Skipper ;-)
Coastal Cruiser
Returning to Sailing after many years off.... a bit daunted by it all...
Posts: 115
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Post by Skipper ;-) on May 12, 2010 12:09:40 GMT 1
I believe the regulations changed in June 2009 so it is now mandatory to have a Radar Reflector I need to fit one and I really don't know which one. It has to be PASSIVE (without 12v supply) and I want to be as safe as possible (i.e. as visible as I can be by someone elses radar).
What solutions have others used, please?
** I understand the rules changed in June 2009 - but there are few guidelines on passive Radar Reflectors for boats unded about 15metres ** There was a practical test in Sailing Today in December 2009 - did anyone read it? ** There was a MIAB test done after the Ouzo disaster. Loads of technical information.... can anyone understand it?
It appears the 'Davis' type (interlocking pieces in a ball shape, it usually can be dismantled to flat for storage) has the best response from other ships. Do others agree?
It also seems that Angle of Heel effects any Radar Reflector a lot. And the Davis Type type are less prone to effects of heel if mounted in the 'rain catcher' position.
There are a constant stream of huge ships in the Solent. A few months ago I was reminded how close I was and I feel a Radar Reflector is good for those times - see and be seen. Also, some peace of mind when anchored or the boat is unattended.
What do other people think? Any ideas...? What do others do?
Regards to all
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Post by NigeL on May 12, 2010 12:22:47 GMT 1
Interested to know what rules changed to say you MUST have a Radar Reflector ?
They are as far as I know - still advisory, not compulsory.
I know that unofficially - you are required to have one for certain association, club, regatta events as part of on-board inventory - but that's it.
The 'rain-catcher' is probably as good as any other passive reflector. I know that various reviews have shown the tube types to be near useless ...
It has to be looked at in relation to the sea around you. A wave with a 'face' presented to the radar signal will bounce back an echo - usually referred to as sea clutter. That wave will probably be bigger or more face than your yacht. Your passive reflector only gains really by having it at height, so waves, swell etc. don't hide it. But it's overall cross-sectional area is very small ... again the wave is bigger.
I'm always amazed that reviews, comparisons of reflectors in mags ... various 'experts' ramblings seem to forget the above simple maths and facts.
I have a 'rain-catcher' reflector and rarely hoist it. I do know that my GRP sail boat gives a target in reasonable weather at a reasonable distance, as verified by ships I've asked on VHF. But that assumes their radars are set-up well and observer is good.
That is another matter that tends to be ignored. Ships watchkeepers have it drummed into them that EYEBALL conning is primary and radar is an aid. It does well to take that in mind ...
I speak as an Ex Senior Bridge watchkeeper.
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Post by Ken.P. on May 12, 2010 13:35:53 GMT 1
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Post by ggt on May 12, 2010 13:43:28 GMT 1
It's a SOLAS V requirement to fit a radar reflector... one of the few obligations that the requirements place on leisure vessels: handy leafletThis is from 2002 I think and I'm not sure what, if anything, changed last June. Small passive radar reflectors don't always do much to improve your radar signature so by all means fit one but don't assume it means that other vessels will see you on radar. As an example, lots of small commercial RIBs and launches have a tubular/MOBI radar reflector despite these being generally acknowledged to be near useless in most tests... they are popular because they are cheap and convenient to fit and fulfil the obligation to have a reflector, not because they work. As to what others do, I've a big Davies catch-rain because it did well in one test or other but it's a pain to mount and I decided it made no real differencce so it has lived in my workshop for some years now... p.s. welcome to SBC by the way ;D
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Post by geoffwright on May 12, 2010 13:55:50 GMT 1
I fitted a Firdell Blipper reflector that I found on EBay, complete with brackets, for about £35. These have been 'overtaken' by Echomax, but I believe they are almost identical in specifications. Most of the yachts in our part of the Tamar have mast fitted reflectors, and from my 'experience' of crossing the Channel, I personally think they do work, subject to the conditions as Nigel rightly says.
Again, as Nigel says, the Mark One eyeball is the best tool for the job!
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Post by NigeL on May 12, 2010 14:17:28 GMT 1
There is nothing here that says MUST by law carry.
