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Old 10-07-2013, 06:37   #721
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Re: Freighters vs. Sailboats

There has been a lot of nit picking over the exact terminology of ColRegs on this thread. More like a discussion between lawyers!! So far as I can recall there has been little/no mention of the one of the least expensive, most useful tools for avoiding close call with freighters. For just a few hundred bucks a receive only AIS will show you where the freighter is, its course, closest distance if both courses are maintained. We have done many overnights in busy shipping locations. The AIS is the best tool available for understanding the locations of multiple targets, especially in the dark, fog, or poor visibility conditions. We also use with radar ARPA but AIS is invaluable. I recall one dark night off of Savannah when we had at least 15 ships on AIS. It made the situation infinitely easier to deal with and I did not even try to take measurements with my hand held compass!! Lastly, my personal philosophy is to keep as far away as possible from large ships, though we did have a run-in with a USN warship that kept threatening "live fire exercises" in the Bahamas and it kept getting closer and closer, all the while telling us to move out of range. It was very hard to get out of its way at 7kt!!
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Old 10-07-2013, 06:54   #722
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Re: Freighters vs. Sailboats

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Originally Posted by chrisjs View Post
There has been a lot of nit picking over the exact terminology of ColRegs on this thread. More like a discussion between lawyers!! So far as I can recall there has been little/no mention of the one of the least expensive, most useful tools for avoiding close call with freighters. For just a few hundred bucks a receive only AIS will show you where the freighter is, its course, closest distance if both courses are maintained. We have done many overnights in busy shipping locations. The AIS is the best tool available for understanding the locations of multiple targets, especially in the dark, fog, or poor visibility conditions. We also use with radar ARPA but AIS is invaluable. I recall one dark night off of Savannah when we had at least 15 ships on AIS. It made the situation infinitely easier to deal with and I did not even try to take measurements with my hand held compass!! Lastly, my personal philosophy is to keep as far away as possible from large ships, though we did have a run-in with a USN warship that kept threatening "live fire exercises" in the Bahamas and it kept getting closer and closer, all the while telling us to move out of range. It was very hard to get out of its way at 7kt!!

Well, they had a little fun with you, didn't you ... or they were COMPLETELY ignorant about sailboats -- oh wait, I've met more than one ex-Navy like that.

If I were going to be sailing in this area at night I would most definitely look into AIS (don't know enough to say I would buy it) ...

but will shrimp fleets show up on it? Of course, they're lit up like Christmas trees, but there's always fog ...
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Old 10-07-2013, 10:24   #723
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Re: Freighters vs. Sailboats

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How did you end up in such a predicament -- did you fall asleep at the helm? You should be able to see a freighter in plenty of time to plan to sail behind it. It's not like they're hard to see.
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Where should the sailboat turn? To point at the bow of the ship? No. You will only hasten the collision. Ideally you point in a right angle away. But for all practical purposes you point to go BEHIND the ship. He concept of pointing at the stern is to be done when you are off to the side before you have waited SO long that you are dead ahead of the bow of a ship.
If your sailboat is going 4 or 5 kts and the freighter is going better than 20 kts, and if a risk of collision exists, you will be fine on his bow - this is a mathematical certainty. And just think about this for a moment - if he is maintaining a steady bearing as you judge it - by compass bearing or lining it up with a stanchion, then you are on a steady bearing on his bridge. That is to say you will be fine on his bow when he first appears on the horizon.

It doesn't matter how far away he is, if you point at him (and in this case pointing at his stern is pointing at him) then you will not be doing much to avoid that risk of collision.

Of course you could turn tail and run off on a course that's perpendicular to and away from his heading - that will ensure a wide passing distance, but I have to wonder if you'll ever make it to your destination if you keep turning away every time you see a ship on the horizon?

Personally I'd rather follow the colregs and continue towards my destination.
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Old 10-07-2013, 10:42   #724
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Re: Freighters vs. Sailboats

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If your sailboat is going 4 or 5 kts and the freighter is going better than 20 kts, and if a risk of collision exists, you will be fine on his bow - this is a mathematical certainty. And just think about this for a moment - if he is maintaining a steady bearing as you judge it - by compass bearing or lining it up with a stanchion, then you are on a steady bearing on his bridge. That is to say you will be fine on his bow when he first appears on the horizon.

