Frontier
Well-Known Member
Do you have a radar reflector on your mobo
Do you have a radar reflector on your mobo
- Thread starter Frontier
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SkipperMarv
Well-Known Member
If you are out on the boat some day, look at your radar, how many boats can you see with your eye, that don't get picked up by radar???
Now consider being caught in fog on your boat that isn't fitted with a reflector. Can everyone see you???
I guess you'll guess we have a reflector fitted /forums/images/graemlins/smile.gif
Now consider being caught in fog on your boat that isn't fitted with a reflector. Can everyone see you???
I guess you'll guess we have a reflector fitted /forums/images/graemlins/smile.gif
duncan
Well-Known Member
well I have a relatively cheap radar (jrc1500 mkI) and I can, and do, pick up most navigation marks (including withies) let alone all craft I have ever seen by eye.
down sides are if visibility is restricted by really really heavy rain I wouldn't make the same claim
furthermore the people most likely to hit me in open water and poor conditions are the craft I can most definitely see (and take appropriate action) on my radar and the ones I am most concerned about are in inshore waters, good weather and bad fog - which don't have radar anyway!
Finally, with the exception of one yacht in Poole once, I haven't noticed any significant difference in the radar signature from mast mounted 'radar reflectors'.
None of this should be taken as any reason not to install a radar reflector of course. If it is practical to do so you are required under Solas V regulations to do so. Unfortunately in my case I find it impractical.
down sides are if visibility is restricted by really really heavy rain I wouldn't make the same claim
furthermore the people most likely to hit me in open water and poor conditions are the craft I can most definitely see (and take appropriate action) on my radar and the ones I am most concerned about are in inshore waters, good weather and bad fog - which don't have radar anyway!
Finally, with the exception of one yacht in Poole once, I haven't noticed any significant difference in the radar signature from mast mounted 'radar reflectors'.
None of this should be taken as any reason not to install a radar reflector of course. If it is practical to do so you are required under Solas V regulations to do so. Unfortunately in my case I find it impractical.
Solitaire
Well-Known Member
SOLAS V regulations actually requires all boats to be fitted with radar reflectors. Regulation V/19 requires all small craft to fit a radar reflector "if praticable". If your boat is more than 15m then you should fit a relector that meets the IMO requirements. If less than 15 metres then you should fit the largest radar reflector you can.
The MCA issue a leaflet about the subject.
The MCA issue a leaflet about the subject.
Robin
Well-Known Member
Stealth mode
Hi Duncan
Partly to answer your post but also general comments.
In thick (like 25m) fog off North Head buoy we picked up a head on fast moving target but not before it was just 3/4ml away. We guessed it was a fast mobo without radar as it was still coming straight at us. We had the NH buoy immediately on our port bow and wanted to turn for Poole, we were making just 3-4kts under engine as there were lots of boats around and difficult to predict. This prat eventually passed us inside the 25m vis range, a 25ft sport cruiser doing I would guess around 25kts, 4 in the cockpit, 2 facing aft 2 facing forwards with the helmsman on the mobilephone. They had no radar reflector, nor radar.
The point is that yes we too can pick up withies and even pot marks in calm seas but this mobo was approaching head on so I suspect his engines, which are a good radar target, were very low down as seen (or nearly unseen) by our radar and his bow/foredeck shaping was like a stealth fighter's, hence our first view was not until he was just 3/4ml away, just a couple of minutes but very frightening ones.
In rough weather fog off Ushant we came up on a small wooden boat with wooden mast, hove to. He was only visible on radar on 0.5ml range setting and after re-adjusting the gain/tuning and that was after we 'came across' him by eyeball first!
Please please fit a reflector guys, it may not be very good but it sure beats nothing!
Robin
Hi Duncan
Partly to answer your post but also general comments.
