Radar Reflectors

Stork_III said:
The Merchant Shipping (Safety of Navigation) Regulations 2002 , unless you know better.
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Well, it's fine to quote merchant shipping regulations, but it's worth noting that the whole SOLAS issue is impenetrably complicated. There isn't a single easily accessible online source giving the actual SOLAS wording. There are lots of "advisory" publications, which say that small pleasure craft should fit a radar reflector if practicable and that boats smaller than 15m should fit the largest radar reflector you can, which is rather vague to say the least.

Then there are the retribution warnings, which say that if you happen to be in a boating accident, and if it's found you haven't fitted a radar reflector, you could be prosecuted. Which isn't especially clear.

So, should every Mirror dinghy fit a radar reflector, just in case? After all, the regulations require it if practicable, and it could be argued that it's perfectly possible to fit a radar reflector (of sorts) on a Mirror.

Or should owners of small pleasure craft just continue to use their better judgement and equip their boats with the sort of safety equipment which best matches their use of the boat, and the area in which they use it?

And if you still think the Merchant Shipping (Safety of Navigation) Regulations 2002 are the bee's knees, take careful note that they exempt fishing boats from the need to have radar reflectors. Just how mad can legislation be?
 
Just for the record - what I do ...
I have an Echomax EM230 which is one of the better passive ones. It's carried on the boat but not hoisted permanently since it's a big (though not very heavy) lump and would probably affect performance under sail (since my boat is quite small). When I feel I need it, which is not often but it's surprising how strong the feeling is in poor vis, it's hoisted up to one of the spreaders as recommended by Echomax - performance is better than when fixed close to a mast (say Echomax). Also, hoisting to a spreader means you can adjust its orientation slightly so it's vertical even when the boat is heeling a bit.

Small boats need a biggish reflector just as much as large boats do - a small passive reflector is a waste of effort and can even make the boat invisible to radar (it's possible for the echo off a small reflector to cancel that off the boat, as noted in previous posts).

I can't work out why active reflectors are so much more expensive that VHF radios which seem to me to be much more complex bits of kit. I'm waiting for a price crash. Incidentally, if I ever do get one, it will go on a pole which puts it above the pushpit - if you mount it close to (but not above) the mast there will be a shadow, and if you mount it just above the mast using the recommended bracket, it will obscure an arc of your masthead tricolour which will then be illegal (or, at any rate, unacceptable) under Colregs!
 
blackbeard said:
I can't work out why active reflectors are so much more expensive that VHF radios which seem to me to be much more complex bits of kit. I'm waiting for a price crash.
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The price is a function of the frequency they operate at. S-band radar operates between 2-4 GHz; VHF is 30-300 MHz. X-band is 8-12 GHz, if you want to cover that as well. Components that will operate at the higher frequencies are more expensive then those that operate at lower frequencies.
 
Stork III vs Bedouin

Well I jolly well hope Bedouin is right because after reading the Ouzo reports very carefully I decided not to waste money in fitting a separate passive radar reflector. I suppose I could argue that my boat is fitted with a large metal mast, and that is my reflector?

Setting these nitpicks aside, having been seriously scared this year in heavy fog in the middle of some North Sea shipping lanes, I am now definitely leaning towards fitting a Seame or similar active reflector. As well as all the AIS and radar kit so we can see what is coming.
 
Resolution said:
Stork III vs Bedouin

Well I jolly well hope Bedouin is right because after reading the Ouzo reports very carefully I decided not to waste money in fitting a separate passive radar reflector. I suppose I could argue that my boat is fitted with a large metal mast, and that is my reflector?

Setting these nitpicks aside, having been seriously scared this year in heavy fog in the middle of some North Sea shipping lanes, I am now definitely leaning towards fitting a Seame or similar active reflector. As well as all the AIS and radar kit so we can see what is coming.
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There is a North Eastern fisherman who could`nt even see the Hbr stone wall let alone another boat. Go carefully

http://www.ybw.com/forums/showthrea...-boat-Grenaa-Star-crashes-into-Tynemouth-pier
 
Resolution said:
Stork III vs Bedouin

Well I jolly well hope Bedouin is right because after reading the Ouzo reports very carefully I decided not to waste money in fitting a separate passive radar reflector. I suppose I could argue that my boat is fitted with a large metal mast, and that is my reflector?

Setting these nitpicks aside, having been seriously scared this year in heavy fog in the middle of some North Sea shipping lanes, I am now definitely leaning towards fitting a Seame or similar active reflector. As well as all the AIS and radar kit so we can see what is coming.
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I think it make sense to have a passive radarreflector if you have AIS and radar.
Otherwise if you lose power,all will fail.
Best is of course the whole lot.

We have Large Tri-Lens
AIS
Radar
Foghorn slaved by VHF
 
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RADAR reflector, Current price 12 in 12pounds 99p

Not a lot.

