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Old 17-08-2015, 07:26   #61
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Re: Autopilot does not equal Stand On Vessel!

Maybe the Coast Guard should give a Colregs test oevery known mariner and if they flunk banish them from the ocean!! LOL! Then those of us that remained would not have to worry because we may never see any other boats!😂😂😂
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Old 17-08-2015, 09:28   #62
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Re: Autopilot does not equal Stand On Vessel!

There is a general confusion in the US as to the definition of "commercial fishing" versus "recreational fishing" as C has referenced/pointed out. Here in the Great Lakes, most fishermen are "recreational" fishermen, by definition, even though they have paying customers aboard. However, most of them believe they have the right of way when they have lines in the water. Yesterday, we were 15 miles offshore in Lake Michigan in 280-300 feet of water and were on a collision course with a recreational fisherman. We were the only two boats within eyesight of each other. We were the stand on vessel and as we approached, I believed he was not going to alter course. He was running downriggers and yellowbirds. He had several opportunities to alter course as we approached but held his course. We were on autopilot. As we neared the vessel, I saw one of his customers was fighting a fish. Should I have held my course since I was the "stand on" vessel? Although I was legally in the right, commonsense and courtesy dictated a course change. He landed his fish and we nudged happily upwind to our old course heading after passing them. The point is that courtesy is lacking today on the water. And, for a prudent person to believe that any vessel operator knows the rules of the road is foolish and dangerous. My personal opinion is that we always avoid these situations since it causes less stress and provides the safest course from point A to B. And, if you try to educate them via radio, I believe their animosity and rudeness will only become worse. Remember the old folk saying: Never try to teach a pig to sing . . . it is a waste of time . . . and annoys the pig. Good luck and good sailing.
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Old 17-08-2015, 09:38   #63
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Re: Autopilot does not equal Stand On Vessel!

Yesterday, on the water coming back to Anacortes, motoring in no wind back to the marina. There is a notorious chokepoint at Cap Sante point where boats coming and going from the east side marinas (hundreds of boats and the Customs docks) have to go around. You also go by the scenic port with lots of boat building going on, etc. So people keep close to shore and cut the corner. All sizes of boats, from huge oil tankers going to/from the refineries there, plus tugs, 120' recreational yachts, and small 15' outboard dories. You have to be especially careful there needless to say.

You have to try and figure out not only boats closing on you towards you but keep a good lookout behind. Well, this 40' power boat comes up from behind us. We are going 7kts and they must have been going 7.5kts so they are slowly gaining on us. However, we are close to shore and a big ship and they are closer. Our course takes us even closer to shore and it should have been very obvious to the other boat so I am surprised they maintained course. And then two boats come around the corner headed directly for us, one who will have to come between the other power boat that is now next to us and one on the outside limiting my options.

I had already decided I wasn't going to enforce my right of way as the overtaken boat since clearly the other boat did not have a clue. It was good that I beared off. Turns out the skipper was being given instructions by the gentlemen on the flybridge. The skipper was obviously a novice and looked to be the owner's granddaughter and he was explaining to her how to drive the boat. Not a good lesson. Not on autopilot per se but in essence it was.

On the way out earlier in the day, we did play dodge'em with a big powerboat coming in while we went out. He was hell bent on maintaining his course despite our being in the way, and going about 20kts I judged. I changed course to make it obvious which side we should pass but he clearly thought I should have made a 90 degree turn to starboard so he would not have to change. Another kind of "autopilot".

But the real danger of autopilots is off the Washington coast - about 10 miles off. It is a heavily crabbed area so hundreds and hundreds of crab pot floats are bobbing everywhere for hundreds of miles. A no fish zone of about 1 mile width has been established that goes north south about 10 miles offshore. There are nav books that give gps waypoints to transit this narrow "highway" so that boats going north south can have some hope of missing the crab pots at night and bad weather when you can't see them. They are hard to see even when the water is calm in daylight too. So this is a good thing.

But boats load in the exact same waypoints in to their autopilots. So you are guaranteed to be on the exact same course, or reciprocal course, with all the other boats using that channel. It is one of the most hazardous passages anywhere. And in the deeper water areas, trawlers literally "farm" areas back and forth with nets for bottom fish. They will go 5 miles then turn about and go over and do another 5 mile run the opposite direction. They are always on autopilot and often as not no one is at the helm as they need all hands to man the deck fishing. You have to play dodge'em out there too.

I much rather be a hundred miles offshore.
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Old 17-08-2015, 11:34   #64
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Re: Autopilot does not equal Stand On Vessel!

Quote:
Originally Posted by colemj View Post

. ... I'm flabbergasted that when a situation is described as purposefully setting a waypoint on a known charted buoy (or land) and going below while underway, then hitting the buoy/land - there are people here who jump up and say the problem is with an integrated AP.

No, it's not.

Mark
Totally agree Mark....that is a whole new level of dumb!
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Old 17-08-2015, 13:32   #65
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Re: Autopilot does not equal Stand On Vessel!

