AIS Class A & B v Radar

Hi Talulah. I see I wrote the article in 2005. Here's an extract:
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Is radar only for use in restricted visibility?

Five COLREGs specifically refer to radar - 6(b), 7(b) (c), 8(b), and 19(d), some using the word ‘operational’ which many boaters interpret to mean ‘would work if it was turned on’.

I asked the Maritime and Coastguard Agency (MCA), the enforcement body for the COLREGs in the UK, whether the word ‘operational’ meant ‘a working set which must be turned on’ rather than ‘a working set if it happens to be turned on?’ The MCA’s Navigation Manager replied,

‘Of course, in the context of Rule 6, ‘operational’ means working and turned on and working, (otherwise one that was not turned on would be a major characteristic under 6(b)(i)).

‘If it is turned off, it might as well not exist and you cannot include the radar on board within consideration of safe speed in accordance with Rule 6. Additionally if you have radar in circumstances where it could be of value such as in restricted visibility and then decide not to turn it on or use it, you could be in violation of Rule 2 and/or Rule 5.’

In other words, always on.

Furthermore, case law shows that if your craft is fitted with a radar you must use it and by implication know how to use it to its full potential for the conditions you are experiencing.

Remember that radar is not only for looking ahead, it also sees what’s coming up behind...
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Whilst I have read what you said and the response you had in your discussions with the MCA I don't agee with the contents.
i.e If it is turned off, it might as well not exist.
Not so. A radar that is turned off may be turned on if it is approriate in the circumstances or conditions to do so.
This is where 5 comes in.

I would like to see the case law you are referring to.
Incidentally I would like to see why the wording for Rule 5 was changed.
Was it because of this ambiguity?
 
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Furthermore, case law shows that if your craft is fitted with a radar you must use it and by implication know how to use it to its full potential for the conditions you are experiencing.
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That really does not make much sense for the amateur boater, but for a commercial boat I'm sure it does. For example, if I buy a secondhand boat are you really saying I can't bring it back to my home port before learning how to competently use the radar? Even having had radar for years I would not say I was 100% competent in using it, although I have a pretty good idea how it should be used.

But back to the original question, for me it would definitely be radar and then AIS, but almost certainly both as AIS is so relatively inexpensive so almost a no brainer to fit at the same time.
 
I don't think there's anything afloat broadcasting an AIS signal that even the cheaper radar wouldn't spot, while obviously the opposite is not true.
Yes, checking the CPA with a touchscreen MFD is easy peasy, and sort of fun possibly.
Otoh, it does take some skills to tune and read e a radar properly, but if forced to choose, assuming that the helmsman actually CAN use a radar, that's a no brainer imho.
 
Five COLREGs specifically refer to radar - 6(b), 7(b) (c), 8(b), and 19(d), ...
I asked the Maritime and Coastguard Agency (MCA), ...

Piers, I'm firmly of the view that having a radar fitted but turned off in circumstances where it doesn't add anything useful to the situation (eg a sunny calm day ) is not an offence under Colregs, regardless of what the MCA people you asked might have said. As I've said before, Colregs is a poor piece of work imho by modern stnadards and should be re-written, but despite that I'm clear in my views on this specific point. On calm sunny days I often choose not to turn my radar on
 
So are life jackets ... 99% of the time ...
Not quite a fair quote..;)
AIS is so jam packed with leisure boats transmitting in the Solent, you are lucky if you can see the charting underneath...
Do racing yachts use it for racing- I never understood why so many transmit all the time?
 
Piers, I'm firmly of the view that having a radar fitted but turned off in circumstances where it doesn't add anything useful to the situation (eg a sunny calm day ) is not an offence under Colregs, regardless of what the MCA people you asked might have said.

The MCA didn't actually say what Piers seems to be claiming anyway. The quote includes the caveat "in circumstances where it could be of value such as in restricted visibility", implying that their view is the same as yours.

