Rule 17 -- Vid of a close encounter....

Just up the thread, someone kindly informed me that they are permanently fixed, and that running astern on one and ahead on the other can result in a capsize.
Ah, thanks. Apologies for not paying attention.

Fond memories of a trip to Lundy on Waverley. Would have been 1980 or ‘81, iirc - in company with my then 80 y/o grandmother, who scrambled up the hillside on the island like someone half her age.
 
Kingswear Castle? I think you'll find that she has a bow thruster. Beats me why they don't fit one to Waverley.
IIRC they considered fitting a bow thruster to the Waverley, but there is bugger all of her underwater there to fit one?

She does have a bow rudder too.
 
Sorry but you’re completely wrong. In my experience in open waters most ships will obey IRPCS. And also in my personal experience the bridge watchkeeping officers of ships would much rather yachts obeyed IRPCS too.

AIS is your friend. The only thing the large ship will probably not do is make large and substantial alterations of course or speed. It costs them money. They WILL tweak their course to open up the CPA.
Counter point - the ship that recently cut the class 40 in half.
 
Which is why you trust, but verify, using your own AIS, though TBH, AIS is a nuisance in the Solent and other crowded waters because, if you set it to give useful alarms mid-Channel, it'll be bleeping constantly.
Anyone relying on AIS inside the Solent to judge collision situations in good visibility is frankly dangerous.

The Class 40 in question did use their AIS, they identified a collision risk and called the ship, who confirmed that they would alter course. But then came back and said "you are dishonest, you're not a sailing boat, you take me for a piece of shit" and resumed his original course. By which time, doublehanded doing 18 knots with the kite up in fresh breeze it was too late for them to do anything.
What happened on the CIC Normandy Channel Race - Tip & Shaft
 
The Class 40 in question did use their AIS, they identified a collision risk and called the ship, who confirmed that they would alter course. But then came back and said "you are dishonest, you're not a sailing boat, you take me for a piece of shit" and resumed his original course. By which time, doublehanded doing 18 knots with the kite up in fresh breeze it was too late for them to do anything.
What happened on the CIC Normandy Channel Race - Tip & Shaft

That is a *way* better story than I expected when you first mentioned it!

‘You’re not a sailing boat, you take me for a piece of shit’ -- I'd say by any definition of the words in Rule 17 that releases them from any obligation to stand on. 😁

Am I misinterpreting or did the ship turn its AIS off?
 
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That is a *way* better story than I expected when you first mentioned it!

‘You’re not a sailing boat, you take me for a piece of shit’ -- I'd say by any definition of the words in Rule 17 that releases them from any obligation to stand on.

Am I misinterpreting or did the ship turn it's AIS off?
It turned it’s AIS off, and failed to respond to a Mayday.
 
I agree. It worries me hugely that there are people out their bobbing along with their only point of reference to the big outside world being a screen full of arrows and numbers. A bit of friendly advice. Head up, and on a swivel, eyes open and learn to judge whats going on in your immediate to medium distance environment. I think they used to call it seamanship.
 
I agree. It worries me hugely that there are people out their bobbing along with their only point of reference to the big outside world being a screen full of arrows and numbers. A bit of friendly advice. Head up, and on a swivel, eyes open and learn to judge whats going on in your immediate to medium distance environment. I think they used to call it seamanship.
My screen full of info is in the outside world. Where are your paper charts?
 

“Every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists. If there is any doubt such risk shall be deemed to exist.” Colregs, Rule 7


Therefore, monitoring AIS is one of the means to make that determination.

No idea why this is in bold, the editing options have disappeared
 

“Every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists. If there is any doubt such risk shall be deemed to exist.” Colregs, Rule 7


Therefore, monitoring AIS is one of the means to make that determination.

No idea why this is in bold, the editing options have disappeared
Of course it’s one of. But it’s also not obligatory equipment for all craft. We are obliged to use the old fashioned method of watching for the lack of a bearing change. Unless it’s foggy, when witchcraft and regular sound signals are the best that can be achieved.
 

“Every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists. If there is any doubt such risk shall be deemed to exist.” Colregs, Rule 7


Therefore, monitoring AIS is one of the means to make that determination.

No idea why this is in bold, the editing options have disappeared
Yes, it's also not appropriate inside the solent on a clear day. Principally because AIS CPA assumes that things will continue on their current course and speed, and even large ships do not really do that inside the solent. If you were just monitoring AIS CPA you could easily be taken off guard by the ship changing course to go south of Ryde middle for example.
 
… Principally because AIS CPA assumes that things will continue on their current course and speed, and even large ships do not really do that inside the solent. If you were just monitoring AIS CPA you could easily be taken off guard by the ship changing course to go south of Ryde middle for example.

Are you serious? AIS CPA constantly changes as vessels direction and speed change.

I understand that AIS clutter because of traffic density can make it inappropriate but the Solent is not always rammed.

Folks who are aware of the IRPCS understand Rule 7 which is implicit about all available means, where appropriate.
 
Are you serious? AIS CPA constantly changes as vessels direction and speed change.

I understand that AIS clutter because of traffic density can make it inappropriate but the Solent is not always rammed.

Folks who are aware of the IRPCS understand Rule 7 which is implicit about all available means, where appropriate.
It’s quite serious. In the ship channel in the Solent, you can do much better than AIS with the aid of a chart, or your knowledge of it, and some common sense. Otherwise you’d be edging round Egypt point in the back eddy, thinking you were about to be run down. You know where that ship is going, and when it’ll make the turn, within about 25 metres. We, and flaming, regularly race through and around the big ship channels and do not use AIS to work out collision likelihood.
 
@flaming said “ Principally because AIS CPA assumes that things will continue on their current course and speed,”

That is not true.

@Chiara’s slave I do understand your example but by applying Rule 7 you come to your conclusion.

The point is that AIS is expected to be used in line with Rule 7.
 
Are you serious? AIS CPA constantly changes as vessels direction and speed change.
Funnily enough I am perfectly well aware of how AIS works. And of course this is of exactly no use if your paths will intersect as the ship is making a turn, which they do a lot in the Solent. Since before it starts turning your AIS is telling you it will miss you comfortably, but if you left any avoiding action until your AIS was beeping at you as it kept turning towards you, it would be far too late.

Or if you're deciding in your small family cruiser if it's safe to cross from the western end of the Ryde middle bank towards Osbourne bay - and there is a ship heading East and just passing Prince consort. At that point in time your AIS would tell you he was heading North of Ryde middle, and that by continuing South you would be opening the CPA. Except we all know that large container ships and tankers normally pass South of Ryde middle, and he's just about to turn to Starboard to do that. And he'll be at the point you're crossing the main channel well before you've cleared the channel. Again, by the time your AIS has picked up on the potential issue it's way too late, your decision needed to be made well in advance of that.

Middle of the channel. Different matter entirely. But the fact that you are seriously arguing that AIS is the most appropriate collision avoidance tool in the Solent on a clear day.... That is terrifying.
 
The Egypt point example is a goid one because you could potentially be less than a minute away from a collision, according to AIS, yet be completely safe. I can’t offhand think of another quite such stark one, but there are other turns in the channel, plus of course you might be lee bowing in the deep water knowing perfectly well you’ll be on the other tack shortly.
 
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