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Old 21-01-2012, 08:19   #271
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Originally Posted by Shoalcove
Well, I don't mean to split hairs here but I never said the controller is respnsible for navigating the aircraft. I said that the controller is responsible to know where the plane is. In a non-radar environment that is accomplished by position reports and estimates for the next fix amongst other things. Again, I don't have the specific information at hand but as a controller I would be using that info to confirm separation and missing a report at an expected reporting point would be cause for concern.
As far as Enroute radar coverage goes, aircraft often fly below the coverage, particularly on departure and approach at smaller fields or in mountainous areas in Canada and I think you'll find the same situation in some areas of the USofA.
I really don't want this to drift into a discussion of ATC but merely wanted to agree with you that there was much more involved in the accident in Columbia than relying on electronic navigation aids.
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Yes. No need to argue and didnt mean to imply you took a position on controller responsibilities.

I guess this whole drift is my fault. I just saw a bunch of aviation references coming out and for some reason felt compelled to point out that aviation navigation is way more complex than the general impression here was letting on.
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Old 21-01-2012, 08:54   #272
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Re: Why Integrate the Autopilot ?

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Originally Posted by Ex-Calif View Post
... felt compelled to point out that aviation navigation is way more complex than the general impression here was letting on.
I could not agree more! The whole aviation world is incredibly complex and trying to simplify an accident to one root cause is wrongheaded. Studies I've seen suggest that there are usually many factors that compound to create an unsafe situation. That is the lesson we can take onto our boats.
It is rarely simply a case of being lulled by a chartplotter that gets us but rather the combination of being tired, seasick crew, bad wx, trying to meet a schedule and/or having out of date or insufficient info (like tide tables or paper charts for example) that add up to lead us down the path.
Thanks for sharing your thoughts on the matter, I always enjoy reading your posts.
Best regards.
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Old 21-01-2012, 10:38   #273
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Re: Why Integrate the Autopilot ?

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Originally Posted by goboatingnow View Post
Ill give a more reasoned approach as to why I never use wind vane mode. ( and before we start yes I know all about it and have tried it).

Firslty in a cruising boat who really cares about VMG. I care about a safe route first, then the route that makes the boat comfortable.Only then will I consider the most efficient direction

Secondly VMG is only useful where you are constrained by not being able to sail free. I try and avoid that and if is really bad, Ill probably motor. ( teh gentlemen doent sail to windward rule!)

Thirdly , if you sail by wind and dont set the alarms properly , you have have significant course shifts and for the complacent , that gets you into trouble, With bearing waypoint that I use, I will hear the sails stall , and I can retrim, but at least I dont deviate from my safe route inadvertently.

As a protection against gybing etc, that's a fallacy, most accidental gybes are caused by waves throwing the boat through the wind and because the boat is being sailed too deep for the circumstances.Autopilots no matter what mode will not save you

And finally , all wind steered autopilots I know have a wind shift course change limit error, when such an error occurs the autopilot drops out of control ( very very inconvient when youre in the head) The boat effectively is out of control at that point. AT least with track mode it takes a huge boat yaw to effect that.

From my sailing experience, wind shifts are slow gradual and anticipated, it some situation such as under thunderclouds I would consider wind directed steering as very very inappropriate.

Nop its not for me. ( and funnily I know very few, who use it).

Dave
As usual, I have to disagree with Dave. He really needs to sail more and expand his horizons beyond Raymarine autopilots. I let the autopilot sail in windpoint mode almost every time we need to go to weather, and have done that for more than 25,000 miles.

The surface wind fluctuates in strength and direction due to atmospheric convection. These convection cells are typically about 10-20 minutes in duration and can be observed even on cloudless days, and range from 5 degree and 3 knot changes to 50 degree and 30 knot changes depending on the vertical cloud development.

A look at your boat's polar diagram or a little sea time will teach you that boat speed is very sensitive to apparent wind angle when you are close-hauled WITHOUT THE ENGINE. If you insist on steering a compass course when the apparent wind angle goes from say 35 to 25 degrees, your boatspeed will drop by 25% or more. If the wind goes the other direction, from 35 to 45 degrees, you boat speed might pick up by only 5 to 10%.

All this means to the cruising sailor is that if you let the autopilot follow these constant wind shifts, you can sit back and enjoy a cool one as you pass all those catamarans and the silly buggers who have their autopilots on compass mode (or even worse, waypoint mode). Or you can take a nice nap at night instead of feeling the boat shake as the sails luff when your SO ignores the wind shifts.