In thick (like 25m) fog off North Head buoy we picked up a head on fast moving target but not before it was just 3/4ml away. We guessed it was a fast mobo without radar as it was still coming straight at us. We had the NH buoy immediately on our port bow and wanted to turn for Poole, we were making just 3-4kts under engine as there were lots of boats around and difficult to predict. This prat eventually passed us inside the 25m vis range, a 25ft sport cruiser doing I would guess around 25kts, 4 in the cockpit, 2 facing aft 2 facing forwards with the helmsman on the mobilephone. They had no radar reflector, nor radar.
The point is that yes we too can pick up withies and even pot marks in calm seas but this mobo was approaching head on so I suspect his engines, which are a good radar target, were very low down as seen (or nearly unseen) by our radar and his bow/foredeck shaping was like a stealth fighter's, hence our first view was not until he was just 3/4ml away, just a couple of minutes but very frightening ones.
In rough weather fog off Ushant we came up on a small wooden boat with wooden mast, hove to. He was only visible on radar on 0.5ml range setting and after re-adjusting the gain/tuning and that was after we 'came across' him by eyeball first!
Please please fit a reflector guys, it may not be very good but it sure beats nothing!
Robin
jfm
Well-Known Member
[ QUOTE ]
If you are out on the boat some day, look at your radar, how many boats can you see with your eye, that don't get picked up by radar???
[/ QUOTE ]
Zero. In fact we find the opposite. How many does the radar see that we can't yet see with eyes? (And nothing worng with eyesight!). Answer, lots. Radar picks stuff up several miles away and you cant see a small dayobat at that distance on a hazy day with your eyes, but the radar can
If you are out on the boat some day, look at your radar, how many boats can you see with your eye, that don't get picked up by radar???
[/ QUOTE ]
Zero. In fact we find the opposite. How many does the radar see that we can't yet see with eyes? (And nothing worng with eyesight!). Answer, lots. Radar picks stuff up several miles away and you cant see a small dayobat at that distance on a hazy day with your eyes, but the radar can
Gludy
Well-Known Member
If you have your radar on does not that a;so act as a reflector?
jfm
Well-Known Member
I'd guess nope. Its signal would not be recognised by the transmitting radar (even if the same frequency) becuase it would be so out of phase.
And if it did the target boat would show as half the actual distance away - so you can guess they will have engineered them so this doesn't happen
And if it did the target boat would show as half the actual distance away - so you can guess they will have engineered them so this doesn't happen
duncan
Well-Known Member
nope - one of those myths I believe.........
DAKA
Well-Known Member
Sorry to cause a ball' up but I voted yes and as I hit the button the little tinker switched on me to vote no /forums/images/graemlins/mad.gif
I am surprised by the number of apparent boats with no protection anyone else had a last minute uncontrolled swing that could explain the unexpected result ?
I am surprised by the number of apparent boats with no protection anyone else had a last minute uncontrolled swing that could explain the unexpected result ?
duncan
Well-Known Member
Re: Stealth mode
not disagreeing the general gist of your post Robin however if this prat (your words!) was going to get you there wasn't a lot you could do about it reflector or not - he's as likely to make a sudden last minute course change either way to avoid someone else as he was to hold a course!
where you were in the conditions and traffic you describe I would be on 0.5 / 0.75 mile range and in Poole Harbour and it's approaches it will be 0.5 too. On that basis I would have seen him, or any other craft, equally well without a reflector. This is of course very different to 6/12 mile mid channel poor vis use and I tried to make that point clear in my post.
not disagreeing the general gist of your post Robin however if this prat (your words!) was going to get you there wasn't a lot you could do about it reflector or not - he's as likely to make a sudden last minute course change either way to avoid someone else as he was to hold a course!
where you were in the conditions and traffic you describe I would be on 0.5 / 0.75 mile range and in Poole Harbour and it's approaches it will be 0.5 too. On that basis I would have seen him, or any other craft, equally well without a reflector. This is of course very different to 6/12 mile mid channel poor vis use and I tried to make that point clear in my post.
duncan
Well-Known Member
what unexpected results?
would expect similar response to polls on 'anchor balls', 'current almanacs' and 'spare fully rigged anchor rodes onboard'.
would this make me a cynic or a realist? /forums/images/graemlins/wink.gif
would expect similar response to polls on 'anchor balls', 'current almanacs' and 'spare fully rigged anchor rodes onboard'.
would this make me a cynic or a realist? /forums/images/graemlins/wink.gif
KevB
Well-Known Member
I seem to remember a test done by MBM/MBY some time ago on passive radar reflectors. I think the outcome was most don't work and the odd few that did, did very little. Maybe I'm confused?