It doesn't matter how far away he is, if you point at him (and in this case pointing at his stern is pointing at him) then you will not be doing much to avoid that risk of collision.

Of course you could turn tail and run off on a course that's perpendicular to and away from his heading - that will ensure a wide passing distance, but I have to wonder if you'll ever make it to your destination if you keep turning away every time you see a ship on the horizon?

Personally I'd rather follow the colregs and continue towards my destination.

Of course.

Two FREIGHTERS would have to make serious judgments about where they were in relation to each other.
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Old 10-07-2013, 11:42   #725
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Re: Freighters vs. Sailboats

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Why?

Because they do NOT understand Relative Motion.........



The bottom line is: Learn how relative motion is affecting your perceptions of what it REALLY happening out there..........


Explaining how to sight on someone (however done, HBC, Binocs, etc) is useless if the person does not grasp the concept of Relative motion........


Some people don't grasp 'set' some don't get Leeway. Some have a hard time 'seeing' what is happening. THIS is the issue.

No rules, No blame, just NO education! There's always something else to learn aboard. Relative motion is one of them. Learn it before it kills you!
Well put.

I would like to add though that even with education some (many I think) simply cannot learn it. You can try to educate but alas, there will not be a true (worthwhile) grasp of the necessary skill.

Two examples I know of.

1. Some people can learn to do math in their head. Some cannot. Education efforts fail. We don't really know why but some just can't "get it". This would be me.

2. Some people can't "think in 3D and can't learn it. Example is trying to insert a spinal needle in the correct "spot" to administer the med. Once the needle has entered the skin they cannot see in their "minds eye" the relationship between their hand/needle and the unseen anatomy that is out of sight. They struggle. And fail too.

Some just aren't going to ever "get it".
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Old 10-07-2013, 12:33   #726
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Re: Freighters vs. Sailboats

I am truly amazed at how many interpretations of ColRegs can fit on the head of a pin! Even with changes in wording to facilitate clarity, one thing I always remember from my mariner schooling back in the 50's was 'tonnage rules'.
Anyone who has stood on the bridge of a VLCC, a container ship or aircraft carrier (Tiger cruise from Hawaii to San Diego) knows that visibility dead ahead and even 10 degrees off the bow is about zero out about a mile or two. In other words, unless watchkeeping aboard the larger vessel is good (aboard naval vessels it is great and redundant), you've got a big blind spot on the big guy if you are a little guy. Couple this with a relatively high speed and low maneuverability, best give the big guys lots of room even if it means you have to stay out over night and not make port. Dealing with towing situations, lower speeds but even less maneuverability, particularly in inland waterways where channel restrictions reduce turning/directional options even more.
Common sense and avoiding collision situations is everyones' responsibility. Someone noted that in a collision at sea (which can ruin your whole day!), each party has a portion of responsibility... just a question of how much.
There are many commenting on this thread who are very experienced, knowledgeable and clear in their explainations. There are others who, when I read between the lines, are very knowledgeable, well read and well versed in the published regulations but may lack the experience of navigating in heavy traffic through a convergence zone like off LA or San Francisco. Both make a valuable contribution but I'd rather sail with experience given the choice. Great debate, however... Phil
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Old 10-07-2013, 12:42   #727
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Re: Freighters vs. Sailboats

@Lodesman: You are incorrect in your assessment about the vectors involved. Of course you could meet any vessel dead on the bow. To state that in any collision you will 'definitely' meet at the bow of a ship is in error. To state that in any collision you will start fine on the bow is wrong also. One post about 20 ago posted a photo of a close ship on the beam. How did that happen? You say that any collision will occur when the ship is sighted and it will be sighted on the bow. I am having trouble figuring this one out. Any instance of collision can happen from from broad off either bow, and impact can be anywhere from the bow to the stern. Give me some time, and I will make a visual demonstration on a RADAR Rapid Radar Plotting sheet. What you are insisting as absolute is only representative, NOT all encompassing.
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Old 10-07-2013, 13:05   #728
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Re: Freighters vs. Sailboats