Just to add fuel to the fire. SOLAS is convention its not law.
Laws are unique to each flag state which adopts the convention. Each State creates its own Law. what may be perfectly leagle in the UK or on a UK boat. may not be leagle when you are in another country. There local laws may also apply to visiting vessels from other Flag States.
 
This is a rather sterile debate. The adoption of the SOLAS requirements into UK shipping law is just the minimum the government could do consistent with its stance on minimum regulation for small leisure craft. In a way it is irrelevant as there is no intention of actively policing the requirements, nor using them as a basis for prosecution, although they might be used as a reference point in an investigation into an incident. The wording is deliberately vague, effectively putting the responsibility for appropriate compliance on the skipper.

There does seem to be a consensus on the key issues. Planning is a "good thing". It is a central topic in the RYA training programme and there is plenty of guidance available to skippers on good practice in preparing a plan without adopting a prescriptive tick box approach.

There is consensus bordering on unanimity that passive radar reflectors are largely ineffective, confirmed by the Qinetic research, but it is little hardship to comply with the Solas requirements. Also consensus that the active radar devices are better. Even more consensus about the importance of avoiding ships and the aids available (AIS, Radar, Eyeball) are very effective. An active approach to avoidance of collisions is arguably far more effective than a passive one.

It is clear that the strategies that are currently used are remarkably effective as collisions between yachts and ships are extremely rare, even in our crowded waters. When you analyse the collisions that have occurred (relatively easy because most result in an MAIB report) you find there is no consistent pattern of causes and little to indicate (for example) that lack of a radar reflector had any effect on the outcomes.

This of course could mean that both radar reflectors and other means of signalling awareness by both ships and yachts are effective, but I would suggest that it is the active strategies of avoidance rather than the passive of notification are the bigger contributors to the low level of collisions.
 
Melleman said:
I think it make sense to have a passive radarreflector if you have AIS and radar.
Otherwise if you lose power,all will fail.
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In the hopefully very unlikely event that we lose all main power, we should still have a large metal mast sticking up in the air. Probably just as effective as a Firdell anyway. We should also have the handheld Garmin and Ipad to show us where we were, but not I think any AIS info.
 
Resolution said:
In the hopefully very unlikely event that we lose all main power, we should still have a large metal mast sticking up in the air. Probably just as effective as a Firdell anyway.
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Actually not true - a radar reflector is the radar equivalent of a cats-eye (do they still exist?) and something like a Firdell/echomax is the equivalent of a sphere of metal 10 feet in diameter.

Your mast is more like a mirror - may produce a good reflection at the correct angle but not much use at any other
 
AntarcticPilot said:
The price is a function of the frequency they operate at. S-band radar operates between 2-4 GHz; VHF is 30-300 MHz. X-band is 8-12 GHz, if you want to cover that as well. Components that will operate at the higher frequencies are more expensive then those that operate at lower frequencies.
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Also the much smaller market. Rightly or wrongly, the impression given by both the SeaMe and the Echomax websites is of a cottage industry, the sort of company with one boss/inventor/designer/writer, his wife doing the books, and a couple of part-timers packing orders. Compared to the economies of scale of Icom or Standard Horizon, their per-unit costs are going to be far higher.

Pete
 
Storyline said:
Is a dual band repeater worth the extra cost or is X band good enough ?
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I would say dual band, OOW should keep 2 radars on 2 different ranges and switch ranges regularly (how many actually do). They are much more likely to react to a blip on 2 radars than on one (one could be counted as random echo).

Also there are still captains out there who only like you to use one radar to save the company money.

Then again, I would be happy with AIS Class B IMHO MOST ships have AIS linked to radar and/ or there ECDIS now. Not been on one yet that would know/ bother how to filter out class B targets.

Contrary to what most people say on here ships do not normally overlay radar and chart (ECDIS). They have enough space for 2 separate screen. In my experience Radar overlay is only really useful to those who do not have space for both or do not really understand what they are seeing on the Radar.

It is to easy to miss a small radar target on the chart overlay.
 
maby said:
The trouble with that Qinetiq report is that it only measures the radar signatures of the reflectors. Mine, like most yachts, is hanging off a ruddy great lump of aluminium - it would be interesting to know if any reflector actually adds significantly to the signature of your mast.
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The report also fails because they did not measure the reflectors in use; they fed the measured cross-section into a theoretical model. In real life the things will be moving about all the time, so the shape of the RCS surface (how it varies with incident angle) will be as important as the maximum or average. For example, a reflector which had a very high RCS for incoming signals within +/- 5 degrees of the horizontal would not necessarily be a good choice for a sailing yacht.
 
I think the moral of all this is - don't go sailing in fog. If it unexpectedly becomes foggy when you're already out, get out of shipping lanes immediately and anchor in shallow water.
 
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