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Old 22-01-2012, 13:02   #286
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Originally Posted by donradcliffe

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.
I don't know 28,000 miles approx, ( i stopped counting after that ) sailing since I was 17, have exposure to every electronic system there is and none too. I sailed oceans never used that " Wind vans " mode never needed it neither , damn new fangled stuff..

I would also rate the ray marine gyro autopilot as very good , and it does have a useful wind wave mode. In my opinion it's better then simrad ( though the output drivers are prone to failure) and certainly better then furuno, but hey after all that sailing what do I know. !!

Ps. I'd never have no electronics tell me when to tack. I decide that

Dave
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Old 22-01-2012, 13:11   #287
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Originally Posted by sidmon

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.
The captain has now testified that he was navigating the ship manually using sight. ( and claimed he was very familiar with the area ) he released his error when he saw the foam from the rocks. Had he in fact used his " integrated electronics " he would have clearly seen the size of his gamble. Of course maybe he's one of those that decide integrated electronics are the work of the devil.

The Concordia is an example of what happens when you don't use all the navigation inputs available and only rely on mark 1 eyeball.

In fact it was just someone you "chanced his arm " and lost , it had nothing to do with integrated bridges etc


In respect of AF 447 the failure was because two junior copilots ( the captain was resting) failed to actually read the outputs of their electronics and was not helped by the curious stall warning logic. They had alternative speed and in particularly altitude readings yet incorrect failed to spot high altitude stall, a problem exacerbated by not having such training.

There's Littleton either case, that is relevant to sailing. Firstly the control systems on a boat don't control it. Secondly everything happens much slower.
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Old 22-01-2012, 14:19   #288
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Re: Why Integrate the Autopilot ?

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Originally Posted by goboatingnow View Post
The captain has now testified that he was navigating the ship manually using sight. ( and claimed he was very familiar with the area ) he released his error when he saw the foam from the rocks. Had he in fact used his " integrated electronics " he would have clearly seen the size of his gamble. Of course maybe he's one of those that decide integrated electronics are the work of the devil.

The Concordia is an example of what happens when you don't use all the navigation inputs available and only rely on mark 1 eyeball.

In fact it was just someone you "chanced his arm " and lost , it had nothing to do with integrated bridges etc


In respect of AF 447 the failure was because two junior copilots ( the captain was resting) failed to actually read the outputs of their electronics and was not helped by the curious stall warning logic. They had alternative speed and in particularly altitude readings yet incorrect failed to spot high altitude stall, a problem exacerbated by not having such training.

There's Littleton either case, that is relevant to sailing. Firstly the control systems on a boat don't control it. Secondly everything happens much slower.
Dave

You dont get into a major airline seat unless you already have thousands of hours of flight experience already...And also a hefty percentage of that as PIC (pilot in command). There are some exceptions, but AF is not one of them.


Did you take the time to read any of the links provided?
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Old 22-01-2012, 14:43   #289
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Re: Why Integrate the Autopilot ?

Again, in spite of some who want to peg my position as either or when it comes to utilizing the latest in nav equipment, what ties the cases cited in the links above is the common elements of "automation addiction ".

In the case of Schettino, that fostered a dangerous sense of complacency and imprudence.

Its not an "either/or" in the use of the latest electronics. Alll I have been trying to point out is that there ARE human factors risks induced by their use.


And any Mariner that is prudent should be aware of them.
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Old 22-01-2012, 14:47   #290
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Re: Why Integrate the Autopilot ?

The report you provided also mentions flying through a thunder cell, icing, deficient pitot tube design, a junior pilot that just woke up, a disengaged autopilot, a unusual twin yoke design, and incorrect manual inputs to reverse a stall as contributing factors.
With all due respect, did you read them?
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Old 22-01-2012, 14:52   #291
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Re: Why Integrate the Autopilot ?

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Originally Posted by sidmon View Post
Again, in spite of some who want to peg my position as either or when it comes to utilizing the latest in nav equipment, what ties the cases cited in the links above is the common elements of "automation addiction ".

In the case of Schettino, that fostered a dangerous sense of complacency and imprudence.

