Best radar Reflector for the Money?

[FullCircle]

Confused again.
All you people out there with Radar reflectors, who can say for sure that they are doing what they are supposed, how is that measured, and why are they so expensive?
I want one, but i am buggered if I am going to pay silly marine thought up numbers without good reason.
Your thoughts would be much appreciated.

Thanks

Jim

 

[sailorman]

Hi Jim
wally boat owner done a survey a few years ago & from memory found none any good.
for whats its worth i have a Firdell & hoist to spreaders as conditions dictate.
where in muddy essex r u based
roger

 

[aluijten]

Well Jim, ther are two of us now, I've heard the Echomax should be good, but for the price it should be, I't's almost cheaper to hire a helicopter to help you being seen by others /forums/images/graemlins/frown.gif.

Arno

 

[Neil_M]

I relied on the comparative tests & bought an Echomax EM230, which is reckoned to be the most effective. Difficult to say how well it works when its up there, but when calling ports for entrance such as Ramsgate they have spotted me some way off on their radar so it works for me. Wouldn't venture offshore, or even across Harwich Harbour in poor visibility without a decent one.

 

[FullCircle]

I had an aluminium square one flying off the North Foreland - distance 2 to 3 miles. I was reported late and missing due to sod all wind and no motor. They couldn't spot me. Thats what I am asking for.
Resident of the Ditch known as the Crouch, at Rice & Cole (lovely folk).

 

[FullCircle]

Ahh, Waldringfield, Second Chance was languishing there when I bought her, known then as Blu Fin 2 in the yard behind the pub.
Like it there.

Thanks for input. Have crossed Harwich harbour in blissful ignorance for years. Just getting to grips with a radar whizzy thing, and reflecotrs that may or may not work.

Jim

 

[Neil_M]

yep - just spend all day down in the yard there getting ready for next season...

 

[starboard]

Back in my RNLI days I remember a trial was done on various....no conclusive evidence was obtained that said any one device was an improvement......the theory was a hand full of scrunched up baking foil in a nescafe jar was as good as the one the Yachties wanted to pay £200 for ...as they say you pay your money and make your choice but to be honest when it comes to boating we all seem to be suckered in by the glossy adverts.

Good echo's

Paul.

 

[Birdseye]

A radar reflector can only reflect back what lands on it - imagine therefore how much reflection you would get looking across the same distance at a mirror of the same size as your reflector.. So the first thing that helps a radar reflector is size. The bigger, the better.

Then it has to reflect the radar waves in the direction they have come from - so you cant have the reflector equivalent of a flat mirror. It has to be designed to reflect as evenly as possible round the 360 degrees that a radar signal can come from. This again reduces the effective size. Imagine it as a highly polished cylindrical mirror and then think how much gets bounced back.

The you have to allow for the heel of the boat and the effect of wave motion. So it has to reflect the radar from (say) 20 deg above the horizon to 20 deg below. In effect, a cylinder with pinched ends.

finally it has to compete with other bits of metal in the boat. Its quite possible for radar waves reflected from the engine to cancel out what comes from the reflector so you get a much weaker signal sent back.

The reason for mentioning all this is that when I finally find the boat I want to buy (if, when?) I will consider an active transponder like you see on racons. Its much better to receive the signal sent by the radar, then amplify it and squirt it back. After all, field strength declines as the cube of the distance from the source so a two way trip reduces signal strength drastically. I believe there are transponders now available, but someone said to me they currently only operated on one of the two big ship radar bands.

Not so sure that one of the mags didnt do an analysis of radar reflectors and fell foul of one of their advertising customers when they ssaid there wasnt much difference in effectiveness between the reflectors they tested and a bin bag filled with crumpled up kitchen foil.

Hopefully, some techie from a radar reflector company can appear on this thread and give us the pros and cons.

 

[FullCircle]

Oh dear, you are all stoking my preconceptions about having aluminium thermal blankets in the rigging.
Come on, lets have someone who can explan this in terms that:-
a) I cant understand
and
b) in a smooth talking here's my money kinda way. /forums/images/graemlins/tongue.gif

 

[Talbot]

There are two effective (but also expensive) radar reflectors. The Firdell Blipper was the first, and then the Echomax was introduced. Either of these will provide a good radar echo on navigation radars (with the echomax being slightly the better). If you dont want to use these, then the old fashioned rain catcher style is as good as any of the others on the market, and a lot better than some. - It also meets the solas regulations of abt 7sqmetres echo area, whereas the two expensive ones produce something in the order of 10sqm.

