Do I need a radar reflector if I have radar?

[wonkywinch]

I suspect the answer is yes, but boat we're about to buy (38 foot Beneteau) has radar but no reflector.

Plan coastal cruising and thought a reflector was obligatory?

 

[dune16]

Yes, serve different purposes. How effective a reflector is another debate however

 

[Clancy Moped]

Put one up high on the spreader that way no one will see or detect it

 

[Daedelus]

SOLAS regulation 19.2.1 says that " Radar Reflector to be used if practicable "
If you want the information on how effective this site used to be quite good: Yachting and Boating World - News, Forums & Boats For Sale

It had the results of the tests Qineteq conducted for the MCA.

 

[wonkywinch]

SOLAS regulation 19.2.1 says that " Radar Reflector to be used if practicable "
If you want the information on how effective this site used to be quite good: Yachting and Boating World - News, Forums & Boats For Sale

It had the results of the tests Qineteq conducted for the MCA.

Sadly this forum's home page is extremely out of date, the watches & shoes reviewed no longer available. The articles almost a decade old. The forum however ...

 

[johnalison]

My boat has radar but no reflector - but it does have a SeaMe 'transponder' thingy. Admittedly it's one of the old single-band type but it's a good few years since I ventured far enough offshore for it to matter. I also have a useless cylinder reflector in reserve which probably does little good but makes me feel better.

 

[Daydream believer]

My boat has radar but no reflector - but it does have a SeaMe 'transponder' thingy. Admittedly it's one of the old single-band type but it's a good few years since I ventured far enough offshore for it to matter. I also have a useless cylinder reflector in reserve which probably does little good but makes me feel better.

How far offshore does one have to be to be hit by an errant fishing boat at night, or in fog, then? Disregarding how good one thinks that one might be at keeping watch.- ( not meant as an insult but we can all make mistakes)

 

[AntarcticPilot]

A radar set cannot detect another radar set, so yes, you need a radar transponder or (far less effectively) a radar reflector. I agree with those who say a reflector is of marginal utility; almost all those on the market come nowhere near the required performance.

 

[wonkywinch]

Thank you for all your input. It's a long time since I studied radar (early 70's) and I couldn't remember if transmitting a radar pulse improved visibility to other boats with radar. I know AWACS often pings aircraft weather radar but I'll look at radar transponders rather than the ugly and ineffective Ted Roger's "Dusty Bin".

Similarly, the boat has AIS receive but not transmit, so first stop is to install a transponder (probably by upgrading the B&G V50 VHF to a V60B and adding the extra antenna at the mast head.

 

[Stingo]

@wonkywinch this is very debatable: putting the 2nd AIS antenna much lower down eg on the pushpit, reduces the range that another vessel's AIS will be detected, circa approximately 10nm, which is plenty IMHO. At the mast head, depending on your mast height, that range increases to about 30nm resulting in lots of AIS noise.

 

[jamie N]

Echomax do this stuff. I chuckle at boats in my marina that are 100's of thousands of pounds more expensive than mine, with 3 bob's worth of reflector.
I've one of the above, as it is proven to be very effective, so if you're at night without an active reflector, in fog, are you going to be happier that you've saved a a bit of dosh by putting up some baco foil in a tube?
With something like this, isn't it a case of doing it properly, or don't bother?

 

[diverd]

I tested a pals boat on my radar a few years ago, with his radar on and off, and it made literally no difference, as we suspected, so feel a reflector is still needed sadly, as they are ugly and often not super effective. I am finding that the radar is really only used in fog these days, AIS being used to "see" other boats. A lot on the marina now use the Boat Beacon, an almost free virtual AIS, and for most folks coastal boating its all thats required.

 

[Stingo]

With both radar and light being waves, although of completely different frequencies and lengths, a few years ago there was an inconclusive debate about reflective tape working as a radar reflector. I'd love to know if this still has any credibility?

What do the panel think?

 

[zoidberg]

Echomax do this stuff. I chuckle at boats in my marina that are 100's of thousands of pounds more expensive than mine, with 3 bob's worth of reflector.
I've one of the above, as it is proven to be very effective, so if you're at night without an active reflector, in fog, are you going to be happier that you've saved a a bit of dosh by putting up some baco foil in a tube?
With something like this, isn't it a case of doing it properly, or don't bother?

The owner at Echomax and his family are true experts and usually quite happy to guide and advise. It's not something I do lightly, but I've trusted his judgement and bought TWO of his inflatable reflectors which give the IMO/SOLAS recommended 'equivalent response'.

Why two? Well, he had a highlighter-marked one he said he couldn't really sell so did me a 'BOGOF'. Well, wouldn't you?

I consider fog and dense rain ( it's the same stuff ) to be a hazard so try to get out of it to somewhere safer. I reckon I'm likely to be motoring in such, so don't mind dangling a big inflated sausage from my crosstrees for a while. I'll put up with the laughter, provided I'm around to hear it.

 

[KeelsonGraham]

With both radar and light being waves, although of completely different frequencies and lengths, a few years ago there was an inconclusive debate about reflective tape working as a radar reflector. I'd love to know if this still has any credibility?

What do the panel think?

Pretty unlikely. The strongest reflections are generated with reflective surfaces at right angles to each other.

Personally, I think your best chance of being seen these days is to have an AIS transceiver.

 

[AntarcticPilot]

With both radar and light being waves, although of completely different frequencies and lengths, a few years ago there was an inconclusive debate about reflective tape working as a radar reflector. I'd love to know if this still has any credibility?

What do the panel think?

None whatsoever. Radar has wavelengths measured in centimetres or tens of centimetres; light has wavelengths of 400-700 nanometres. The reflecting element has to have a length of at least a half wavelength to work at all; many times that to make an effective retroreflector. The individual reflecting elements on reflective tape are sub-millimetre in size; radar wavelengths won't see them, let alone be reflected by them.

 

[Stingo]

None whatsoever. Radar has wavelengths measured in centimetres or tens of centimetres; light has wavelengths of 400-700 nanometres. The reflecting element has to have a length of at least a half wavelength to work at all; many times that to make an effective retroreflector. The individual reflecting elements on reflective tape are sub-millimetre in size; radar wavelengths won't see them, let alone be reflected by them.

Thank you, AP, that is the most coherent explanation that I've come across.

 

[st599]

adding the extra antenna at the mast head.

That's not a good idea, the new antenna will be in the near field of the VHF antenna and drastically change it's transmission pattern. It would no longer be omnidirectional.

 

[johnalison]

How far offshore does one have to be to be hit by an errant fishing boat at night, or in fog, then? Disregarding how good one thinks that one might be at keeping watch.- ( not meant as an insult but we can all make mistakes)

Further than I have been in recent years I’m afraid. My days of crossing the seas to go abroad have passed, and I’m prepared to take the risk of crossing Harwich harbour in fair weather. It’s one of the things that the next owner of my boat can update when the time comes. In the meantime, I’m no worse off for having the old version which I fitted 23 years ago.

 

[wonkywinch]

That's not a good idea, the new antenna will be in the near field of the VHF antenna and drastically change it's transmission pattern. It would no longer be omnidirectional.

Figuratively speaking of course. I'll use an electronics firm (probably A1 Marine in Hamble) to do the fit as the manual for the V60B (easiest, most cost effective route from existing V50 AIS receive only to AIS transceive) says:

NOTE: Two VHF antennas are needed for V60-B, one for VHF and one for AIS.