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  #91   Report Post  
Armond Perretta
 
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Remco Moedt wrote:

GPS might be too precise, though.... I know a few people using a
bouy as a waypoint using a GPS coupled to an autosteer......well,
they sure did find out when that waypoint was reached.....g


Quite a few GPS manuals point out this danger. Even before selective
availability was dropped this was an issue (and not only for LNB's).

--
Good luck and good sailing.
s/v Kerry Deare of Barnegat
http://kerrydeare.home.comcast.net/



  #92   Report Post  
Roger Long
 
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It's a problem with airplanes too. It used to be that planes were
spread out a couple of miles laterally on a route. Now, everyone who
doesn't have the wit to put in some intentional offset is flying down
the same 100 foot wide lane.

--

Roger Long




  #93   Report Post  
Jeff Morris
 
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Jim Donohue wrote:
Calling it a "system" was a euphemism. It was a GPS attached to an
autopilot. They ignored the depth sounder, the radar, and visual cues.
Actually, the same thing could have happened to most anyone with an
Autohelm and a Garmin, except the the Autohelm (now Raymarine) gives a
better indication of faulty input.


Neither the page of causals nor the 3 pages of recommendations has a single
mention of the term GPS...not one. There were a number of failures but not
one that indicates GPS was a problem. Incompetent seamanship is the
proximate cause with poorly designed and poorly operated equipment creating
the opportunity for the incompetent seaman to ground the boat.



You've made this claim several times and its total Bull****! You're
claiming, in essence, that because the satellites broadcast a good
signal, there is no problem with over-reliance on GPS. This is a
textbook case in what can go wrong with such over-reliance.

The bizarre thing here is that on one hand you've been arguing that GPS
should be learned first because it is nearly perfect, but then here
you're claiming that the problem was the "incompetent seaman" who relied
too much on GPS.

In the "Conclusions" section of the report the NTSB describes what
happened and what went wrong. The majority of the 22 conclusions talk
about the failure of the GPS (mentioning it specifically) system or the
failure to double check by other means, i.e. the over-reliance on one
system.

Here's some examples:

5. Had the fathometer alarm been set to 3 meters,
as was the stated practice, or had the
second officer chosen to display the
fathometer data on the control console, he
would have been alerted that the Royal Majesty
was in far shallower water than expected
and, thus, was off course. He would
have been alerted perhaps as long as 40
minutes before the grounding, and the
situation could have been corrected.

6. The watch officers’ monitoring of the status
of the vessel’s global positioning system
was deficient throughout the voyage from
St. George’s.

7. Deliberate cross checking between the
global positioning system and the Loran-C
to verify the Royal Majesty’s position was
not being performed and should have been
on the voyage from St. George’s.

8. Even though it is likely that the watch officers
were not aware of the limitation inherent
in using the position-fix alarm to monitor
the accuracy of GPS position data, it was
inappropriate for them to rely solely on the
alarm to warn them of any problems with
the GPS data.

9. The sighting of lights not normally observed
in the traffic lanes, the second officer’s inability
to confirm the presence of the BB
buoy, and the sighting of blue and white
water should have taken precedence over
the automation display on the central console
and compelled the second officer to
promptly use all available means to verify
his position.

10. The chief officer and the second officer did
not observe good watchkeeping practices or
act with heightened awareness of the precautions
that are needed when a vessel approaches
the Boston traffic lanes and landfall.

11. The master’s methods for monitoring the
progress of the voyage did not account for
the technical capabilities and limitations of
the automated equipment.

12. The watch officers on the Royal Majesty
may have believed that because the global
positioning system had demonstrated sufficient
reliability over 3 1/2 years, the traditional
practice of using at least two independent
sources of position information was
not necessary.

13. 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 report continues with other items in the same vein, though focused
more on the problems with the integrated system and the training, such as:

16. Had the navigation and command system 25
autopilot been configured to compare position
data from multiple independent position
receivers and had a corresponding alarm
been installed that activated when discrepancies
were detected, the grounding of the
Royal Majesty may have been avoided.


Although the "Probable Cause" section which follows does not mention GPS
specifically, it is quite short (two small paragraphs) and mentions
simply "overreliance on the automated features of the integrated bridge
system," the lack of training, and the failure to take "corrective
action after several cues indicated the vessel was off course." In
other words, they relied too much on one source of position (the gps)
and ignored others.