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@Lodesman: You are incorrect in your assessment about the vectors involved. Of course you could meet any vessel dead on the bow. To state that in any collision you will 'definitely' meet at the bow of a ship is in error. To state that in any collision you will start fine on the bow is wrong also. One post about 20 ago posted a photo of a close ship on the beam. How did that happen? You say that any collision will occur when the ship is sighted and it will be sighted on the bow. I am having trouble figuring this one out. Any instance of collision can happen from from broad off either bow, and impact can be anywhere from the bow to the stern. Give me some time, and I will make a visual demonstration on a RADAR Rapid Radar Plotting sheet. What you are insisting as absolute is only representative, NOT all encompassing.

This poor horse is dead, he's been dead, the wake is over, all the cows and chickens and sheep have moved on to eat grass and bugs and grass, and we're still trying to take the poor thing for a ride!

No post will be all encompassing, but I still maintain that it doesn't require special equipment unless you're another freighter, because then you can both move at the same speed. but I judge all the time whethe or not I'm on a collision course with another sailboat, or skidoo, or power boat, all the time. If I pulled out a handlheld compass all the time, that's all I'd do on some days. Freighters are easy by comparison because they're much more predictable, and much bigger, much easier to gauge. I'm sure some of you *enjoy* using your HHC in that way, but that doesn't make it necessary.

i'm still trying to figure out how avoiding a freighter would force me to anchor out overnight. I don't get that. They move so fast, they're out of your way in no time. Maybe there are ports where freighters and pleasure craft have to compete for the same space? Not here, and not with the Government Cut in Miami -- pleasure craft aren't allowed to use it -- at least that's what they told us at Dinner Key Marina. We didn't stop to check on line - we just said "OK!"
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Old 10-07-2013, 13:37   #729
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Re: Freighters vs. Sailboats

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Originally Posted by Lodesman View Post
If your sailboat is going 4 or 5 kts and the freighter is going better than 20 kts, and if a risk of collision exists, you will be fine on his bow - this is a mathematical certainty. And just think about this for a moment - if he is maintaining a steady bearing as you judge it - by compass bearing or lining it up with a stanchion, then you are on a steady bearing on his bridge. That is to say you will be fine on his bow when he first appears on the horizon.

It doesn't matter how far away he is, if you point at him (and in this case pointing at his stern is pointing at him) then you will not be doing much to avoid that risk of collision.

Of course you could turn tail and run off on a course that's perpendicular to and away from his heading - that will ensure a wide passing distance, but I have to wonder if you'll ever make it to your destination if you keep turning away every time you see a ship on the horizon?

Personally I'd rather follow the colregs and continue towards my destination.
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Originally Posted by cappy208 View Post
@Lodesman: You are incorrect in your assessment about the vectors involved. Of course you could meet any vessel dead on the bow. To state that in any collision you will 'definitely' meet at the bow of a ship is in error. To state that in any collision you will start fine on the bow is wrong also. One post about 20 ago posted a photo of a close ship on the beam. How did that happen? You say that any collision will occur when the ship is sighted and it will be sighted on the bow. I am having trouble figuring this one out. Any instance of collision can happen from from broad off either bow, and impact can be anywhere from the bow to the stern. Give me some time, and I will make a visual demonstration on a RADAR Rapid Radar Plotting sheet. What you are insisting as absolute is only representative, NOT all encompassing.
Lodesman's first paragraph is actually correct. He stated if your speed is 5 knots and the approaching boat is 20+ knots, you will be fine on his bow (not that he will be fine on your bow).

At speeds of 5 and 20 knots you will be less than 14 degrees off his bow if you are going to collide. I would call this 'fine' . And yes, this is a mathematical certainty.

Nowhere does Lodesman state where the impact will occur. I think you are misreading what he has written.