It is all 'where practicable' and some leaflets etc. word cautiously as close to obligated as they can get without crossing that legal line.
SOLAS in fact is not REGULATION by law - all SOLAS are recc'd and accepted by Maritime Authorities, BUT before you all jump on me - woe betide anyone who fails to abide by them. THAT's the killer with SOLAS. You can in fact ignore SOLAS - but in event of incident or accident - you will pay the price in court as General Maritime Practice - the rule of Precedence - takes over. I know this from actual experience of a case.
SOLAS in force by law is OLD ... all the later ones are amendments and pending full International Acceptance and law. But all mariners are expected to comply.
I know you can pull up reference after reference that 'appears' to argue I'm wrong ... but again - I say : they toe the legal line of not quite saying legally binding....
SOLAS has a really difficult time of it, for many reasons but 2 are main. IMO is not so respected as many would have believe by various national authorities... we won't go into that now as it's a large subject..... and IMO is one of the driving bodies of SOLAS. Second it needs all maritime nations to agree to any changes and to ratify. Ratification takes years. So to get around that they issue as reccommendations and appendices etc. with proviso that they be implemented asap and written into SOLAS fully later when all agree.
It took 20yrs to get USA to agree to change of IRPCS in the 70's ...
It took similar to try and get IALA buoyage introduced ... and what happened ? USA implemented red to starboard !
All I'm trying to illustrate is that SOLAS etc. is not cut and dried exact. It is really a minefield of resolutions.
Sorry for rant ...
Me ? I will not argue with SOLAS, but still I usually don't 'fly' my reflector.
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Post by Ken.P. on May 12, 2010 16:15:15 GMT 1
Can't see anyone arguing about it being compulsory, leaflet is pretty clear.
I'm struggling to find somewhere to mount the thing, top of the mast is looking like the best option as I've got no standing rigging.
A steaming light will be going up there soon, once I've figured out a way of getting a wire up (or down) the inside of the mast. It's keel stepped, but hinged near deck level and both pieces are plugged with wood at the joint. Can't run wire up the outside of the mast as it wouldn't last long with most of the running rigging being around the mast.
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Post by NigeL on May 12, 2010 17:16:51 GMT 1
Can't see anyone arguing about it being compulsory, leaflet is pretty clear. I'm struggling to find somewhere to mount the thing, top of the mast is looking like the best option as I've got no standing rigging. A steaming light will be going up there soon, once I've figured out a way of getting a wire up (or down) the inside of the mast. It's keel stepped, but hinged near deck level and both pieces are plugged with wood at the joint. Can't run wire up the outside of the mast as it wouldn't last long with most of the running rigging being around the mast. Page 2 of the Leaflet deals with radar reflectors and again repeats "if practicable" .....
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Post by geoffwright on May 12, 2010 17:23:52 GMT 1
A steaming light will be going up there soon, once I've figured out a way of getting a wire up (or down) the inside of the mast. Hi Ken, I had a similar problem, I will PM you with details. Geoff
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Post by Ken.P. on May 12, 2010 17:58:36 GMT 1
Page 2 of the Leaflet deals with radar reflectors and again repeats "if practicable" ..... That's what I meant Nigel, not too clear was I.... I also said the same in my first post.
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Post by Ken.P. on May 12, 2010 17:58:44 GMT 1
Thanks Geoff, reply sent....
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Post by Len Baddeley on May 12, 2010 20:11:45 GMT 1
Re the test of passive radar reflectors the Firdell/Echomax blipper came out on top the Plastimo came bottom. The problem with the active reflector is that they only operate on one band not both bands. Len.
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Post by NigeL on May 13, 2010 7:45:30 GMT 1
Page 2 of the Leaflet deals with radar reflectors and again repeats "if practicable" ..... That's what I meant Nigel, not too clear was I.... I also said the same in my first post. Sorry when reading your post before - it seemed you were saying it was compulsory ... my bad Latvian English !!
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Post by NigeL on May 13, 2010 7:50:05 GMT 1
Re the test of passive radar reflectors the Firdell/Echomax blipper came out on top the Plastimo came bottom. The problem with the active reflector is that they only operate on one band not both bands. Len. I did hear that one co. was looking at creating a dual band active job. But let's go further ... most Racons are 3cm ... so S band radar doesn't have the ID racon signal displayed. If you go for 3cm - you'll be in the majority league in N.Europe, 10cm in USA ...
