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Old 24-09-2012, 22:35   #361
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Dockhead has it spot on! In open waters minimum CPA's should be reckoned in miles. The ships I have sailed on had a minimum CPA of 2 miles written in the standing orders....less than a mile is considered a close call. On smaller workboats that we typically deliver, I still like to keep a 1-2 mile CPA. Tracking begins as soon as a target comes up on radar, usually 24 miles out and any course changes are planned out and executed 6-10 miles out. It takes a very attentive watchstander to pick up a sailboat out of the clutter on a lumpy day at 6 miles out on radar...visually, their lights are visible from about 2 miles or less Pogiving you very little time to determine their course and if there is risk of collision. A valid radar plot takes 6 minutes, and will not be right if either vessel changes course during that time. If I detect your presence at only 1mile and am doing 12kts and you are coming at me doing6kts....well you do the math. Not much time to sort things out. AIS helps immensely making up for the lack of visibility of small vessels in less than ideal conditions so close quarters situations can be comfortably avoided.
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Old 24-09-2012, 23:02   #362
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Re: Freighters vs. sailboats

I was chatting with a guy on another forum. He mentioned that he used RADAR to help him figure CPA to determine risk of collision.

Although it is GREAT to use all the neat-o- electronic whizmos, there is a really simple tool to use. Your eyes.

Coming from the 'Merchant Mariner' POV Some yacht crew have a really hard time distinguishing whether risk of collision exists. Some of you will grumble, yeah, don't patronize me, I know what I'm doing. That may be true. If so, then teach, talk about and share this info.

Sailboaters generally have a unique ability to judge set and drift. Much more so than powerboaters or (gasp) merchant mariners. Each and every time we get into a sailboat and sail we deal with side slip and set. I used to work at a yacht yard as a young guy. I know the amount of damage that occurs to yachts each season. I made pretty damn good money fixing some pretty spectacular crunches. Almost all the damages were done either to powerboats, or to sailboats under power. Most sailboats don't have collisions underway while sailing. Why?

Because sailboaters 'get' set and drift.


'Set and drift' is simply the sidewards movement in relation to your forward movement. We all have to deal with it, as we are close hauled, and the amazing thing (to me) is most other boaters don't 'get' it.

The issue with determining risk of collision is you have to use the ability to determine your set and drift in relation to the other guy. People look out on the horizon and see a lowly tugboat (me!) I am pointed in a direction. You look at me and think, I am setting this way, the tug is going that way, I should be clear of him. You hop down below, letting your youngster take the helm. After you make your sandwich, and clean up the mayo jar you dropped! you pop your head up and see my Tugboat 2 miles away. How the heck did I get so close?

If your boat has RADAR it has THE most important item in it to use to determine risk of collision. But, you have to know how to use it. And how to interpret its data.

This magic device is the EBL. Electronic Bearing Line. It used to be the old plastic bezel mounted tab on the top of the old CRT RADAR displays. It used to be that only commercial, large bulky sets had them.

Now we ALL have them! Ain't electronics grand!? The EBL is used to keep track of targets far away. The only caveat in use, you have to keep the same heading when you set the EBL, and when you read the EBL in a few minutes. Using the earlier example of a ship out at 12 miles, if you put it on the ship and read it in 3, 6 and 9 minutes (all while maintaining the same heading) If the oncoming ship is still on the EBL (and getting closer, bigger) it is going to hit you. If it is moving above the upper part of the line, the ship is going to pass ahead of you. If it is dropping below the EBL the ship is going to go astern of you.

It is that simple. Using the RADAR to 'watch' for you will tell you if you are the ships' next victim, or if you can go back to fishing.

The amazing thing is these RADARs have another function called "Trails." You can turn on the trails to mimic the effects of the EBL. One downside, if you have a lot of targets it can get VERY cluttered on the screen quickly. Another down side, is you have to know if your RADAR both has the ability to be displayed with either True or Relative trails. This ability to determine risk of collision ONLY works with the RADAR in Relative trails

The best thing to know, You don't need a RADAR, or Hand Bearing Compass to find this information out.