Its not an "either/or" in the use of the latest electronics. Alll I have been trying to point out is that there ARE human factors risks induced by their use.


And any Mariner that is prudent should be aware of them.
So after all of this, you are trying to succinctly say the equivalent of "be careful or you will put an eye out".

Thank you.

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Old 22-01-2012, 15:26   #292
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Re: Why Integrate the Autopilot ?

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The report you provided also mentions flying through a thunder cell, icing, deficient pitot tube design, a junior pilot that just woke up, a disengaged autopilot, a unusual twin yoke design, and incorrect manual inputs to reverse a stall as contributing factors.
With all due respect, did you read them?

I work in the business of preventing...or breaking...such accident chains.
So I have not only read it but have implemented the lesssons learned.

Thats why I am bringing it up here. These systems are now finding their way into yet another unsuspecting venue.


As evidenced by the skepticism seen here, the learning curve will be needlessly painful.
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Old 22-01-2012, 15:32   #293
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Re: Why Integrate the Autopilot ?

Oh...might add that stalls and stall recoveries are some of the first maneuvers learned in pre solo training.

Its as basic as tacking and gybing....
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Old 22-01-2012, 15:35   #294
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Re: Why Integrate the Autopilot ?

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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.
"Integration" of an autopilot isn't really as involved or complicated as the term seems and has been taken to an extreme here.

An electronic autopilot, by definition, is already a highly integrated system in the sense that it takes heading data from a compass sensor, rudder feedback data from another sensor, puts it all together inside a computer that controls a power supply and mechanical or hydraulic drive mechanism and displays the data for you on a display/control unit. To get them to operate, most of them also require the purchaser to connect some type of speed sensor into them - either a GPS or a typical paddlewheel type transducer.

So the most basic below deck autopilot you can buy is already a system of 5 separate independent components integrated together with a communication network. And you have to connect at least one other, and preferably two, piece of equipment to it yourself.

Most people consider this collection of highly integrated gear as a "non-integrated" autopilot.

Where the line gets drawn between integrated and non-integrated is when one decides to connect either navigational waypoint data or wind data or both to the computer of the autopilot so that one could take advantage of two modes of operation not available to the basic integrated package. Namely, steer to waypoint and steer to wind angle. Or not take advantage of them - the choice does not go away once that communication cable is connected.

That's it. That is the whole scary big end of autopilot "integration" - waypoint and wind data.

If you have older instrumentation you want to integrate with a new autopilot, this can be more tricky of an installation because you will be dealing with NMEA0183 and its small little wires connected to terminal strips or through multiplexers. If you have NMEA2000 capable instruments and get the same in an autopilot, integration is dead simple - just plug the autopilot into the network backbone cable and you are finished. It will see all of the data on the network, it will share any data it generates (like its rate compass and rudder position data) and everything will interact with each other without the conflicts and finickiness of NMEA0183.

If you choose to operate this (now dangerous) integrated autopilot in one of its two modes not available to a non-integrated autopilot, you will interact with it in exactly the same way as if it wasn't integrated. The AP will not force you to go below and watch movies nor will it force you to stare at the chartplotter the entire time it is active. You may sit in your cockpit and keep a lookout. Go to the bathroom after scanning the horizon first, and everything else you would normally do if the autopilot was only steering to a heading.

If you put a waypoint on or through a piece of land, then you will learn a lesson and never make that mistake again - just like as if you gave it a heading that took it over the same. If you are steering along by a wind angle and sail into a waterspout or white squall where the wind suddenly veers dramatically, your wife and children will not be thrown overboard as the autopilot goes nuts and whips the boat around in a whirlpool frenzy. Instead it will simply beep annoyingly at you and hold its initial course.

The beeping will be annoying because you will have noticed the wind shift 1 second after it happens (if not have seen it coming first) and will be busy taking care of sails and other things that you will be free to handle. After which, you will then acknowledge the annoying beeping and the pilot will be happy. You will not be awakened from a drunken stupor with a lady of the night anymore than if the autopilot wasn't in wind mode.