While the "Recommendations" section does not mention GPS specifically,
it clearly recommends against over reliance on one system. We've never
claimed there was anything "wrong" with GPS, only that other forms of
navigation are just as important. The report includes comments like:

Review the bridge watchstanding practices
on all its vessels, and revise, as
necessary, to ensure that all watch officers
adhere to sound watchstanding
practices and procedures, including using
landmarks, soundings, and navigational
aids to verify a vessel’s position,
relying on more than one source for position
information, and reporting to the
master any failure to detect important
navigational aids.
....
As part of the foreign flag passenger
ship control verification examination
program, verify that the watchstanding
procedures of ships’ officers include the
use of multiple independent means of
position verification.

It is true that the bulk of the recommendations have to do with better
standards for automated systems, but even then it deals largely with the
need to use more than one form of input:

comparing position-receiver data for
significant discrepancies between
position receivers, and subsequent
positive annunciation to the crew;

Sorry Jim, its clear that you've been disingenuous with us. The NTSB
study is quite specific in finding fault with relying completely on GPS.
Though they don't fault the GPS system itself (i.e. the signal leaving
the satellite) they make it quite clear the overreliance on one
electronic navigation system was the cause of the grounding.







  #94   Report Post  
otnmbrd
 
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Rodney Myrvaagnes wrote:


We agree on what went on. I would still call it what I did. They
didn't ask the bridge system what input it was using.

Idiots anyway, for all their licenses.



Rodney Myrvaagnes NYC J36 Gjo/a


System checks .... an important pre-departure and daily check that is
becoming more involved.
At any rate, we can disagree on the basic "Centric" fault, the results
were the same.

otn
  #95   Report Post  
otnmbrd
 
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Rodney Myrvaagnes wrote:


According to the report, the loran was behaving correctly near
Nantucket, where it mattered. Nobody believed it.



Rodney Myrvaagnes NYC J36 Gjo/a


G GPS Centric

otn



  #96   Report Post  
Jeff Morris
 
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Jim Donohue wrote:

The question isn't what should be used first; the question is what should
be taught first. Your inability to understand that is beyond jaxian.

Teaching someone GPS before basic piloting is like teaching children how
to use a calculator before teaching them the addition table.


We disagree..not about the need to teach piloting but upon the base on which
you develop that piloting skill. DR is simply the technique that is adopted
between fixes to plot ones position for the period of time until a new fix
is available. But an electronic navigation system provides continuous
position fixes...so DR really has no place.


Absolute nonsense.

LOPs and such come up in
piloting and I agree that one uses whatever is available and reasonable to
maintain a cross check. The eye is a very useful tool for this when
visibility is adequate. Radar also can well provide such a cross check.
When running multiple electronic navigation systems they can cross check
each other. All of these skills should be taught.

I have this strange feeling you guys are taking this position because you
feel, as I do, that GPS based navigation is easier to teach and to do than
non electronic piloting. So the real reason you want non-electronic first
is so the new students have to suffer like you did.


Not at all. My only desire is to have the best navigators out on the
water. Perhaps you should look at the curriculum of the Power Squadron,
or the Coast Guard Auxiliary. Although both offer "quicky" courses for
GPS, acknowledging that many boaters will only tolerate a few hours of
instruction, their full courses follow the tradition path of charts,
compasses, DR and piloting before introducing GPS.


Actually, the case was that someone was learning how to do LOP's and DR
and wasn't interested in LORAN. You called this "utter nonsense." I call
your attitude "sheer stupidity."



So again we disagree. The instructor wanted to teach without the use of the
electronic navigation systems...I consider this nonsense. You end up with a
less trained student who initially is far less able to navigate. Why would
one teach a student to navigate so as to get an inferior outcome at least
during the initial phases of training? I would want them as capable as
possible as early as possible for the sake of their and others safety.


You should re-read the original post and your response.

....

Uhhh where did it state that learning LOPs and DR was "utter nonsense"?
I think I made such a comment about teaching a student navigation with
such techniques emphasized to the exclusion of electronic navigation.
Still do.


Perhaps you should re-read your fist post in this thread. Dave said his
daughter was enjoying learning LOP's and DR, and wasn't interested in the
Loran. Your response was "Ohh stop...what utter nonsense." You went on
to spew more silliness which only served to make you feel important and
make everyone else think you're a fool.


The remark was in the context of claiming to teach navigation without the
electronic systems. Dave was featuring it as a good thing. I believe it a
bad thing. Leads to a new sailor with more limited skills than if taught
the electronic approach up front.