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No, the problem isn't linking the AP to the GPS - the problem is setting waypoints on the markers themselves.

Who in their right mind would set a waypoint to a known charted hard bit? I'm astounded to hear that people actually do this. I never considered doing this before and am quite taken aback that others have.

Anyone setting an AP on a compass course (no integration to the GPS) to take them directly to a waypoint set on a known charted hard bit also has this potential for disaster and is saved only by any providential current or leeway.

Of course, they then run up on rocks that were not on their planned direct route...

I don't buy the explanation that ONLY those with integrated AP/GPS are using the exact same waypoints, while those purists with standalone AP's are not.

Mark
Of course the problem isn't the simple fact that GPS and AP are linked. Thought that was a given. My mistake. Indeed the problems arise from how they are used. My point was that the problem is made worse because of how easy it is to go from exact point to exact point. Like any tool, when used incorrectly, bad things happen. I find in today's world, it takes less skill to do something when we can just download an app or buy a gizmo to fill in the gaps in our skill level. Which is what the AP and GPS linked do quite well. Hell, I even hear folks talk about not ever needing paper charts any more.
Yes Mark, the problem is how those gizmos are used.
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Old 17-08-2015, 15:35   #66
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Re: Autopilot does not equal Stand On Vessel!

Quote:
Originally Posted by Pelagic View Post
I have always refused to integrate my AP with GPS.

While attracted to the efficiency of it.. I felt it more important to assess the watchkeeper's diligence in minimizing the cross track error which I could monitor remotely

I thus found it a good measure of their lookout standards.

Also it taught and engaged the watchkeeper in assessing changing currents and leeway thus giving them a better feel of the vessel's true course in varying conditions.

This manual correction of AP has also helped me to identify a worsening steering or compass failure that would never have been noticed otherwise until complete failure.

Basically.....
You have to do something to stay alert, so why not manually adjust the AP to keep on track?
Brilliant solution dealing with multiple problems.





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Old 17-08-2015, 15:50   #67
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Re: Autopilot does not equal Stand On Vessel!

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Originally Posted by colemj View Post
That is all fine and good, but my point was that an AP integrated with a GPS is not the root cause of any of the problems discussed here. It isn't even a secondary cause.



It is simply an unexamined demon in some people's minds. I'm flabbergasted that when a situation is described as purposefully setting a waypoint on a known charted buoy (or land) and going below while underway, then hitting the buoy/land - there are people here who jump up and say the problem is with an integrated AP.



No, it's not.

Lack of adequate competent lookout is THE primary problem.

But integrated AP and GPS is at least a secondary reason if not a less important primary reason. With integration everyone transiting between two points follows the same line thru space with no cross-track error, the includes folks going in the reciprocal direction. Without integration the AP will maintain a heading rather than a course and wind and/or waves will push the vessel off the rhumb line providing better clearance to all others transiting that route.


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Old 17-08-2015, 16:10   #68
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Re: Autopilot does not equal Stand On Vessel!

Quote:
Originally Posted by Adelie View Post
But integrated AP and GPS is at least a secondary reason if not a less important primary reason. With integration everyone transiting between two points follows the same line thru space with no cross-track error, the includes folks going in the reciprocal direction. Without integration the AP will maintain a heading rather than a course and wind and/or waves will push the vessel off the rhumb line providing better clearance to all others transiting that route.
If those two points of transit are set at buoys or similar, then the problem is still stupidity, not integration of the AP - competent lookout or not.

If those two points are randomly set somewhere sufficiently off of a buoy, then there would be no difference in probability of two boats coming to the same point guided by GPS or by compass. One might make the case that guided by compass presents enough error that it would INCREASE the probability of two boats colliding while steering toward random waypoints near a buoy.

Then what about our autopilot, which has a "no-drift" mode, where it follows a compass course but compensates for current and leeway - no integration to a GPS necessary?

How about two vessels on reciprocal courses experiencing the same current? Wouldn't they end up in the same trouble as two vessels with GPS-integrated AP's?

No, integrated AP's aren't even the secondary reason for any of this.

BTW, if the primary reason is no one on deck keeping watch, why is there even a discussion around secondary reasons?

Doctor: he died because he lit a stick of dynamite in his mouth while showing off drunk. Wife: what was the secondary reason for him dying? Was it the joint he was smoking at the time?

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Old 17-08-2015, 16:40   #69
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Re: Autopilot does not equal Stand On Vessel!

I think we need to ask ourselves this Question:

What is the Primary purpose of using an Autopilot?

1....To maintain a more effective course than can be done by hand.

2.... To relieve the watchkeeper from the drudgery of manual steering.

3.... To assure that desired waypoint will be reached in the shortest time

4.... To free up the watchkeeper from manual steering so that he can maintain a more effective watch of all boat components
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Old 17-08-2015, 16:43   #70
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Re: Autopilot does not equal Stand On Vessel!