We all have the EBL's right in our own eyes! They don't cost a thing. And with a little practice you can simply look at another vessel and determine if they are a collision risk with NO other devices.

Sitting in your cockpit, you can tell just by 'frequent systematic observation' (that is the official description) whether you are going to have a collision with someone else.

Assuming you are steering a pretty constant course, keep your body in the same relative position. either sitting at the tiller, or sitting next to a winch. look at the oncoming vessel. Compare and line up the vessel with one or two items on your boat, a stanchion, a sheet block, a shroud. If you look around, you will find something to line up on, and be able to sit and observe the oncoming traffic. This only takes about 3 minutes of observing to determine if a risk exists. You don't even have to stay staring at the oncoming vessel. as long as you can put your head back in the same relative position, and line up the same fixed object you first lined up on, you can tell.

If the vessel is staying ON the same line, risk exists, if the vessel is moving forward, it will pass in front of you, if it is falling aft, it will pass aft of you. the only difference is if this is a large vessel that is close to you, it requires you to use either the bow, or the stern, depending on which way it is falling off the line of sight.

If you take a second to think about it, using your eyes, and something fixed on your boat is accomplishing the same thing as using your RADAR or HBC to determine if risk of collision exists.
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Old 24-09-2012, 23:20   #363
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Re: Freighters vs. sailboats

Maybe my radar set is not as good as others (and it's being replaced this winter), but I have not found the EBL to be as useful as other means to determine a collision risk. Theoretically, all you have to do is put the EBL on your target and watch whether it marches down the line towards you, but in practice when we are under sail our heading is not constant.

Maybe others have different experiences, but for me the gold standard of collision risk assessment is the HBC, which does not calculate a relative bearing but an absolute one, so even if your heading is wiggling around, the HBC is always telling you the real relative motion between you and the ship. It's pretty much idiot proof. Plus your looking with your own eyes at a real ship rather than having your head down in a video screen, so much better for 'situational awareness'.

I've been advised several times just to use my own eyes. I have to confess, I can't tell $h*t about a collision risk with my bare eyes at 5 or 6 miles out. I can't judge range at all because I have no idea whether I'm looking at a 300' or a 600' vessel, from that distance. Using a stanchion as a transit I can get a vague idea, but a 'vague idea' of a collision risk might in fact be a CPA of 2 miles, so useless information, and maybe a dangerous distraction, if there are multiple targets.

For all those reasons, I always have the HBC around my neck in the cockpit, and always have a spare on board.
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Old 25-09-2012, 02:22   #364
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Re: Freighters vs. sailboats

Quote:
Originally Posted by Dockhead View Post
Maybe my radar set is not as good as others (and it's being replaced this winter), but I have not found the EBL to be as useful as other means to determine a collision risk. Theoretically, all you have to do is put the EBL on your target and watch whether it marches down the line towards you, but in practice when we are under sail our heading is not constant.

Agree, the non stabilised, 8 inch display radar I have is inadequate to make a proper assessment of a risk of collision. Typically the heading may be swinging through 10 degree's. If target trails are in use, the display soon becomes a mess.
The radar's we use at work are something else, 24 inch display, gyro stabilised, a very different situation.
Using a yachts radar normally requires someone down below to observe the display, if your single handed, then your not at the place you should be.

In addition to the bearing compass, have some means to record the bearings, if you are observing two or more approaching vessels, you dont want to be forgetting what the last bearing was.
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Old 25-09-2012, 04:47   #365
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Re: Freighters vs. sailboats

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Agree, the non stabilised, 8 inch display radar I have is inadequate to make a proper assessment of a risk of collision. Typically the heading may be swinging through 10 degree's. If target trails are in use, the display soon becomes a mess.
The radar's we use at work are something else, 24 inch display, gyro stabilised, a very different situation.
Using a yachts radar normally requires someone down below to observe the display, if your single handed, then your not at the place you should be.