I do, however, disagree with Lodesman's second paragraph.

And I definitely disagree with his last sentence. If you follow ColRegs and you are the stand off boat, by the time you spot him and determine that a collision is likely, evasive action must almost immediately be taken to avoid a collision (and we all at least agree ColRegs state this must be done ).

It is late here, but I will post diagrams tomorrow.

PS Edited to add: Evasive action must almost immediately be taken if you want to stay with a nm of him. You could delay it a little, but not by much if you were willing to pass closer.
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Old 10-07-2013, 13:49   #730
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Re: Freighters vs. Sailboats

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Originally Posted by cappy208 View Post
@Lodesman: You are incorrect in your assessment about the vectors involved. Of course you could meet any vessel dead on the bow. To state that in any collision you will 'definitely' meet at the bow of a ship is in error. To state that in any collision you will start fine on the bow is wrong also.
It would be really nice if you could stop saying I'm incorrect, when time and again I prove otherwise. I wish you would also read what I write, rather than make up your own interpretation of what I write. I didn't say that any collision will meet at the bow - I said (and I'm sick of repeating this) that where a slow-moving boat has a risk of collision with a fast-moving ship, the boat will be fine on the ship's bow during the period that risk of collision exists.

Now take out a chart - a nice one with lots of open water.
Plot an 'X' on it - this will be the point of collision between two vessels in one hour; a collision occurs because two vessels try to occupy the same piece of water, at the same time.

Let's assume the sailboat is breezing along lazily, watching the dolphins, making 4 kts on a broad reach in a light breeze (this is a cruising forum after all). Set your compass to 4NM and centred on the X draw a circle. 1 hour prior to the collision, the sailboat will be on this circle - it doesn't really matter what his course is; he's steering towards the X, and he'll be there in one hour.

From the X draw a line 22NM in length in any direction. The freighter is at the end of the line, steering towards the collision point (X) at 22 kts - in one hour, he will be at the X.

Now measure the angle between the freighter and the X (the freighter's course), then measure the angle between the freighter and the outer limits of the sailboat's circle. That is the maximum angle the sailboat can be on the freighter's bow, for collision to happen. Regardless of the sailboat's course, he is somewhere within about 10 degrees of the freighter's bow.

I'm honestly not sure that I can explain it any simpler than that.
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Old 10-07-2013, 13:55   #731
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Meeting a single ship and " pointing at his stern " is fine advice , but crossing larger numbers of ships or having several performing overtaking , while at the same time others are doing a port to port passing maneouver , and you ate in the same sea room.

Now you have to apply the COLREGS , no " jinxing " for people's stern.

Look at more complex sceanarios not simple ones

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Old 10-07-2013, 13:58   #732
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Quote:
Originally Posted by Lodesman View Post

It would be really nice if you could stop saying I'm incorrect, when time and again I prove otherwise. I wish you would also read what I write, rather than make up your own interpretation of what I write. I didn't say that any collision will meet at the bow - I said (and I'm sick of repeating this) that where a slow-moving boat has a risk of collision with a fast-moving ship, the boat will be fine on the ship's bow during the period that risk of collision exists.

Now take out a chart - a nice one with lots of open water.
Plot an 'X' on it - this will be the point of collision between two vessels in one hour; a collision occurs because two vessels try to occupy the same piece of water, at the same time.

Let's assume the sailboat is breezing along lazily, watching the dolphins, making 4 kts on a broad reach in a light breeze (this is a cruising forum after all). Set your compass to 4NM and centred on the X draw a circle. 1 hour prior to the collision, the sailboat will be on this circle - it doesn't really matter what his course is; he's steering towards the X, and he'll be there in one hour.

From the X draw a line 22NM in length in any direction. The freighter is at the end of the line, steering towards the collision point (X) at 22 kts - in one hour, he will be at the X.

Now measure the angle between the freighter and the X (the freighter's course), then measure the angle between the freighter and the outer limits of the sailboat's circle. That is the maximum angle the sailboat can be on the freighter's bow, for collision to happen. Regardless of the sailboat's course, he is somewhere within about 10 degrees of the freighter's bow.