Pel, you forgot reason 5. To free up the wheelsman so he can go chip/paint/shovel iron ore/chip ice.

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Old 17-08-2015, 18:05   #71
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Re: Autopilot does not equal Stand On Vessel!

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Originally Posted by Pelagic View Post
I think we need to ask ourselves this Question:

What is the Primary purpose of using an Autopilot?

1....To maintain a more effective course than can be done by hand.

2.... To relieve the watchkeeper from the drudgery of manual steering.

3.... To assure that desired waypoint will be reached in the shortest time

4.... To free up the watchkeeper from manual steering so that he can maintain a more effective watch of all boat components
If these are ranked in importance, then I would rank the above 4-2-1-3 in descending importance.

BTW, I just finished integrating our autopilot with our TV. Now when I tune to Fox News, it turns right; MSNBC it turns left; any program showing GOP debates or Israeli or Greek politics and it goes backwards.

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Old 17-08-2015, 18:35   #72
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Re: Autopilot does not equal Stand On Vessel!

Quote:
Originally Posted by colemj View Post
If those two points of transit are set at buoys or similar, then the problem is still stupidity, not integration of the AP - competent lookout or not.
If there was no integration the negative effects of that stupidity would be greatly reduced.


If those two points are randomly set somewhere sufficiently off of a buoy, then there would be no difference in probability of two boats coming to the same point guided by GPS or by compass.
In the case of 2 GPS boats there is no possibility of collision as long as the courses don't cross and they are further apart than the allowable cross sum of the allowable cross-track errors for the 2 units involved. If one or both boats use compass only autopilots the odds of collision will depend on cross currents, leeway, and how often the crew is checking the cross-track error on the GPS and changing the course steered on the autopilot.

One might make the case that guided by compass presents enough error that it would INCREASE the probability of two boats colliding while steering toward random waypoints near a buoy.
Please explain how.

Then what about our autopilot, which has a "no-drift" mode, where it follows a compass course but compensates for current and leeway - no integration to a GPS necessary?
The "no-drift" mode for your auto pilot is an internal GPS that picks an arbitrary point at some large distance from your current position on the heading you set or are pointing at when your activate that mode and then sends internal steering commands to minimize cross-track error to that arbitrary point. It's a very cheap implementation with minimal memory requirements since there are only points to track, no graphical output and direct outputs to the autopilot. Lets say you point the boat towards your destination and get it aimed within 0.5* for a 10nm run. At 10nm you are going to be 530' off of target but still on the line to the arbitrary point the autopilot picked. At 1nm you are 53' off the point to point line and somebody coming the other way or overtaking that is following the line will miss you by 53' minus half of your beam and half of his beam.

How about two vessels on reciprocal courses experiencing the same current? Wouldn't they end up in the same trouble as two vessels with GPS-integrated AP's?
They could still collide but the odds are much lower. The odds of experiencing exactly the same net cross track error at the exact instant the pass are much reduced.

No, integrated AP's aren't even the secondary reason for any of this.
I disagree.

BTW, if the primary reason is no one on deck keeping watch, why is there even a discussion around secondary reasons?
Because if there was an autopilot with no integration the crew would have to periodically come up reset the autopilot for the new correct heading to destination, thus at least an occasional watch would be kept instead of none at all.

I'm not saying don't integrate the two, I'm saying integration contributes to the problem and changes to the integration may be part of the solution.
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Old 17-08-2015, 19:02   #73
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Re: Autopilot does not equal Stand On Vessel!

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Because if there was an autopilot with no integration the crew would have to periodically come up reset the autopilot for the new correct heading to destination, thus at least an occasional watch would be kept instead of none at all.

I'm not saying don't integrate the two, I'm saying integration contributes to the problem and changes to the integration may be part of the solution.


I agree.
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Old 17-08-2015, 19:14   #74
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Re: Autopilot does not equal Stand On Vessel!

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Originally Posted by Adelie View Post
Because if there was an autopilot with no integration the crew would have to periodically come up reset the autopilot for the new correct heading to destination, thus at least an occasional watch would be kept instead of none at all.
This is the same hypothetical crew that charted waypoints on a known, fixed buoy and then went below for the duration of the trip? You think somehow they would develop far better seamanship, navigation skills and responsibility just by not having their AP integrated with their GPS? Pulling that cable is all that stands between numbnuts and geniuses?

You will need to explain how we have our AP integrated to our GPS and do not succumb to this known trap.

Again, how does a "secondary cause" even get into this conversation, or earns any importance? "Yes, he died while hand-feeding a grizzly bear, BUT the place he got those twinkies was open for business, so that was the secondary cause"...

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Old 17-08-2015, 19:17   #75
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Re: Autopilot does not equal Stand On Vessel!

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I agree.
You agree that the crew who charted waypoints on known fixed buoys and went below would have come up and regularly adjusted their AP course if only it wasn't integrated with the GPS?

It amazes me the lengths people will stretch to make a situation fit their notions…

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