Personnally I have a cheap tube reflector up the mast permanently, so that if necessary I can pay lip service to Solas, and I have an old rain catcher that if put up if there is fog about, but my boat has a lot more echo area above water than most raggies.

 

[roger]

Briefly; unless we test radar reflectors in position on the individual boat we dont know if they work.
When they've been up for years we dont know if they still work.
We never know if anyone on the big boats is looking at the radar or even on the bridge.
From observation on the way to the Baltic and while sailing there it seems that radar reflectors are a British obsession. There are very few used in the Baltic and the ones we see are those very thin clear plastic tubes with bits in. I've even been asked what that funny thing is on my mast above the cross trees.
In fact I have the gravest suspicions about their utility.

 

[Talbot]

Your post does have some merit, in that the polar diagram of the boat will depend somewhat on the additional reflections from the boat and mast as well as the reflector, However, the performance of the good reflectors can be measured effectively, and I remember the firdell being trialled at DERA's Aechoic chambers at DERA Funtingdon. Their claims were substantiated by the trials. In bad weather, the radar return from the body of the boat is irrelevant, because for a lot of the time it will be below the radar horizon hidden by the waves, thus the radar reflector can save your life. I have observed this frequently in the North Sea

Personally I dont really care if you dont use one, Its your life that you risk not mine!

 

[tugboat]

Go on Jim, cancel your order and get a steel boat - you know it makes sense! My radar reflector is 33 feet long - just trying to figure out how to get it vertical! /forums/images/graemlins/crazy.gif

 

[Colin24]

Jim

I work aboard a survey vessel that tows a submerged cable around. On the end of the cable we have a floating tailbuoy , it’s about the size of one of those Smart-car thingys. It has a small mast upon which we put flashing lights and a radar reflector.
Depending on the job this tailbuoy is towed either 6,000 or 8,000metres behind our vessel.

I been using this arrangement since 1979 and at that time it was normal to just have the classic aluminium square radar reflector mounted on the tailbuoy.

Since them I have tried all sorts of styles and types as and when they appear on the market (why not –I’m not paying). My non-scientific findings are that I have yet to come across a better reflector than the original old ally square. I my opinion all the subsequent supposedly improved designs (and I’m only talking of passive units) are inferior at reflecting a radar signal. Which is a pity because I think the ally one is too bulky and I like the look of some of the newer stuff, but they just do not work as well.

 

[LadyInBed]

I seem to remember a PBO test on radar reflectors ten or so years back which concluded that a bog standard octahedral radar reflector hung correctly was as good as any. Also see here

 

[Evadne]

I was on the bridge of a small vessel last year when we were steaming parallel to and about 1-2 miles from a lovely big wooden sailing boat. Not a dickey bird on the radar, until she gybed and the sail was set square on to us. A small FV at 3 times the distance showed up like a beacon. Other yachts (presumably) with reflectors were somewhere between the two, i.e. visible but not always brilliantly so.
I have for years hoisted a large ally octahedral when crossing the channel or at night or in fog. It makes us visible but it is ungainly and not suitable for permanent hoisting or strong winds. I know it works 'cos I once asked a passing steamer how we looked, he said he'd seen us at 8 miles. After talking to the chaps on the Terschelling about the sailing boat above, I am looking for a permanently "hoisted" reflector 'cos many small ships navigate exclusively on radar, and won't see me on a sunny day 'cos they never look out of the window.
The radar transponders are probably the best, but are too power hungry for someone like me so it will be a passive one, probably firdell blipper or echomax, as they are the ones others reckon are the best. I will still hoist the octahedral as before.
This is one item where I don't reckon value for money is relevant, as it provides a real and measurable level of safety in crowded waters, so go for the biggest you can permantly install.

 

[jrt]

We have a radar reflector mounted infront of the mast. Summer before last going to Cherbourg, large ferry came up dead behind. I presume it was from Poole. It did not see us. I was watching it from hull down over the horizon to within about 1 mile. At this point I decided that playing chicken with about a few thousand tons of steel was silly and flashed a torch at the bridge. It altered course sharply to starboard. The point is the mast was screening the reflector.

We have now bought and fitted a Seeme. This is an active target enhancer, mounted on top of the mast. It doesn't obscure any lights at the moment, we don't have one up there. It should produce a large blob (highly technical term) on a radar screen when we get painted. It also tells us when we have been painted.

 

[dickh]

I understood that the cheap tube type were useless; all the tests confirmed this and that the octahedral, Blipper or Echomax were best with the Echomax the best.