The windshift alarm on my autopilot goes off when the wind shifts more than 15 degrees, which is a PITA on the open ocean. It has alarmed for days on end, but it NEVER STOPS STEERING THE BOAT. As far as safety is concerned I use the windpoint mode even more when I am beating in close waters--its improvement in efficiency saves tacks, and the autotack function puts you on the same angle on the other tack. The increase in VMG may make the difference in arriving before dark or not.

Note: I do not use the windpoint mode beyond about 120 degrees of apparent wind--I don't trust it not to gybe the boat.
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Old 21-01-2012, 11:05   #274
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Re: Why Integrate the Autopilot ?

Quote:
Originally Posted by Ex-Calif View Post
I guess this whole drift is my fault. I just saw a bunch of aviation references coming out and for some reason felt compelled to point out that aviation navigation is way more complex than the general impression here was letting on.
Quote:
Originally Posted by Shoalcove View Post
I could not agree more! The whole aviation world is incredibly complex and trying to simplify an accident to one root cause is wrongheaded. Studies I've seen suggest that there are usually many factors that compound to create an unsafe situation. That is the lesson we can take onto our boats.
It is rarely simply a case of being lulled by a chartplotter that gets us but rather the combination of being tired, seasick crew, bad wx, trying to meet a schedule and/or having out of date or insufficient info (like tide tables or paper charts for example) that add up to lead us down the path.
I believe the parallel to aviation mentioned in this thread isn't so much the likeness to navigation as it is the human trait of relying too much on the automation. Automation is great, but not infallible, as demonstrated in AF447.

(This may be dangerous in this crowd)
If you haven't read an account of what went on in the cockpit of AF447 take a read of:
Air France 447 Flight-Data Recorder Transcript - What Really Happened Aboard Air France 447 - Popular Mechanics
Assuming the writer didn't embellish too much, it's hard not to agree with his conclusions.

Understanding when it's time to take control away from the automation and operate the vessel by yourself vs trying to 'fix' the machine is, IMO, a fault in some humans. That aspect doesn't change, airplane or boat, although the outcome can be quite different.
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Old 22-01-2012, 04:49   #275
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Quote:
Originally Posted by DotDun

I believe the parallel to aviation mentioned in this thread isn't so much the likeness to navigation as it is the human trait of relying too much on the automation. Automation is great, but not infallible, as demonstrated in AF447.

(This may be dangerous in this crowd)
If you haven't read an account of what went on in the cockpit of AF447 take a read of:
Air France 447 Flight-Data Recorder Transcript - What Really Happened Aboard Air France 447 - Popular Mechanics
Assuming the writer didn't embellish too much, it's hard not to agree with his conclusions.

Understanding when it's time to take control away from the automation and operate the vessel by yourself vs trying to 'fix' the machine is, IMO, a fault in some humans. That aspect doesn't change, airplane or boat, although the outcome can be quite different.
The Air France comparison is the one that is least parallel to what we are talking about. As far as I know there is nothing to do with navigation related to the AF accident. Unless one considers all other commercial flights that night diverted around that area to avoid the storm cells.

The automation on the aircraft worked as it was supposed to and in fact the pilots were hand flying.

Unfortunately (my opinion) this appears to be pilot error. And not of situational awareness per se, but complete misunderstanding that the airplane was in a deep stall for which there is only one possible recovery - push the stick.
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Old 22-01-2012, 08:38   #276
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Re: Why Integrate the Autopilot ?

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Originally Posted by Ex-Calif View Post
The Air France comparison is the one that is least parallel to what we are talking about. As far as I know there is nothing to do with navigation related to the AF accident.
Correct. A pilot is there to perform three functions. In order of priority they are: to aviate. to navigate, and to communicate.

The AF incident was a failure to aviate. They did not recognize the airspeed indicator failure, reacted improperly and stalled the airplane, and then failed to recognize the aerodynamic stall, and failed to get the nose down to recover from it.
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Old 22-01-2012, 08:58   #277
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Re: Why Integrate the Autopilot ?

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Originally Posted by Ex-Calif View Post
The Air France comparison is the one that is least parallel to what we are talking about. As far as I know there is nothing to do with navigation related to the AF accident. Unless one considers all other commercial flights that night diverted around that area to avoid the storm cells.

The automation on the aircraft worked as it was supposed to and in fact the pilots were hand flying.