In addition to the bearing compass, have some means to record the bearings, if you are observing two or more approaching vessels, you dont want to be forgetting what the last bearing was.

Absolutely right, the posters that keep preaching about determining collision are missing the point. Determining collision is easy, Its what to do next with a ship at flank speed bearing down on you, or more importantly several.

The " just avoid them " brigade is fine TO A POINT, sometime you cant easily do that, hence we have to develop strategies to handle large differences in respective speed. A slow bulk carrier, at 10 knots is a much much easier issue to deal with then a big fast cat approaching at 30knots. In this case . YOU NEED TO BE SEEN. If not you dead. Hence AIS, prayers,, everything, you are a hedgehog on a motorway.

All these professional mariners, telling you to abide by rules, talk to them on VHF, yeah maybe thats fine in good old USA, but try this

Me: " Large freight vessel at xxxx:yyyyy", " This is the sailing vessel xxxxxx , bearing xxx from you at 2,5 miles"

repeat several time

Them :" Helloooo, who this, where are you , do you mean me"

I repeat my bearing for them , ie if they'd just look out the window

Me:" xxxx, what are you intentions"

Them " We go Denia, we no see you on radar , where you"

At this point I give up and try and avoid him

Its important to realize that many many commercial vessels are far from "gold" standard or have anyone on the bridge that understands or speaks English. Yes occasionally I get a remnant of good ol Blightys merchant marine, Ill get clipped accurate responses, radar info, weather ,etc, Ive had them use their long range radar to tell me what to expect hours away etc. great stuff and take a bow bridge crew. BUT, it aint common.

So please commercial mariners, lay off telling me about proper COLREGS lights and so on and so forth , we aint the problem


Dave
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Old 25-09-2012, 05:09   #366
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Re: Freighters vs. sailboats

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Originally Posted by nigel1 View Post
In addition to the bearing compass, have some means to record the bearings, if you are observing two or more approaching vessels, you dont want to be forgetting what the last bearing was.
Steno pad and waterproof pencil always in my pocket; HBC around my neck. You are truly road kill in the English Channel without them.

If I have enough people on board, I have a separate port and starboard lookout, too.

By next season, however, I will have an expensive gyro-stabilized electronic compass and a new radar set. And transmitting AIS. I think tactics will change after that.
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Old 25-09-2012, 05:44   #367
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Re: Freighters vs. sailboats

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Originally Posted by goboatingnow View Post
Absolutely right, the posters that keep preaching about determining collision are missing the point. Determining collision is easy, Its what to do next with a ship at flank speed bearing down on you, or more importantly several.


So please commercial mariners, lay off telling me about proper COLREGS lights and so on and so forth , we aint the problem
Dave
There is a defect in your statement.

I disagree that determining risk is easy. For a guy who spends a couple weeks a year, TOTAL aboard, and does this in broad daylight, under excellent weather, this is easy. Now hone your skills, and use them at night, in inclement weather. YOU may be proficient. But there are others who don't even understand the subject!

Colregs apply to all of us. Colregs depends upon ALL of us doing several things. When the rate of closure is higher we must be able to make these decisions faster, and with less input. Have you actually checked your NAV lights for conformity to standards? Even factory installed lights sometimes DON'T meet the guidelines in Colregs annex. How about when heeled over? NO one ever checks these things! I talk to guys about this and am met with 'deer in the headlights' to borrow a phrase from another post.

So, while this post 'may' not apply to you, your community as a whole is deficient. I am not trying to make money off this, I have no ulterior motive here. I am just trying to inform others of a lack of conformity amongst a LARGE number of Yachters. The other issue of erratic behavior, as was posted on the colregs quiz post is emblematic. Even guys on this forum can't agree what should be done during a 10 knot (or less) incident. Then we have guys on this forum giving cease and desist demands concerning potential 30 knot encounters.
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Old 25-09-2012, 06:30   #368
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Re: Freighters vs. sailboats

Here is an edited repost of my reply to one of the members here who brought this subject up over on gCaptain where I have been a member for a while.