Pete
 
Hmm, yep. Piers, not wishing to pick a fight but I'm intrigued about your assertion "case law shows that if your craft is fitted with a radar you must use it". Can you cite that law? I really doubt there is any legal precedent saying the requirement for radar to be turned on is absolute, as opposed to only when conditions dictate
 
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Hmm, yep. Piers, not wishing to pick a fight but I'm intrigued about your assertion "if your craft is fitted with a radar you must use it". Can you cite that law? I really doubt there is any legal precedent saying the requirement for radar to be turned on is absolute, as opposed to only when conditions dictate

Hi John. I'm running around South Africa at the moment but will reply over the couple of days when I have a moment to check my references. If I write something for publication, I always ensure I quote rather than assume - for obvious reasons!
 
On calm sunny days I often choose not to turn my radar on
Same here, and fwiw I'm also unaware of a "legal" requirement to keep it on.
That said, if I'm on a passage (as opposed to coastal cruising), I leave it on regardless of how good the visibility is, because I find it useful for deciding well in advance whether to keep my course or take any action.
I understand that the AIS (which I don't have) is even better in this respect, but you can still come across other non-AIS transmitting vessels...
 
Same here, and fwiw I'm also unaware of a "legal" requirement to keep it on.
That said, if I'm on a passage (as opposed to coastal cruising), I leave it on regardless of how good the visibility is, because I find it useful for deciding well in advance whether to keep my course or take any action.
I understand that the AIS (which I don't have) is even better in this respect, but you can still come across other non-AIS transmitting vessels...
Yep to all that MM. Even in great weather I too use it on passage because it can see long distances so well. It's useful to know there is a ship crossing your track 12 miles in advance, but that sort of info is irrelevant if you are coastal cruising. AIS gives arguably better info, but potentially at less range: while I pick up a ship on AIS easily at 12nm, some boats with crummy aerials only become AIS visible at a mile or so, and of course plenty of things have no AIS transmitter. For all the reasons given above, AIS doesn't replace radar.
Anyway, the only point I'm keen to establish is that it is lawful to choose not to turn the radar on if the skipper reasonably decides it wouldn't provide any useful incremental information. That question is worth drilling into, a bit, imho
Perhaps a worthwhile retirement project would be to re-write Colregs :D:D

@Piers: no worries - enjoy SA!
 
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Perhaps a worthwhile retirement project would be to re-write Colregs :D:D
LOL, worthwhile it might well be, but I'd rather learn to varnish wood first, whenever I'll begin to be bored of swimming, snorkeling, posting on the forum, having fun with friends, and ...ermm... doing just about nothing else! :cool:

I'm also curious to hear about the lawful-ness of keeping the radar turned off, anyway.
 
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LOL, worthwhile it might well be, but I'd rather learn to varnish wood first, whenever I'll begin to be bored of swimming, snorkeling, posting on the forum, having fun with friends, and ...ermm... doing just about nothing else! :cool:

I'm also curious to hear about the lawful-ness of keeping the radar turned off, anyway.
Haha, yep, good point. I take the comment back, and yes to all the things in your list!:encouragement:
 
You want to try cruising in the Med
The radar has far less use than in UK waters.
Thats as may be but IMHO its still an essential tool and I'd have radar over AIS every time. With radar, you stand a chance of seeing everything you might hit but with AIS you will only see a few things you might hit. Even in the Med, I have the radar on all the time if I'm driving from downstairs and even if the weather is fine. It's an extra pair of eyes as far as I'm concerned
 
Anyway, the only point I'm keen to establish is that it is lawful to choose not to turn the radar on if the skipper reasonably decides it wouldn't provide any useful incremental information. That question is worth drilling into, a bit, imho

I guess Rule 5 is relevant here

Every vessel shall at all times maintain a proper look-out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions so as to make a full appraisal of the situation and of the risk of collision

and Rule 7 (b) certainly seems to oblige you to use your radar if a risk of collision exists

Proper use shall be made of radar equipment if fitted and operational, including long-range scanning to obtain early warning of risk of collision and radar plotting or equivalent systematic observation of detected objects.


In the event of a collision, I guess you'd have a big problem explaining in court why you weren't using your radar at the time, if it was fitted to your boat.
 
