What do I do about my radar reflector?

[rachapman]

As the owner, like so many others, of a boat with a thin tube radar reflector screwed to the mast, I had previously assumed it was doing what it said on the tin ( or packaging). The Quinetic report is a bit of a shock. I'm particularly worried because we do fairly frequent X-channel trips across the Dover Straits with big ship avoidance usually the main problem. Not happy about being invisible on their radar. As an interim measure, I've bought a big octahedral while I think about the c/b of an active target.

Thinks:
Where to locate the octahedral- on the backstay seems to be the most appropriate- unless you know better?

Dover PC contacted me when we were off St Margarets last year when I circled to retrieve my hat (failed). We must have had a good radar signature. On occasions when we have contacted ships to ask about their intentions ' We have you on radar' has been a consistent response.

Should I remove the 'useless tube' reflector before using the octahedral, ie are there probable interference effects?

Should Platimo et al continue to be able to sell the 'thin tube' products as radar reflectors?

 

[Greenwichman]

Your call what to do with your reflector, of course!

Like you, I sail across the Dover Strait. I choose not to fit a passive reflector, which after more than 30 years at sea professionally I know to be useless.

I am toying with fitting a 'Sea-me' active transponder (google it for details), but am put off because the price is still high (£500 - ish) and the device only operates on X band, whereas many ships use ARPA on S band.

Because of these issues I choose to cross the Channel in good visibility and in daylight, which is perfectly feasible via Ramsgate.

If caught out at night I use a powerful light to iluminate the sails, keep away from the ahead sector of anything within 3 miles or so, and obey Rule 10 (TSS) to the letter.

I try to avoid low visibility at all costs.

I keep a fold-flat reflector in the cockpit locker to satisfy any bureaucratic checker that I am in fact carrying one.

 

[macd]

"Should Platimo et al continue to be able to sell the 'thin tube' products as radar reflectors?"

Fit for purpose? Seems arguable, at best.
Mind you, if RCD doesn't seem to be policed (and I'm not urging that it should be), what chance a 2 foot bit of plastic?

On the other hand there's the 'if it looks too good to be true...it probably isn't' approach. Just look at one of those things and tell me, hand on heart, that you think it gives a bigger blip than the mast it's attached to (with apologies to mobo owners...not trying to be exclusive)

 

[Bergman]

The fact is that none of the passive reflectors fully meet the specification so I suppose all of them should be taken off the market.

Which I guess means that using any of the existing reflectors means you are breaking the law, and not using any of the reflectors means you are breaking the law.

Not sure what the rule is for an active transponder, suspect that it isn't a "reflector" since it doesn't work on "S" band. So I guess you need a reflector as well.

Not sure what the licensing situation is with these things - I assume they need a CE mark but whether or not they are legal to xmit on x band I'm not sure. Presumably you have to get Ofcom to put it on your license, but can't think what as if there isn't a specific transponder license.


Clearly this is EU legislation

Perhaps we'll get ASBOs

 

[franky]

All this discussion regarding the SeaMe presupposes that the other vessel is looking at his Radar.
Similarly an AIS transponder on the small vessel makes the same assumption.
An AIS receiver on the small vessel will at least display those vessels which are required to have a transponder (over 300 tons if memory correct) and a Radar set willl help to display the rest.

 

[Bob_Ranft]

I'm also toying with the purchase of a SeaMe transponder, also concerned that it only works on X band and that my passive reflector can give good results in ideal conditions, followed by very indifferent results in less than ideal conditions.

Can anyone please explain why they can make an active transponder that works on X band - but there seems to be no such animal that works on S band. Is it price, is it technically not possible, will it contravene rules and regulations etc.

 

[Twister_Ken]

>Can anyone please explain why they can make an active transponder that works on X band - but there seems to be no such animal that works on S band. Is it price, is it technically not possible, will it contravene rules and regulations etc. <

I think, personally and with no knowledge of the companies involved, it's because the Sea Me market, pre-Ouzo, was very small. Post-Ouzo, it's suddenly become much bigger, and it's a reasonable bet that other marine electronics companies' R&D people are beavering away at a second generation active transponder, with X & S band capability. Maybe wait for the autumn and winter boat shows before going 'active'?

