Radar Reflectors

So for possible legal purposes, I do have a radar reflector. It's a clever dual-purpose device: I also hang the sails from it.

I did used to have one of those pathetic little plastic tube reflectors, but it fell off.
 
Tugw said:
Cyclops or Tri Lens?, I cant make my mind up.Already got an active type but i wanted something in reserve should the lekky decide to die.Ive read loads of reports and i am now completely at a loss

whats the panels opinion?:confused:
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If it's just as a back up I'd go for an Echomax 230 I. What does the I stand for?

Inflatable :)

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You have an active one so keep this one safely in a locker where it won't foul sails, lines etc and put it up if you need to. It's nice and big when it's inflated and gives a good return. When it's not inflated it's about the size of a book.
 
When my boat was new in 2003 we had it fitted with a seeme just to be on the safe side I bought a cheap flat pack octahedral reflector to hoist if the seeme went down, its been in the locker ever since. . . . . .

the report on passive reflectors seems to indicate (to me) that the octahedral is pound for pound the best passive kit out there and its performance is not far behind the most expensive, i.e. not very good at best a waste of time at worst.
 
Octohedrals have been widely used for years. You see them on nav buoys, posts, etc etc.

They work well enough in practice.
They are sketchy at meeting the 10m2 figure, but 10m2 is a pretty big radar signature.
To put it in perspective, 1m2 is a more common target threshold in long range radars.
 
I used to have a Tri-Lens... until it fell off its mount and exploded on the foredeck earlier this season. The @rseh0les at Viking claimed that I hadn't mounted it properly (except that its commonly known that all the old-style mountings were faulty) and wouldn't replace it.

So I bought a small plastic tube in Weymouth, which broke apart and fell off the signal halyard in the West Country.

So now I have nothing.

Never mind, I'm quite safe sitting on the sofa! :D
 
Tugw said:
Cyclops or Tri Lens?, I cant make my mind up.Already got an active type but i wanted something in reserve should the lekky decide to die.Ive read loads of reports and i am now completely at a loss

whats the panels opinion?:confused:
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Save your money - passive reflectors are useless.
 
VicS said:
So long as you are sure it has a RCS of 10m² ?
Quite a substantial sail support device if it does!
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I wouldn't know a RCS if it poked me in the eye. But whatever it is, 10m² seems awfully big for an bit of kit which has a simple projected area of about 0.1 to 0.5m².

I do know that my boat is visible on radar at quite a distance, because I've asked someone if they could see me. Not very scientific, but it gave me a warm feeling.
 
I have a Cyclops 1. The smallest of the three. The thing about passive devices is that they require no volts to work. AIS and Transponders are obviously better as long as you have the power to drive them. As it is, my service battery won't keep my nav station operational for a complete channel crossing without running the engine for a quick re-charge. I'm unsure whether the Tri-lens would take mounting on the masthead with the tri-white on top like my Cyclops. BTW when my original Cyclops suffered a structural failure it was replaced FoC no questions asked, well out of warrenty.
 
trapezeartist said:
I wouldn't know a RCS if it poked me in the eye. But whatever it is, 10m² seems awfully big for an bit of kit which has a simple projected area of about 0.1 to 0.5m².

I do know that my boat is visible on radar at quite a distance, because I've asked someone if they could see me. Not very scientific, but it gave me a warm feeling.
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The 90 degree corners are effective at reflecting the radar waves back where they came
from.
An RCS of 10sqm reflects radar back in the direction it came from as effectively as something which intercepts the radiation hitting an area of 10 square metres and scatters it equally in all directions.

The trouble with observing that your boat is visible on radar is that the mast will be quite effective when it's vertical, but when the boat heels most of the reflected power will go up or down rather than back towards the transmitter.

Passive reflectors are not useless.
They are not as effective as we would like, but they will increase your chances of being seen on radar.
Yes it would be nice to be seen from further away, but presenting a 'solid' target just in time for a ship to miss you is much better than nothing!

I think to give the impression that it's not worth bothering unless you go for an active device is at best misguided.
 
What would really help the situation overall is an active enhancer that doesn't cost £700. I don't know what goes on inside the box but I can't imagine it really needs to cost that much. Obviously Sea-Me et al have a business to run and I'm not suggesting they should drop the price as an act of charity, but if a new competitor could manage a small margin on, say, £200, they'd probably sell loads and a lot of yachts would be a lot more visible.

Pete
 
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We have a collapsible octahedral stowed under the nav table seat (where it remains) to meet any official requirements and an Echomax for everyday use. I wondered how effective the Echomax was so asked one of the Condor ferries if we could be seen... they had us bright as a button on their radar half an hour before they had us visual. OK it wasn't one of the Condor cats so 30 mins isn't that far and I know their radar is pretty high up..... but I found it reassuring.

If you decide to use the Echomax make sure you mount it a LONG way from your own radar scanner.... despite what it says in the instructions I found it was triggered by my own radar.
 
I'm confused now. I have an Echomax 230 and had been feeling secure knowing (thinking) that big ships would see me. Now I'm not so sure although several people have checked with passing ships and been assured that they can be seen. Are the gloom merchants saying that their radar echo would be as large without the reflector?
BTW I don't like to rely on an active device because it can fail like any other electrical stuff.
 
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ghostly moron, as far as I can tell on my little radar boats with no reflector show up just as well as boats without, as the report says passive reflectors are not much use - we sprinkle salt outside the back door to keep the elephants away, we know it works, haven't seen an elephant in the back garden for years. Passive reflectors offer a similar sense of security; ie its all in the mind. :-)


BUT let's be clear about one thing yachts with no reflector are not invisible to radar.
 
Marsupial said:
.....

BUT let's be clear about one thing yachts with no reflector are not invisible to radar.
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There is big dependence on sea state.
The hull of your yacht will disappear into the waves in rough weather.

To be honest, the reports don't impress me much, in comparison with the volume of work I have seen relating to aircraft, missiles etc.
I think some of the engineers who have used corner reflectors for range calibration since the 50's would be quite surprised to be told they don't work.

You still have to believe that the ship's watch is looking at the radar though.
 
It is very easy to use a corner reflector to calibrate a stationary Radar as both are stable, fixed to the ground and the corner can be orientated to give the maximum return. On a boat, the corner isn't in a fixed relation to the radar. It's dancing around in three dimensions, with nine degrees of freedom. If you read the QintetiQ report, you'd see the polar diagrams of the reflectors tested and see for yourself the limitations of simple corner reflectors.
 
trapezeartist said:
So for possible legal purposes, I do have a radar reflector. It's a clever dual-purpose device: I also hang the sails from it.

I did used to have one of those pathetic little plastic tube reflectors, but it fell off.
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A mast is a very poor radar reflector. It's curved, so the reflection back towards the emitter is limited.
 
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