So what happens when the person twiddling the knobs has no idea what he is doing? Maybe fitted and operational but it also needs an operator. Further more if you were to miss something on radar would you be declared negligent? If you don't have it you can't be held negligent for missing something on it.
Does radar need maintenance/calibrating etc.?
 
AIS can sometimes provide a little bit of information overload...

TheSolentinCowesWeek.jpg


:D
 
So what happens when the person twiddling the knobs has no idea what he is doing? Maybe fitted and operational but it also needs an operator. Further more if you were to miss something on radar would you be declared negligent? If you don't have it you can't be held negligent for missing something on it.
Does radar need maintenance/calibrating etc.?

Mmm yes, I suppose if you take the steering wheel out of your car, you couldn't be prosecuted for dangerous driving if you hit somebody!

Joking apart, there was a well publicised collision a few years back between a ferry and a yacht south of the Isle of Wight. IIRC the MAIB investigation concluded that the officers of the watch on the ferry didn't pick up the yacht on the radar (although they may have glimpsed it by eye). Although manslaughter charges were brought, the officers were acquitted so to answer your question I do not believe that you would be declared negligent if you missed something on your radar although I guess your case would be strengthened if you could prove that you had adequate training in the use of it. The question really is this. If you've got a radar why wouldn't you be using it and if you've got a choice whether to buy one or not, why wouldn't you, knowing that it could help you avoid a collision and keep you and your family safer?

Although you can fiddle with radar settings, modern radars generally have auto tune, auto gain and maybe auto sea so they're almost plug and play but there's a high degree of interpretation required in understanding what it is you're seeing on the screen. That really comes with experience and its actually well worthwile using the radar in good viz so you can see what different objects look like on your radar screen

One of the most frightening experiences I have ever had on a boat was crossing the shipping lanes in the English Channel in thick fog on a boat without radar. We knew the big ships were out there, we could hear them and even catch a glimpse of them occasionally but we had no way of knowing if we were on a collision course to hit any of them. Speaking personally, I would never be without radar on a cruising boat
 
Mmm yes, I suppose if you take the steering wheel out of your car, you couldn't be prosecuted for dangerous driving if you hit somebody!

Joking apart, there was a well publicised collision a few years back between a ferry and a yacht south of the Isle of Wight. IIRC the MAIB investigation concluded that the officers of the watch on the ferry didn't pick up the yacht on the radar (although they may have glimpsed it by eye). Although manslaughter charges were brought, the officers were acquitted so to answer your question I do not believe that you would be declared negligent if you missed something on your radar although I guess your case would be strengthened if you could prove that you had adequate training in the use of it. The question really is this. If you've got a radar why wouldn't you be using it and if you've got a choice whether to buy one or not, why wouldn't you, knowing that it could help you avoid a collision and keep you and your family safer?

Although you can fiddle with radar settings, modern radars generally have auto tune, auto gain and maybe auto sea so they're almost plug and play but there's a high degree of interpretation required in understanding what it is you're seeing on the screen. That really comes with experience and its actually well worthwile using the radar in good viz so you can see what different objects look like on your radar screen

One of the most frightening experiences I have ever had on a boat was crossing the shipping lanes in the English Channel in thick fog on a boat without radar. We knew the big ships were out there, we could hear them and even catch a glimpse of them occasionally but we had no way of knowing if we were on a collision course to hit any of them. Speaking personally, I would never be without radar on a cruising boat

As mentioned. Digital radar really is realtime plug and play; the image of an operator with his face buried in a green screen twiddling gain, tune, sea-clutter and rain-clutter knobs is a thing of the past.
 
, knowing that it could help you avoid a collision and keep you and your family safer?
I agree what you say generally, but just to be clear, in discussing the legality of having a radar turned off I was talking only about the situations where I know it makes zero difference to safety, as was MapisM. For example, when you come out of the marina on a sunny calm day and go 5 miles along the coast to anchor in a bay to go swimming. I was debating merely the point of law, and I'm certainly not against using a radar in other situations when it is useful, or practising with it in perfect weather, and so on. I wouldn't spec a boat without one (and I'm contemplating fitting a second one, as part of my winter updates!)
 
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