I'm honestly not sure that I can explain it any simpler than that.
Well this is self evident , you don't get run over by his stern !!

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Old 10-07-2013, 14:03   #733
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Re: Freighters vs. Sailboats

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It would be really nice if you could stop saying I'm incorrect, when time and again I prove otherwise. I wish you would also read what I write, rather than make up your own interpretation of what I write. I didn't say that any collision will meet at the bow - I said (and I'm sick of repeating this) that where a slow-moving boat has a risk of collision with a fast-moving ship, the boat will be fine on the ship's bow during the period that risk of collision exists.

Now take out a chart - a nice one with lots of open water.
Plot an 'X' on it - this will be the point of collision between two vessels in one hour; a collision occurs because two vessels try to occupy the same piece of water, at the same time.

Let's assume the sailboat is breezing along lazily, watching the dolphins, making 4 kts on a broad reach in a light breeze (this is a cruising forum after all). Set your compass to 4NM and centred on the X draw a circle. 1 hour prior to the collision, the sailboat will be on this circle - it doesn't really matter what his course is; he's steering towards the X, and he'll be there in one hour.

From the X draw a line 22NM in length in any direction. The freighter is at the end of the line, steering towards the collision point (X) at 22 kts - in one hour, he will be at the X.

Now measure the angle between the freighter and the X (the freighter's course), then measure the angle between the freighter and the outer limits of the sailboat's circle. That is the maximum angle the sailboat can be on the freighter's bow, for collision to happen. Regardless of the sailboat's course, he is somewhere within about 10 degrees of the freighter's bow.

I'm honestly not sure that I can explain it any simpler than that.

BUT IT'S ALL HYPOTHETICAL, assuming that a sailboat will be so busy watching dolphins that they don't see a FREIGHTER until the moment of collision. As I said before, I don't see how this could happen unless someone fell asleep at the helm. All you have to do is do a 180 and you're outta there. Or, if you really are about to hit bow to bow, 90 degrees. You get my point.

I never hear about freighter or cruise ship/sailboat collisions, not ever, even though lots and lots of boats cross the shipping channel every day.

Can someone provide evidence that this is anything but a very rare occurrence? Surely if all those people are incapable of judging whether they're going to collide with a freighter or not, those collisions have been in the news.
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Old 10-07-2013, 14:03   #734
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Re: Freighters vs. Sailboats

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......
Now measure the angle between the freighter and the X (the freighter's course), then measure the angle between the freighter and the outer limits of the sailboat's circle. That is the maximum angle the sailboat can be on the freighter's bow, for collision to happen. Regardless of the sailboat's course, he is somewhere within about 10 degrees of the freighter's bow.
I agree. Given constant speed and direction of the 2 boats, if your speed is 4 knots and the freighter's is 22 knots, you will be within 10 degrees off his bow (or elsewhere on his boat unless he is close) if you are to collide. 10.3 degrees to make it a little more accurate .

I think Cappy has just misinterpreted what you have written.
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Old 10-07-2013, 14:09   #735
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Re: Freighters vs. Sailboats

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I do, however, disagree with Lodesman's second paragraph.

And I definitely disagree with his last sentence. If you follow ColRegs and you are the stand off boat, by the time you spot him and determine that a collision is likely, evasive action must almost immediately be taken to avoid a collision (and we all at least agree ColRegs state this must be done ).
I appreciate the assist Lass. Perhaps you could explain how you disagree with the parts that you do. As to my 2nd para, I concede that if the sailboat was on a perpendicular course (ie. as far away from the freighter's path as is possible), and pointed at the freighter when the freighter was over the horizon at 20 odd miles, then the sailboat would avoid collision and have a nice safe passing, but in a more typical situation where the freighter is 5 or 6 miles away, and the sailboat is closer to the freighter's course or reciprocal, then I stand by my remarks.

I'm intrigued by your last statement, and await further explanation. I feel that a deep discussion on the requirements of the stand on vessel (rule 17) is forthcoming.
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