Over-Reliance on AIS -- Collision off Dungeness

[Polux]

Originally Posted by Muckle Flugga

... In the old days, a call of the likes of "Bulk carrier greater than 75 meters in length on course 045T, 5 nautical miles ESE of Knobby's Head" used to elicit few responses. Now when hailed with name, callsign and MMSI, I almost never fail to get a response.

Don't have AIS and hardly failed to get a response from ships. I call only when really it is necessary and if I can avoid them, or increase safety margins, with a slight change of course I do that even if I am the stand on vessel.

My concern is if I am being seen and sometimes I get some very laconic replies on a very poor and accented English, kind of "I see you" That's enough for me.

[Muckle Flugga]

Originally Posted by Dockhead

My success rate in hailing commercial vessels is not better than 50%, even calling by name and call sign.

My success rate in hailing commercial vessels by DSC is exactly 0%.

I don't even know how to be sure to get through -- maybe sat phone call?

Sorry to hear it. I would say that hailing by name and call sign mine is closer to 80% on average, but YMMV, and certainly in some waters it dives to 30% at best (South China to Banda seas etc.) I completely concur on the DSC front and rarely bother to try it anymore. At night I find a powerful searchlight helps!

[btrayfors]

Obviously, it depends on where you sail. But, in waters I know well (Maine to Caribbean) I've found it almost never necessary to try to call a ship.

1. You can see ships a long way away, even if they can't see you. There's generally plenty of time -- day or night -- to adjust your course & speed as necessary to stay way clear of them.

2. I prefer to spend my time and attention on deck tracking things with which I could conceivably collide, rather than wasting time gathering data from the AIS display, diverting my attention and trying to contact a ship.

In general, I've found the advice of an old San Francisco Bay pilot to be very wise: "Give way to tonnage"

And, I'd add, stay the f___ out of their way.

Bill

[Muckle Flugga]

Originally Posted by Polux

Don't have AIS and hardly failed to get a response from ships. I call only when really it is necessary and if I can avoid them, or increase safety margins, with a slight change of course I do that even if I am the stand on vessel.

My concern is if I am being seen and sometimes I get some very laconic replies on a very poor and accented English, kind of "I see you" That's enough for me.

Agreed for sure. Trying to tough it out as "stand on" vessel with a 100,000 ton vessel is kinda silly, if avoidance is simple. I once considered doing that very thing in the Norwegian sea when it was just little ol' me and the Queen Mary 2… but settled for informing them that according to their AIS they were "Anchored" at 19 knots

[Polux]

Originally Posted by Dockhead

My success rate in hailing commercial vessels is not better than 50%, even calling by name and call sign.

My success rate in hailing commercial vessels by DSC is exactly 0%.

I don't even know how to be sure to get through -- maybe sat phone call?

Maybe the way you call them? mine is simple, I all call when relatively close and when necessary. It is my wife that calls and that can have a positive effect (since I am outside steering the boat) and what we say is simple: Small sailboat ahead at (distance)... at your port side (or starboard) on possible collision course calling freighter at (position, if possible with landmark reference)...are you seeing me?

[conachair]

Originally Posted by HappyMdRSailor

I needed a new pair of shorts after viewing the AIS image Pete posted!

You'll never make a south coast fisherman

[Robin3]

Originally Posted by Muckle Flugga

Agreed for sure. Trying to tough it out as "stand on" vessel with a 100,000 ton vessel is kinda silly, if avoidance is simple. I once considered doing that very thing in the Norwegian sea when it was just little ol' me and the Queen Mary 2… but settled for informing them that according to their AIS they were "Anchored" at 19 knots

MAny years ago in the western Channel we 'overheard' a conversation between QE11 and a Royal Navy warship that started on 16 and switched to a working channel that happened to be the one used by Salcombe Harbour. IN one brief transmission Salcombe HM ( or a yoof in their launch/dory?) managed to tick off both the RN and QE11, telling them to get off ch... and go to a proper designated channel!

[Dockhead]

Originally Posted by Polux

Don't have AIS and hardly failed to get a response from ships. I call only when really it is necessary and if I can avoid them, or increase safety margins, with a slight change of course I do that even if I am the stand on vessel.

I don't really want to make this a COLREGS thread, but Polux, this is very bad anticollision practice. I cannot fail to speak up.

Don't change course AT ALL when you are the stand-on vessel, until you've given the other vessel a chance to maneuver. You are obligated to hold course and speed exactly so that he gets his chance to take the active role in the crossing. The whole science of collision avoidance doesn't work if you just jink around willy-nilly as you please, in a crossing with another vessel.

Once you do start maneuvering yourself (either before "risk of collision" exists, so probably at least 10 miles out) OR after you are permitted to start maneuvering as provided in the rules, THEN do not EVER make a "small change of course", but a dramatic one which will not be mistaken by the other vessel. This is specifically mentioned in the COLREGS, and is a serious and important point.