Gludy
Well-Known Member
I have a reflector fitted but admit had fallen for the myth about the radar itself acting as a detector ... nice to learn.
clivew05
Well-Known Member
I will have a radar reflector from this weekend - however I was one of the gullible mugs that was told when I bought the boat (as I had a reflector on my old boat ) that I did not need one as the boat was fitted with RADAR and this would reflect as well - so no need .. I have since been corrected by the kind forumites here and will now purchase one this weekend and fit it ready for this season ... I tend to go a lot of places where there is traffic - and would not want to get hit by a biggie because I was invisible ...
Clive
Clive
DAKA
Well-Known Member
I have two, one of those neat and tidy things permanently attached and the good old fashioned fishing boat type that comes out top in all the tests that is hoisted in fog.
I cant believe half dont have them, equally although you dont carry one I do know you carry a whacking great BBQ on board big enough for an army which will act better than any pucker reflector /forums/images/graemlins/wink.gif
Also deduce from the conditions you cross in that your engines will be far from hidden below the waterline and more likely 2 ft above the crests /forums/images/graemlins/cool.gif
When my vote got switched I thought others too could have been changed ?????????????????????????????
I cant believe half dont have them, equally although you dont carry one I do know you carry a whacking great BBQ on board big enough for an army which will act better than any pucker reflector /forums/images/graemlins/wink.gif
Also deduce from the conditions you cross in that your engines will be far from hidden below the waterline and more likely 2 ft above the crests /forums/images/graemlins/cool.gif
When my vote got switched I thought others too could have been changed ?????????????????????????????
clivew05
Well-Known Member
Oh and incidentally /forums/images/graemlins/blush.gif I have made several trips across the Thames estuary with my radar on doging big ships in the fog - under the impression that they CAN see me as I had my radar on ... so must be pretty lucky that I have not been hit yet! - I am slightly puzzled by a comment that one of our RYA instructors made recently to me about navigation though (in light of this post ) he said that it is possible to navigate sandbanks at night using only your radar and no charts - he has done it many times - yet - to date I have not seen any radar reflectors sticking out on the mud! is he talking Bo*&x? /forums/images/graemlins/confused.gif
Robin
Well-Known Member
Re: Stealth mode
I think we were on 1.5ml range and it was on our old boat with a 24ml radar and a big CRT screen, much better than our current LCD toy. The thing was that had we seen the idiot at 1.5mls we would have had some options, but at 0.75ml when he was seen and a closing speed of say 29kts we didn't have too many! We wanted to turn to port for Poole but rules said go to starboard which if I guessed correctly was where said prat would be if he had his WPT set on North Head and would turn to his port for Hurst! I just decided that the N Head buoy was the safest place so we pretty well stopped just a few yards from it.
I think we were on 1.5ml range and it was on our old boat with a 24ml radar and a big CRT screen, much better than our current LCD toy. The thing was that had we seen the idiot at 1.5mls we would have had some options, but at 0.75ml when he was seen and a closing speed of say 29kts we didn't have too many! We wanted to turn to port for Poole but rules said go to starboard which if I guessed correctly was where said prat would be if he had his WPT set on North Head and would turn to his port for Hurst! I just decided that the N Head buoy was the safest place so we pretty well stopped just a few yards from it.
clivew05
Well-Known Member
Re: Stealth mode
Sounds like a good call .... if this guy was doing 25knts in the FOG with no RADAR and no Reflector - I guess that there was not much chance of him obeying or even knowing the col regs .. even had he seen you!
Sounds like a good call .... if this guy was doing 25knts in the FOG with no RADAR and no Reflector - I guess that there was not much chance of him obeying or even knowing the col regs .. even had he seen you!