One issue that I have not really seen addressed is that while you (WAFI) and many members of the Cruisersforum may be very well educated on the COLREGS, little Betty Bareboat and her ilk often times have no real clue, and tend to act in random and unpredictable ways. If I am steaming and see a sailboat with a zero CPA, I can assume several things;

A. That guy knows the rules backwards and forwards, and is standing on, so I shall alter my course to pass clear.
B. That guy may know the rules, but may be inexperienced and interpret my maneuver incorrectly and do some random (edited) at the last minute to put himself in danger of collision.
C. That idiot has no friggin clue and is just obliviously meandering along and will do the stupidest and most dangerous possible thing once he comes up from grabbing a beer and notices that I am close to him.

Experience has inevitably led me towards always assuming choice C. Most professional Captains I know tend to think in terms of worst case scenario. Unfortunately when dealing with interactions between ships and yachts all it takes is one incorrectly handled scenario to ruin someones's career or end someone's life.
I spent a long time running research vessels which conducted manned submersible launch/recovery operations, and was at most other times in some RAM (restricted in ability to maneuver) configuration while working. I would frequently be told, after finally raising someone on the radio to request a specific CPA that "I'm a sailing vessel, and I have the RIGHT-OF-WAY!" or in certain areas of the world (S. Florida, New England, Caribbean) when I would issue a securite' call that I was recovering a manned submersible and request a 2 mile CPA from all vessels in the area. It was like ringing a dinner bell and every moron from miles around would get as close as they possibly could for the best view, snapping photos and shooting video like Cletus-the-slack-jawed-yokel as I repeatedly sounded 5 short blasts on the ship's whistle. Sometimes this earned return random honking, sometimes applause. Never the desired response of getting away from over the top of my submarine or out from under my bow or off my recovery path.

I have done a sailing circumnavigation (sans electronics in the 1970's) and have met many excellent and expert mariners on sailboats, but when operating a ship I sadly have to make assumptions about the lowest common denominator. (I am a 7th issue USCG Licensed Master Oceans)

My biggest piece of advice, get an AIS, and when in congested/restricted areas, just stay the heck out of the way.

Final thought, when I am sailing (a sailboat) I NEVER, EVER cling to "Stand on Vessel" status. I will maneuver to avoid close quarter situations early and obviously irrespective of what the COLREGS state. Small plastic boat vs. large steel ship. I know who wins every time, and there are some real idiots on the bridges of large commercial vessels as well, I'm not going to give them the chance to sink me if I can help it. By all means call me on the radio if you are in any doubt about what I am doing or what you are doing, just don't call "UmmmmYeah... That big ship... ummmm,.... do you see me?" " Yeahhhh,....Ummmm, I'm the Swan with the puce' bootstriping and the kevlar sails on the port tack" Another reason to get an AIS, I will always answer to my vessel name.

Cheers,
Mike
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Old 25-09-2012, 06:40   #369
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Re: Freighters vs. sailboats

Hello Mike,

The main point of this discussion is so that little Betty Bareboat may get to have an understanding of the Colregs, or at least may be tempted to pick up a copy and read them.
Like you, I hold a Masters Foreign Going ticket, but also spend a lot of my leave sailing
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Old 25-09-2012, 07:00   #370
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Re: Freighters vs. sailboats

Understood Nigel, and I get that the participants hare are all actively trying to be part of the solution. Unfortunately there is no AIS for level of knowledge/professionalism, in the cockpit or on the bridge.
So from the big, fast, steel-ship perspective, unless I have spoken to someone on the radio, I have no way of knowing what kind of sailor I am dealing with. Another facet to this issue which I saw raised earlier in the thread, I may have already made passing arrangements with 1 or 2 or 5 other large ships which are over the horizon or out of RADAR range from a small sailboat well before I even pick you up visually or on RADAR. This happens often in busy places like the Straights of FL, approaches to chokepoints like Gibraltar and entrances to major shipping ports. This may severely limit my options in what actions I can take to avoid a close quarters situation with you. If you are the "Stand on" vessel and I can not for some reason take early and obvious action to avoid you I am sure as hell going to try to get you on the radio. Also, I will almost NEVER go left. (Unless I absolutely have to)
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Old 25-09-2012, 07:04   #371
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Re: Freighters vs. sailboats

It would appear that the defensive posture exhibited by some, and their vociferous objection to ANY broach of the topic simply scares off the 'Betty Bareboat' that may benefit from this discourse. THAT is too bad.