Unfortunately (my opinion) this appears to be pilot error. And not of situational awareness per se, but complete misunderstanding that the airplane was in a deep stall for which there is only one possible recovery - push the stick.
I brought aviation into this because -as stated earlier- the problem is most acute with the most immediate brutal negative outcome there, and is the most systematically studied.

The AF 447 crash is a case of the high degree of automation present inadvertently creating a threat nobody recognized.

That is, the high degree of automation was relied on to the point that basic flying skills had eroded dangerously on the line.

Air France recognizes it -now- and is doing something about it.

The Cali crash was emblematic of a culture problem as well (and not map shif really-will have to find a better example). As you may remember, 15 years ago was when the great migration from steam "gage" to glass cockpit was occurring. They lost SA because they focused on "the box".

American, like other carriers, was having some difficulty in making that transition.

Cali woke everybody up. In the aftermath, you now get the benefit of a worldwide GPWS, and at least in parts of the world where there are ICAO signators, a consistent WGS-84 nav data base.

I would equate the Concordia lying on her side, and the cruise ship industry's version of a "Cali moment".

"Automation addiction" has been an apparent problem in the commercial maritime world for some years now as well...

But it has not received the same level of systematic scrutiny the problem has in aviation. But many of the threat "threads" are the same.

Complacency, lack of training, poor systems engineering, and just a lack of understanding of how humans will naturally react to automated systems are no different.

You say you have been involved in an NTSB investigation. So have I. Its a real eye opening experience and changes your perspective in how you look at threat elements, wouldn't you agree?

Well, tying all this back to the boat world is this NTSB investigation:

Note this was from 16 years ago. Scroll down to page 34 and you will see the NTSB's determination is exactly what we are hashing about here now.

Innovations in technology have led to the use of advanced automated systems on modern maritime vessels. However, bridge automation has also changed the role of the watch officer on the ship. The watch officer, who previously was active in obtaining information about the environment and used this information for controlling the ship, is now “out of the control loop.”
The watch officer is relegated to passively monitoring the status and performance of the automated systems. As a result of passive monitoring, the crew members of the Royal Majesty missed numerous opportunities to recognize that the GPS was transmitting in DR mode and that the ship had deviated from its intended track.
Both the chief officer and the second officer exhibited decision making bias toward the automated map display. Based on information from the map display, the chief officer felt no need to visually verify his identification of the BA buoy.
The second officer was overly reliant on the map display when he failed to cross check the vessel’s position despite repeated indications of the Royal Majesty's deviation from its intended track. The Safety Board concludes that all the watchstanding officers were overly reliant on the automated position display of the NACOS 25 and were, for all intents and purposes, sailing the map display instead of using navigation aids or lookout information.

Bottom line from the NTSB:

All the watchstanding officers were overly reliant on the automated position display of the navigation and command system 25 and were, for all intents and purposes, sailing the map display instead of using navigation aids or lookout information.

The Sirens got em. And one need only look at the pics of the Concordia on her side, and the broken Rena on the reef half a world away to see the Sirens are still bagging the unaware at a sadly regular rate.

What does that mean to readers of cruiser forum? Walk into any West Marine and the first thing that stares you in the face are the said same sophisticated navigation systems giving you an alluring invitation to stop by.

If you invite them aboard, just make damned sure that you understand -AND REGULARLY EXERCISE- the basics of navigation.

Lest they lure you onto the rocks too.

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Old 22-01-2012, 10:04   #278
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Re: Why Integrate the Autopilot ?

Fixation on instruments is not limited to whether they are integrated or not IMHO. You can stare at the Radar or chartplotter and forget to look around regardless of how they interact. I would guess that there has been many cases where the same instrument suites have saved the day. In the aviation accident reports I've seen (and I've seen a few) there is never one factor in causing the event so it is important for us to be aware of how small issues can compound.
To me the discussion has moved into an opinion of what constitutes seamanship. I would like to hear more of the capabilities of the integrated AP and how others have set them up specifically since I'm about to install an AP this spring.
It does all make for fascinating reading!
Best regards.
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Old 22-01-2012, 10:23   #279
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Re: Why Integrate the Autopilot ?

Of course accidents always have multiple causes. What ties all these cases together is that automation of what had been a manual/cerebral action turned out to be a factor in each of them.

As these systems continue to migrate into pleasure boats we will be seeing the same negative human factors come to the fore. Indeed its already there.

So yes. This is about seamanship...just as were the tales of Homer.

Its about how you "integrate" modern electronics with the timeless principles of Prudent Seamanship.