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Post by Ken.P. on May 13, 2010 7:58:17 GMT 1
No prob Nigel.
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Post by Len Baddeley on May 14, 2010 10:34:43 GMT 1
Echo Max no make a dual band active reflector, both X and S band, the single band units only work on X band, I belive S band is used on military ships mainly but they would also use X band too. Len.
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Post by NigeL on May 14, 2010 11:24:30 GMT 1
Echo Max no make a dual band active reflector, both X and S band, the single band units only work on X band, I belive S band is used on military ships mainly but they would also use X band too. Len. X (3cm) and S (10cm) are both used on commercial ships. 3cm is better definition of target due to less side extension beam width. But suffers more from seastate interference and fog / rain. 10cm has a better penetration and return in difficult conditions such as fog, rain and sea clutter but is poor in land definition for nav. 3cm due to length of cabling usually fitted with wave guide to transmit signal to antena, 10cm is not so bad and uses heavy duty cable. Europeans use 3cm mostly while US influenced tend to go for 10cm ... yep - its' really that daft ! But most ships are equipped with both types to cover all possibilities. They even can interswitch antena's from one set to another even though wavelengths are different. This was useful on the gas ships I sailed on when we needed max return for nav when in Palawan Passage on one side going up ... other side coming down !! When looking at ships antena ... the 3cm is the more closed smaller of the rotators ... 10cm often looking more open framework style and larger.
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Post by stephen on May 15, 2010 14:43:20 GMT 1
Ok I use the round tube sort. I looked at the different types and looked at how they catch sails. Then I spoke to peeps who work on the big ships. It seems rarda works in a stright line. So my boat is 18 ft the top of the mast is at most 23 ft above the water line. So in most cases in the solent the big ships rarda will pass right over the top of me. I will go by colregs and take avoiding action where needed. It is an accepted rule of thumb in the solent that the big ships restricted in their ablity to manover or constraned by draft. Its no good shouting at upteen 100s of tons of container ship that "I am the stand on vessel" I used to take scouts out on a contesser 34 and one of the thengs we used to show scouts was how long it took to stop....the average container ship needs five miles.
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Post by NigeL on May 15, 2010 15:41:59 GMT 1
Ok I use the round tube sort. I looked at the different types and looked at how they catch sails. Then I spoke to peeps who work on the big ships. It seems rarda works in a stright line. So my boat is 18 ft the top of the mast is at most 23 ft above the water line. So in most cases in the solent the big ships rarda will pass right over the top of me. I will go by colregs and take avoiding action where needed. It is an accepted rule of thumb in the solent that the big ships restricted in their ablity to manover or constraned by draft. Its no good shouting at upteen 100s of tons of container ship that "I am the stand on vessel" I used to take scouts out on a contesser 34 and one of the thengs we used to show scouts was how long it took to stop....the average container ship needs five miles. Ok - lets continue the info ... The radar beam is actually not a straight line. It is like a narrow petal fan with two smaller side lobes... the central one is focused as narrow as possible but is fan like in it's character, so gets wider with distance and weaker. www.radartutorial.eu/06.antennas/an05.en.htmlVertically the central fan has a considerable angle to it and can be likened to a lighthouse beam. So as long as your boat is above the visible horizon - you will be picked up. One of the biggest problems with width of the beam. When the beam crosses a headland or point it paints from the start of beam hitting it, till last of beam width hitting it ... we call this beamwidth extension. In some cases this can cause a narrow channel opening in a breakwater to not appear as the two ends appear to be connected as one. Not until you get close enough for angle of opening to exceed the beamwidth angle will it appear to open. When running along a coastline, headlands will paint further out to sea than real due again to same reason. In fact get close enough and side lobes can have effect as well increasing that error. This is all taking me back to younger years of radar courses etc. !! Somewhere I have my old radar course book ... will dig it out.
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Post by ood on May 15, 2010 16:56:42 GMT 1
........but like Stephen says, not much point arguing the toss, on who is the stand-on vessel . . ps my blood pressure is to high already pps any chance of turning the club burgee into a reflector burgee, please?
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