And if you get one that can steer to VMG using polars and laylines, it will not force you to tack. You can still make that decision yourself - it simply tells you when the computations are such that it is most efficient. All of the high end pilots do this and all racing boats use them slavishly because they have learned that the amount of multi-modal data that can be integrated by a computer is far more up-to-date and precise than a busy human. But you can definitely call those shots yourself if you want.

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Old 22-01-2012, 15:39   #295
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Originally Posted by sidmon


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".

<snip>

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?
I am not sure I understand your point on Cali. Gpws is airplane based not ground based and has been available for 30(?) years. The cali flight was equiped with gpws.

In regards to investigations the number one rule is dont jump to conclusions. You have to be prepared to change your initial belief in the face of factual data.

I hope you dont take this wrong but your connections of cali and af to the cruise ship are way off base in regards to automation and navigation integration. All three may have a common factor of human error. For me it is too early to comment on the cruise ship.

The internet conjecturing may ultimately be right but for now it is bs. I know enough about investigations to know the real data will be released much later.
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Old 22-01-2012, 15:56   #296
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Re: Why Integrate the Autopilot ?

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I am not sure I understand your point on Cali. Gpws is airplane based not ground based and has been available for 30(?) years. The cali flight was equiped with gpws.

In regards to investigations the number one rule is dont jump to conclusions. You have to be prepared to change your initial belief in the face of factual data.

I hope you dont take this wrong but your connections of cali and af to the cruise ship are way off base in regards to automation and navigation integration. All three may have a common factor of human error. For me it is too early to comment on the cruise ship.

The internet conjecturing may ultimately be right but for now it is bs. I know enough about investigations to know the real data will be released much later.
Not sure what equipment you fly but the FMC databases now contain a comprehensive terrain database...that is a direct result of Cali.

Hope -you- dont take this wrong but the links I put up on p 19 are from peer reviwed cognitive engineering work. They are the ones making the aero and nautical connections.

As for the Concordia, you're right. All is speculation, but my bet still stands that his defense will hinge on the failure of all that expensive equipment on his bridge didn't warn him that he was standing into danger.


Lastly on the GPWS it was Cali and a couple of other CFIT accidents that raised the limitations of radar based Gpws. Hence the investment in the database.
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Old 22-01-2012, 15:58   #297
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Re: Why Integrate the Autopilot ?

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These systems are now finding their way into yet another unsuspecting venue.

As evidenced by the skepticism seen here, the learning curve will be needlessly painful.
I will be sure to resist integrating pitot tubes and twin yoke systems on my boat. Hopefully the icing is taken care of by my chosen latitudes.

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Old 22-01-2012, 16:17   #298
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Originally Posted by sidmon

You dont get into a major airline seat unless you already have thousands of hours of flight experience already...And also a hefty percentage of that as PIC (pilot in command). There are some exceptions, but AF is not one of them.

Did you take the time to read any of the links provided?
Yes all the reports including the third one. It notices the relief pilot and the copilot had not got high altitude stall training. Also the airbus stall warming logic is confusing a fact that airbus was told about as for experience, well the cockpit voice recorder confirms the captain asking the reliefs pilot if he had a commercial pilots license!! And the training records are detailed in the report, what's your point
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Old 22-01-2012, 16:18   #299
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Re: Why Integrate the Autopilot ?

Thanks Mark for the explanation of the extra capabilities. That clarified the last 20 pages quite nicely- you should have posted that earlier!(grin) I think that the NMEA2000 is the way to go even though my other instruments are older. It'll be a good reason to upgrade!! Maybe I could move this thread ahead by asking Simrad or Raymarine? Just kidding...
Best regards
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Old 22-01-2012, 16:18   #300
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Originally Posted by sidmon
Again, in spite of some who want to peg my position as either or when it comes to utilizing the latest in nav equipment, what ties the cases cited in the links above is the common elements of "automation addiction ".

In the case of Schettino, that fostered a dangerous sense of complacency and imprudence.

Its not an "either/or" in the use of the latest electronics. Alll I have been trying to point out is that there ARE human factors risks induced by their use.

And any Mariner that is prudent should be aware of them.
Explain how the costa Concordia accident was about " automation addiction"
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