Although the statistics may not indicate, most of the forum members are 'wanna be' lifetime ocean voyagers. When in reality they are simply looking for info on how to jump into the world of cruising. Isn't it in YOUR best collective interest to let as many people know about the issues that may have an affect on saving your/their life? This thread is 25 pages long, approaching 400 posts. It is a topic of HUGE importance to all of us. But usually (and this is whole crux of the problem) People don't come to read this forum until they have had a close encounter that they are mystified about how, and why it happened.

Part of NOT getting ran over by a merchant vessel is a two part equation.

The first part is knowing whether or not you are going to be hit.
The second part is realizing it is in both your interests to avoid collision. Remember a merchant vessel is only about 35 meters wide. That is not so hard to make sure you are not in front of a 35 meter wide vessel.

Placing blame is like a kids game. Avoid the incident in the first place. When you are driving down the road and a lorry pulls out in front of you do you keep your speed and heading? Of course not. You pull aside, slow down, speed up. Do whatever is necessary to avoid collision. The same applies at sea. Generally we pull to the right. Sometimes we slow or stop. Sometimes we both turn and slow or stop. Sometimes, if there is enough distance we simply turn early to avoid creating an incident in the first place.

As a personal aside to Goboatingnow: I too thought I knew everything once. Now I am sure I don't. But after a 32 year career at sea, I am pretty confident of how to do it safely, without incident and efficiently. But, above ALL I know that I always have something to learn, or to share with others to teach. "It" is rarely the other guys fault.
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Old 25-09-2012, 07:20   #372
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Re: Freighters vs. sailboats

A note on using a Non-Stabilized RADAR display (in "heads-up" mode) to determine risk of collision or CPA. If your display is away from the wheel, and you have two people, one on helm, and one on RADAR, you can set your EBL while at a specific compass heading.
"Honey when you are steady on 270 yell "MARK!"." and then repeat the process 3 and/or 6 minutes later, and so on as long as the average or aggregate heading is relatively steady, this will give you a good idea of the change in relative bearing and allow an estimate of CPA.
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Old 25-09-2012, 07:31   #373
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Re: Freighters vs. sailboats

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A note on using a Non-Stabilized RADAR display (in "heads-up" mode) to determine risk of collision or CPA. If your display is away from the wheel, and you have two people, one on helm, and one on RADAR, you can set your EBL while at a specific compass heading.
"Honey when you are steady on 270 yell "MARK!"." and then repeat the process 3 and/or 6 minutes later, and so on as long as the average or aggregate heading is relatively steady, this will give you a good idea of the change in relative bearing and allow an estimate of CPA.

This is how it was done for years before any of us had stabilized displays. Even using the heading of the vessel, with the fleegles (tell tales) on the jib set correctly, (unless the wind is veering or backing wildly) you can call 'Marks' on them also. It does not matter where you get your heading from, as long as it is from the same source a few minutes later.
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Old 25-09-2012, 07:33   #374
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Re: Freighters vs. sailboats

Here is a quick analysis of nearly 400 posts that Betty Bareboat can take away and digest.

About half the experienced yachties will stand on as required by the CRs and the other half won't, they prefer just to stay well out of the way.

Some of the experienced commercial skippers want the yachties to follow the CRs and some just want them to stay well out of the way.

I reckon that Betty will say WTF, if these guys can't agree, why bother with something so complex as the CRs, it probably won't happen to me and off she will sail, leaving as much confusion in her wake as this thread generates.

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Old 25-09-2012, 07:43   #375
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Re: Freighters vs. sailboats

+1
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