tube.

If you acknowledge that it is only "for show" and not effective, put it wherever it is least bothersome. As low as possible (to reduce weight aloft) and out of the way.
 

AntarcticPilot

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To be effective, passive reflectors need to be as near vertically oriented as possible. That's a major limitation on their effectiveness on a heeling sailing boat! But they should be installed so that they are as near vertically oriented as possible. For the tubular types, that really means fixed to the mast.
 

dom

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I don't want to tape it to the shrouds because the one I had before buying the Echomax was fitted that way, and it came apart because the tape slipped.

I'd readdress this question; for the thousands and thousands of ancient Plastimo tubes attached to the shrouds of equally ancient yachts scattered across the UK and France suggests that a near bullet proof method of attachment must be possible.
 

bbg

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Thank you. I was forgetting that the topping lift is slack when sailing. I do have to go up the mast to replace the wind instrument before I go sailing, so I can probably fit one to a shroud then, putting it near the top where I can reach the cap shrouds without swinging out too much, or on the intermediate below the second spreader.

Why do you want to put it up high? If you acknowledge they are useless, you want to put it as LOW as possible to reduce weight aloft.
 

bbg

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To be effective, passive reflectors need to be as near vertically oriented as possible. That's a major limitation on their effectiveness on a heeling sailing boat! But they should be installed so that they are as near vertically oriented as possible. For the tubular types, that really means fixed to the mast.
Edit - if you look at the Qinetic report, there is no real difference between mounting at 0 degrees (vertical) or 90 degrees (horizontal). Neither is optimal. Best performance comes from about 10 degrees of heel. And it doesn't really matter whether that is from 0 or 90. The only difference is that when mounted vertically it will present the entire length to a radar beam, regardless of where the beam comes from. When mounted horizontally, it will only present a very small cross-section from some directions.
But the Qinetic report only looks at X-band anyway. We really have no idea if these things do anything for S-band.

As I say, if it is just "for show", mount it as low as possible and wherever it is most convenient and out of the way.
 
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VicS

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I use an Echomax Active X Band reflector. It does not of course reflect S Band and I don't want to buy another active reflector. I know that the small tubular reflectors are not very good but as I am only doing coastal sailing in daylight I think I might fit one. I don't need a discussion of their effectiveness or otherwise as I just want to comply with the rules about having one.
My idea is to tie and sew it to the topping lift so that it is about 2 metres below the masthead. Is this an OK way to fit one? I don't want to tape it to the shrouds because the one I had before buying the Echomax was fitted that way, and it came apart because the tape slipped.

I believe they must be mounted vertically and that even the poor reflection they give falls to effectively nothing at a very small angle of heel.. Mounted at the angle of the topping lift from vertical means they are almost totally ineffective. This is why the cap shrouds are the preferred location
 

VicS

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What "rules" require you to have one?

If one is required, you can tape it to the front of the mast near the spreaders (or anywhere else, for that matter). Or secure the top at the spreaders and tape the bottom to the mast. Or do what I did (class rules required a radar reflector permanently fitted) - secure it underneath one of the spreaders, horizontally. Not on top, in case you are up the mast and accidentally put a foot on the spreader. You'll break the tube.

If you acknowledge that it is only "for show" and not effective, put it wherever it is least bothersome. As low as possible (to reduce weight aloft) and out of the way.

Solas V ... The same regulations that requires you to do passage planning and to have access to an illustrated table of life saving signals
 
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Spirit (of Glenans)

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To be effective, passive reflectors need to be as near vertically oriented as possible. That's a major limitation on their effectiveness on a heeling sailing boat! But they should be installed so that they are as near vertically oriented as possible. For the tubular types, that really means fixed to the mast.

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!)
 

MikeCC

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How many people have ever been challenged (except by race scrutineers) by any authority for not having a radar reflector? Bit late by the time MAIB are involved - no points awarded for something that doesn't work.
If you do go for a tube, at least use a 4" one which will do a bit rather than the useless 2" type.
 

bbg

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For what it's worth, under the SOLAS V rules, the only purpose of having a reflector would be to meet the requirement to have something that works for S-band. The OP already has a radar target enhancer (Echomax Active X Band) for X Band. SOLAS V says that an RTE meets the requirements for a radar reflector.

So for the OP, X Band is covered. He only needs to worry about S Band. And I have no idea if radar reflectors work for S Band. The Qinetic report only tested for X band, as I recall.

If anyone has an active RTE for both bands, they don't need a passive reflector in order to comply with SOLAS V.
 

Uricanejack

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

So the difference is wavelegnth.
If you look at a commercial vessel you will often see two diffrent sise scanners the smaller 4 or 5 ft long one is a 3cm scanner the bigger 8 to 10 ft long one is a 10 cm scanner.

Back in the early days 3 cm was primarily British 10 cm was primarily American.

There are advantages and disadvantages to each. With a bit of a bias in favour of X band or 3 cm. A lot of older British ships were fitted with two X bands.

3 cm has a narrower beam with and noticeably better definition particularly bearing definition. Which makes it popular for coastal navigation and pilotage.
10 cm or S band is much less affected by clutter. Sea or Rain. Is lesser definintion often means quite small targets appear larger making it harder to discriminate between large and small targets. However this is often seen as an advantage for colision avoidance. Particularly in poor weather.

Modern vessels often have one of each and with modern RADAR displays an inter switch which allows the operator to choose which scanner is in use and on which display.

Older systems had interswitches as well for back up JIK for failure and could be displayed on other display.
Individuals often have a particular preference depending upon operation.

Those who have experience with both will often prefere S Band. For colision avoidance

Good watch keeping practice would be to use both. However good watch keeping practice is not always followed. Or completely understood.

The MAIB report did not clarify the finding in thier report on the Humber ferry and the classic motor yacht colision. In fog the MAIB report finding was the Ferry had only one RADAR in use.
It did not mention the no of radar displays in use.
Or which RADAR was in use. Which I thought was unfortunate. I would like to have heard why. A ship fitted with two operational RADARs chose to only use one, while operation in dense fog.

It’s not uncommon for a single RADAR scanner to be used with the signal sent to a “Master” display which controls the RADAR and a secondary “ slave” radar display. Which is essential providing the same picture to a second observer.
Some times, a choice may be made to pick the X band on both displays for pilotage waters due to its better definition.
My guess is this might be why the ferry was using only one RADAR. Only one RADAR scanner but displayed on a Master and Slave display. So it appeared to be using two. The bridge crew prioritizeing the X bands better definition.

This practice has a few distinct disadvantages. Particularly not picking up a small poor target.

While on occasions S band may be chosen due to its better ability to deal with poor conditions. Often more further offshore.

Just my opinion it is quite possible to encounter large commercial vessels who are primarily using S Band.
 
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