"Small changes of course" during a crossing with another vessel are very dangerous and are specifically prohibited by the COLREGS, because they can mess up the calculated CPA without, however, being noticeable to the other vessel. Especially bad is small, repeated changes of course (or speed) carried out by a skipper just eyeballing it, rather than plotting and working up a proper CPA. Lots of collisions happen because of this.

[Dockhead]

Originally Posted by conachair

You'll never make a south coast fisherman

Dover Straits passes 400 vessels a day, so one ship every 3 1/2 minutes, 24/7/365.

That doesn't count the cross-Channel traffic, which can also be quite heavy, and which includes a number of 45 knot fast cat ships.

Crossing the English Channel in a yacht is often compared to being a squirrel trying to run across the M25 motorway at rush hour. Without AIS, it is -- ahem -- really challenging. With AIS it is a lot easier because you get instant CPA calculations rather than having to do three or four plots at the same time.

[Dockhead]

Originally Posted by Polux

Maybe the way you call them? mine is simple, I all call when relatively close and when necessary. It is my wife that calls and that can have a positive effect (since I am outside steering the boat) and what we say is simple: Small sailboat ahead at (distance)... at your port side (or starboard) on possible collision course calling freighter at (position, if possible with landmark reference)...are you seeing me?

It's a function of where you are. In busy waters like where I sail these days, the bridges of ships are very busy and tend to simply ignore calls from WAFIs. In other waters, like the Mediterranean, or in U.S. waters, I have a much higher success rate.

[conachair]

Originally Posted by Dockhead

Dover Straits passes 400 vessels a day, so one ship every 3 1/2 minutes, 24/7/365.

That doesn't count the cross-Channel traffic, which can also be quite heavy, and which includes a number of 45 knot fast cat ships.

Crossing the English Channel in a yacht is often compared to being a squirrel trying to run across the M25 motorway at rush hour. Without AIS, it is -- ahem -- really challenging. With AIS it is a lot easier because you get instant CPA calculations rather than having to do three or four plots at the same time.

AIS is wonderful and I wouldn't like to be without it, but we still managed pretty much OK before crosschannel, getting close to the lanes you'll probably pass astern of the 4th ship you can see, hand bearing compass on that one.

it's just a lot easier now.

Driving the wrong way up a TSS in the middle of the night between tankers like that fishing boat in the image is a bit beyond my pay grade though....

[Muckle Flugga]

Originally Posted by Dockhead

Dover Straits passes 400 vessels a day, so one ship every 3 1/2 minutes, 24/7/365.

That doesn't count the cross-Channel traffic, which can also be quite heavy, and which includes a number of 45 knot fast cat ships.

Crossing the English Channel in a yacht is often compared to being a squirrel trying to run across the M25 motorway at rush hour. Without AIS, it is -- ahem -- really challenging. With AIS it is a lot easier because you get instant CPA calculations rather than having to do three or four plots at the same time.

Dover is definitely hectic. When passing through the straits in a N/S direction, I am often amazed at the fact that at any one time there may be more than one attempt to swim the straits. I mean, I understand back in the day when it was unique and all, but now? It just seems barmy. Each to their own I suppose but I have little doubt it annoys heck out of OOWs. Singapore straits is even more manic in my experience(see attached shots, in one you can see more than 200 targets in a 6 mile radius, about 40 of which were in the TSS zone), especially as it has 4 lanes of alternately opposing traffic. Did you manage to get out on the water when you were there recently?

[Dockhead]

Originally Posted by Muckle Flugga

Dover is definitely hectic. When passing through the straits in a N/S direction, I am often amazed at the fact that at any one time there may be more than one attempt to swim the straits. I mean, I understand back in the day when it was unique and all, but now? It just seems barmy. Each to their own I suppose but I have little doubt it annoys heck out of OOWs. Singapore straits is even more manic (see attached shots, in one you can see more than 200 targets in a 6 mile radius, about 40 of which were in the TSS zone). Did you manage to get out on the water when you were there recently?

I took everyone's advice and stayed shoreside. It was really interesting. The Straits are chock full of anchored vessels; I didn't see any huge volume of traffic underway, although maybe that was further off, out of sight.

Swimming the Dover Straits is pure madness. Bobbing around out there at 1 or 2 knots, totally invisible to traffic? I guess swimmer must have chase vessels with AIS and radios to try to warn off approaching ships? If I were the UK Home Secretary, I would forbid that practice.

[MarkJ]

Don't need to swim the Singapore straits... just walk on the polution!

[Muckle Flugga]

Originally Posted by Dockhead

I took everyone's advice and stayed shoreside. It was really interesting. The Straits are chock full of anchored vessels; I didn't see any huge volume of traffic underway, although maybe that was further off, out of sight.

Swimming the Dover Straits is pure madness. Bobbing around out there at 1 or 2 knots, totally invisible to traffic? I guess swimmer must have chase vessels with AIS and radios to try to warn off approaching ships? If I were the UK Home Secretary, I would forbid that practice.

Yep. Guard vessels. It is so common there is a small industry around it. And they broadcast their position on VHF annoyingly frequently, plus, if I remember right, transmit some kind of symbol on AIS. And yes.