And it ain't as easy as hitting the on button and cruising on your merry way.
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Old 22-01-2012, 10:27   #280
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Re: Why Integrate the Autopilot ?

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Originally Posted by sidmon View Post

What does that mean to readers of cruise forum? Walk into any West Marine and the first thing that stares you in the face are the said same sophisticated navigation systems giving you an alluring invitation to stop by.

If you invite them aboard, just make damned sure that you understand -AND REGULARLY EXERCISE- the basics of navigation.

Lest they lure you onto the rocks too.

Also correct.

I think that the greater hazard is having too little than too much when it comes to such nav equipment. In fact system redundancy should also be considered, as well as frequent cross checks to not rely on any single source.

We run in the fog occasionally. A GPS/chart-plotter coupled autopilot helps reduce the workload, and allows more attention to be devoted to the radar, and a close visual watch for logs, and traffic. Many recreational boaters get caught in the fog when not prepared for it. Small wood boats without radar reflectors are not easy to pick up on radar, and God knows how they get to where they are headed. We had two 35 foot power boats approach our port side while up on a plane despite our audible fog signal. One had a small radar, and it took an air horn to get their attention. They popped through the fog still on a plane and close to us. They heard the air horn and made 90 degree turns to get off their planes before reaching us.

I know that many here want to use the "keep it simple" approach. I just hope that those who do so recognize the limitations that go with it.
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Old 22-01-2012, 10:40   #281
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Re: Why Integrate the Autopilot ?

Interesting that the Costa Concordia incident is being presented as an example of loss of situational awareness / instrument fixation. As I read the details, it appears that the captain was on the bridge, driving the boat by looking out the window -- essentially by the seat of his pants.

As it turned out this was a spectacularly bad thing to do, but the incident was caused by *not* using the instruments (and apparently by a lack of common sense and appropriate caution.)

Or did I misinterpret what we know about the Concordia incident?
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Old 22-01-2012, 10:43   #282
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Re: Why Integrate the Autopilot ?

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Interesting that the Costa Concordia incident is being presented as an example of loss of situational awareness / instrument fixation. As I read the details, it appears that the captain was on the bridge, driving the boat by looking out the window -- essentially by the seat of his pants.

As it turned out this was a spectacularly bad thing to do, but the incident was caused by *not* using the instruments (and apparently by a lack of common sense and appropriate caution.)

Or did I misinterpret what we know about the Concordia incident?
You are absolutely correct, but there is a "complacency theory crowd" around that needs to blame modern technology and thus ignore these inconvenient facts

EDIT: They will tell you that the captain said that these rock were uncharted, which is their proof that it was integrated instrument complacency... it's probably the only statement of the captain that is believed by anyone

ciao!
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Old 22-01-2012, 10:45   #283
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Re: Why Integrate the Autopilot ?

I think you are correct Paul, from an interview of the captain.
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Old 22-01-2012, 10:54   #284
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Re: Why Integrate the Autopilot ?

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Originally Posted by Shoalcove View Post
To me the discussion has moved into an opinion of what constitutes seamanship. I would like to hear more of the capabilities of the integrated AP and how others have set them up specifically since I'm about to install an AP this spring.
It does all make for fascinating reading!
Best regards.

Integrate the AP, despite the fact I diont use the NAV/Track control, I find the windvane really useful, especially single handing.
If you dont integrate, you will mosy likely regret it later. Doing it at the same time as fitting the AP will not add much to the cost, doing it later will. You have the choice of which functions to use.
The one Mark described which can calculate tack and gype positions really does sound like the dogs danglies, I would like one.
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Old 22-01-2012, 10:55   #285
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Re: Why Integrate the Autopilot ?

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Interesting that the Costa Concordia incident is being presented as an example of loss of situational awareness / instrument fixation. As I read the details, it appears that the captain was on the bridge, driving the boat by looking out the window -- essentially by the seat of his pants.

As it turned out this was a spectacularly bad thing to do, but the incident was caused by *not* using the instruments (and apparently by a lack of common sense and appropriate caution.)

Or did I misinterpret what we know about the Concordia incident?
Schettino initially said that the rock he hit was not charted...

Here is a captain reared in the generation of high end nav suites and programmed courses. Not unlike the IRO and FO on AF 447, when he found himself outside the automated norm, he did not have the immediate awareness and sharpness of skill to cope.

What is inexcuseable in his case though is that he did it deliberately.

Hubris. Another timeless topic Homer waxed eloquent about, and a human trait that can get you into trouble in a hurry.
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