Congratulations QinetiQ and MAIB

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fluffc

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[applaud]
I would like to congratulate Qinetiq and MAIB for producing a concise and well executed experiment and document about the performace of yachting Radar reflectors.

The putting into the public domain of an independent and unbiased test of yachting (safety) equipment is to be congratulated.

It was good they didn't say 'this is the best' etc etc, but presented all the information they had assimilated clearly, so that we can make up our own minds.

In this day and age of commercial interest in such tests (see 'Diesel additives' test recently carried out by PBO), it is great that at least someone has remained level-headed and above it all.
[/applaud]
 
I endorse the above post fully. This is what the MAIB is best at.

Publication of the crucial awareness of radar limitations - held by only a few with specialist training - is long overdue. I trust the 'refuseniks' will keep in the background, while this stuff is absorbed into the consciousness of the majority.

/forums/images/graemlins/wink.gif
 
I agree but was surprised to see (if I am interpreting the report properly) that the octohedral type is not quite as useless as I had been lead to believe when not mounted in the "rain catch position" also the old firdell blipper seemed to be better than the octohedral generally which I was also surprised to see as I thought it would be the other way around... Good news though as I have got one!
Only read the report quickly though... have I got it right?
 
I was going to buy one of the tube type reflectors, I certainly won't now. In the short term I will drill new holes in my Plastimo Octahedral to get it to sit in the catch rain position.

What we really need now are some seame competitors to enter into the market to bring the price down of the active reflectors. That has to be the way to go - backed up by a passive reflector.
 
One more thing that worries me, having re-read the report. If I understand it correctly when you get within a couple of miles to a Ship they pretty much can't see you on Radar because of sea clutter.

I was of the simple belief that the closer you got the more likely you would get picked up. Lots of lessons coming out of this tragedy!
 
It seems to me that if you are going to buy a SeeMe or similar you might as well buy a radar as the costs of a low end set and a SeeMe are comparable. Whilst all this active stuff is great for enhancing a radar image, it is still *passive* collision avoidance.

Having had two very near misses in the murk with radar refectors and a biggish (38') boat, I, for one, will no longer go across the channel without a functioning radar set.
 
Having read the report with great interest I would still appreciate forumites' advice. I have recently fitted a Sea-Me target enhancer and am very pleased with it - not least because it warns me when I am being "illuminated". However, since the Sea-Me system is totally ineffective against S band radar, should I continue to hoist a small octohedral reflector; or will this just give a false sense of security?
 
The report says:

"The report covers measurements taken at X-Band (9.41GHz) only. SOLAS Chapter 5
requires that all vessels over 300 tonnes carry an X Band radar and all ships over 3000
tonnes to also carry an S Band radar as well. All commercial shipping should be at
least using X Band radar."

So, absent the problem of the watchkeeper being in the loo, or making himself some toast (or some other distraction), X band response is probably as good as it gets.
 
It can't make things worse

And if you have it there is no cost - so why not.

Belt, braces and a length of string.
 
I, too, applaud this report. It is thorough, well presented, easily understood and should be pinned up on every yacht club noticeboard.

In fact, it doesn't actually add much to what we already know about radar reflectors and the results are pretty much in line with reports that have appeared in YM and other mags over the years. But it is a timely focus on the limitations of all the current models and also highlights some things that are not generally known; we all know, for example, that there are holes in the returns depending on angle, but the holes dependant on range are a bit of a shocker.

However, real life exercises we have carried out suggest that any reflector (except the thin tube things) at worst adds something to your radar profile and, at best, gives it a real boost. So don't throw yours away just yet.

The finding that most surprised me, and was slightly contrary to the results we obtained the last time we covered this subject, was the comparatively good performance of the humble octahedron. Personally I am delighted because I won't, now, go out and buy an expensive enclosed array type. Sea-me, however, remains on my wish list together with MARPA radar.

I also agree that it is worrying that no passive reflector meets current or future standards. It is definitely time for some serious research and more competition in the field of active transponders.
 
Well I take it to mean that a gert big ship is looking down at you which means the angle between the transponder and your reflector is already quite big before you even heel, but wondered if the angle of heel might actually help close in if the ships transponder is then looking at it at 90 degrees. Of course if thats true from the other direction, or on the other tack a ship might not see it at all.
I think it is clear though that to get a good reflection from a near target a radar transponder needs to be mounted low down and the reflector high up. As most big ship radars are pretty high up thats probably why you are lost in clutter when close. Do other forumites read the results the same way?
 
[ QUOTE ]
It seems to me that if you are going to buy a SeeMe or similar you might as well buy a radar as the costs of a low end set and a SeeMe are comparable. Whilst all this active stuff is great for enhancing a radar image, it is still *passive* collision avoidance.

[/ QUOTE ]

I agree. it doesn't matter what active or passive radar reflector you have got if a ship's watch keeper is more interested in doing something other than closely watching his radar and looking out of the window. Unless you have taken active steps to alert a ship of your presence and get an appropriate response, the yachtie should be concentrating on all means of active collision avoidance and radar is a prime tool.
 
I find it quite interesting that several Forumites, including the redoubtable JJ have the Seame on 'their wish list'.

And yet I am sure thay have liferafts, lifebuoys and MOB gear.

Where a piece of equipment is regularly denigrated in the Yachting press as less than 'fit for purpose', why buy it? By that I mean the cheaper radar reflectors.

HWMBO pushed for a Seame when we were first fitting out the boat, and I for one am very glad.

We came round Cape Finisterre a couple of year ago in quite horrid conditions, and quite close to the shipping lanes. Two ships altered course to check on us, which for me was comforting.

People who have the Seame can be seen on a radar as a HUGE blob, like a racon beacon.

While I believe that many ships pay lip service to proper watch systems (I have seen shipping in the channel with nobody on the bridge), I do believe that they keep a radar watch, if only to maintain station in the shipping lanes. So at least we get seen.

IMHO a Seame is as good a piece of safety equipment as you could buy.

We crossed the channel last weekend and having had our liferaft stolen in the winter, were faced with getting a new one. Of course the exact one we had taken is no longer available and its replacement is much more expensive.

However, as I like comfort, I would have chosen a raft with a nice galley, a couple of bunks and a loo.

Actually the one we chose was quite expensive (an ISO standard)- we had seen cheaper ones in Marine Superstore & I wouldn't like to spend a night at sea in one of those. So it may well have full mod cons. at that price!!

I just have this feeling that in the last resort I would be very p**ssed off if I was sitting in a cheap liferaft having been run down by a ship that didn't see us, wondering if it would hold together long enough for us to be picked up in reasonable condition, just to save a few pounds.
 
Well, actually, I don't have a liferaft - I hire one for passages I think need it - remember I sail an unsinkable (yes, I know!) catamaran, which is its own best liferaft in many ways. Also, the only charging system I have for my service batteries are a pair of large solar panels - they cope with autopilot, GPS/plotter, nav lights, cabin lights and sailing instruments for an overnight passage but it can be marginal later in the season if the weather's been cloudy during the day.
 
A new SeaMe???

I'd be astonished if, post-Ouzo reports, the new product development departments at Raymarine, Silva, Nasa et al, aren't beavering away to make X & S band active transponders to compete with SeaMe which has had the market to itself for years. So now may not be the time to buy a transponder. Earls Court/Excel might be interesting though.

Sort of similar situation to that which existed with EPIRBs ten years back. Very few to choose from, and very expensive. Now, with more competitors, they're smaller, cheaper, incorporate GPS (some) and have better battery lives. Bring on the clones!
 
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