 

[bilbobaggins]

I've used the Sea-Me kit on three sailboats over the past few years, and been relieved to do so. 'It does what it says on the tin...' Corner reflectors simply don't, and that's been known for decades.

However, I seem to recall the business is - or was - a 'one-man band', owned and run by a very capable but semi-retired electronic engineer ( prior apologies if my memory is not quite accurate! ),Peter Munro.

It is probable that he identified what he thought was the most 'do-able' technical solution, and marketed that - with little funding for R&D, in traditional British boffin style. He may well be developing a dual-band device - it is certainly 'do-able' - so why not ask him about what you want? That takes only an email.....

I do recall that he DIDN'T get RYA support or encouragement, for some specious and pompous reason, which was something of an economic setback at the time.

I'm afraid it takes - as in other walks of life - a tragedy to shift 'official' opinion away from complacency to demands for action.

/forums/images/graemlins/shocked.gif

 

[vyv_cox]

<< Dover PC contacted me when we were off St Margarets last year when I circled to retrieve my hat (failed). We must have had a good radar signature. On occasions when we have contacted ships to ask about their intentions ' We have you on radar' has been a consistent response. >>

You may be highlighting one of the drawbacks of testing reflectors in a chamber. I have been informed that the biggest return of an actual boat is the 'hole in the water', regardless of the passive reflector in use. Presumably this decays significantly in rough conditions. On several occasions I have been aboard my own and other boats and been assured that we were visible on radar, despite having no passive reflector.

I carry a 2 inch Mobri reflector on the backstay where, I have always assumed, it is totally useless. My viewpoint is that it is there to satisfy any possible query from European officialdom, whereas the business of keeping away from collisions is entirely my own.

 

[Slow_boat]

It's strange, a lot of years ago I was on a team evaluating RIBs for military use. We tried all sorts but try as we may, we couldn't stop the things showing up on radar.

Now they're saying that even with a purpose built radar reflector modern radar couldn't see them?

 

[pandos]

All of this testing brings these thoughts to mind.

Why when i look at my radar am I frequently able to see small fishing vessels and nav marks miles away that do not use active transponders.

If the regular metal ones are ok except at heel can they not be hung from the crosstrees and tied so as to be vertical at heel. One on each side of the mast and one up the backstay all in the Catch rain position would seem to be a pretty fair compromise.

Why are there so few manufactures of active reflectors. ( and why are they so expensive) I think €750 for something that is guaranteed for 1 year is relatively expensive ) Is the technology patented??.

Volvo having developed seatbelts, released the designs to the whole world in the interests of mankind.

Personally Having read both of the radar reflector reports and the MAIB report into Ouzou and Wahikuna, better Mast head lights and use of own radar/ training may be better use of money than active reflectors.

A waterproof/handheld vhf in the cockpit or in your pocket epirb and a PLB for when all else fails.

 

[Oldhand]

[ QUOTE ]
I'm also toying with the purchase of a SeaMe transponder, also concerned that it only works on X band and that my passive reflector can give good results in ideal conditions, followed by very indifferent results in less than ideal conditions.

Can anyone please explain why they can make an active transponder that works on X band - but there seems to be no such animal that works on S band. Is it price, is it technically not possible, will it contravene rules and regulations etc.

[/ QUOTE ]

S-Band is a much lower frequency than X-Band and thus has a longer wavelength. By the laws of physics a longer wavelength requires a larger antenna to radiate it efficiently. There is a rumour that there is a combined X & S-Band SeaMe in development but it will be twice as long, heavier, use more power and be approximately twice the price of the current X-Band model. Does that explain why the current model is X-Band only? I think so.

 

[billcowan]

what to do about radar reflector? FORGET IT

What do I do? Echomax (the least useless) hanging vertical from flag halyard when in dense fog.

On my bigger boat, blipper (2nd least useless) stuck to mast where it was when I got the boat. When in poor vis, turn on radar.

Incidentally, now radar has gon all integrated with chartplotters and stuff, you can get a perfectly good Rayathon CRT setup on e-bay for less than the cost of a SEE-ME and a lot more use.