Your approach pretty much guarantees that most students will never learn
the basics. It's a good thing the most teachers disagree with you.



Nowhere was it mentioned that Dave's daughter would not go on to learn
other techniques, or that she was even destined to be a boat's navigator.
It was only stated that she enjoyed learning basic piloting.

Frankly criticizing anyone for wanting to learn almost anything is a mark
of a very small mind.


And you technophobes lack the prospective to see the outcome of your
teaching primary dependence on outdated technology.


Technophobe? I love it! You should realize that 25 years ago I was
programing spacecraft navigation for NASA. I'm now retired from IBM
after spending about 30 years working on cutting edge technology.

I'm not afraid of technology, I just have a realistic view of its
limitations.




The way to do this is to actively practice "manual techniques" even while
using a GPS. I've never known someone who learned GPS first who did this.
However, once you have actually navigated by LOP's, or following depth
contours, or watching "danger bearings," it starts to become automatic.
When I see a buoy line up with a point of land, I mentally follow the line
on the chart and check the depth I should be in. It only takes a second,
but would someone who had never done that "for real" bother to do it?



And it does for electronic navigators as well. You learn to correlate the
views of the eye and other devices with the GPS or whatever.


This is exactly what I've been talking about. My point has been that
those who learn GPS first don't bother to learn this.


Calling it a "system" was a euphemism. It was a GPS attached to an
autopilot. They ignored the depth sounder, the radar, and visual cues.
Actually, the same thing could have happened to most anyone with an
Autohelm and a Garmin, except the the Autohelm (now Raymarine) gives a
better indication of faulty input.


Neither the page of causals nor the 3 pages of recommendations has a single
mention of the term GPS...not one. There were a number of failures but not
one that indicates GPS was a problem. Incompetent seamanship is the
proximate cause with poorly designed and poorly operated equipment creating
the opportunity for the incompetent seaman to ground the boat.


Refer to my other post on this. Its pretty clear that you're blatantly
lying here - the page on conclusions talks mostly about the problem of
relying too much on GPS.

The "Cause" section very short and though it doesn't mention GPS by
name, it is explicit in blaming overreliance on one form of navigation
and ignoring other more basic forms. While the "Recommendations"
section doesn't mention GPS specifically, it is filled mostly with
comments about overreliance on one form. The issue is not that GPS
itself is flawed, its relying on only one form. Thus the
recommendations aren't specific about GPS, they apply to GPS, Loran,
Glosnoss, or any other system that might be used.


So you turn on 3 gps's for a day sail? I think you'd be better served by
brushing up on more basic skills.



No I use 2 GPS for serious navigation and hold a third in reserve. Both
active GPS have the same way points set. The position of the hand held is
plotted on the chart. And all this is cross checked with eye and radar. I
use true headings unless we have to hand steer when we work out the
magnetic.

When I go day sailing in Long Beach I may not crack open a chart or turn on
a GPS. I can drive a boat just like you do. On a clear day in a familiar
port I need little navigation help from anything.


Don't presume what I do - If I'm just taking a spin around the inner
harbor I might not have a chart on deck, but in the outer harbor, which
I've sailed for 40 years, I always have a chart on deck. For longer
trips, or if fog is possible, I'll usually have GPS and radar setup, but
I'll also have pencil, dividers and parallel rules on hand. And at
least one trip I year I leave the GPS and radar below, and formally plot
the course at the helm. I have to get in at least one running fix a year!

When is the last time you did a running fix? Could your "students" do
one if the GPS failed? Do they even know what it is?
  #97   Report Post  
Jeff Morris
 
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otnmbrd wrote:
Rodney Myrvaagnes wrote:



According to the report, the loran was behaving correctly near
Nantucket, where it mattered. Nobody believed it.



Rodney Myrvaagnes
NYC J36 Gjo/a


G GPS Centric


Nobody actually checked the Loran until after the grounding, when it
revealed a 15 mile error. The depth sounder was on but the alarm was
turned off. The radar did not show the entrance buoy in the correct
place, and that was ignored. Lights on Nantucket were seen when they
should have been 30 miles away.

GPS Centric
  #98   Report Post  
Jeff Morris
 
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Dave wrote:
Technophobe? I love it! You should realize that 25 years ago I was
programing spacecraft navigation for NASA. I'm now retired from IBM
after spending about 30 years working on cutting edge technology.

I'm not afraid of technology, I just have a realistic view of its
limitations.


Hear hear. 40 year ago I was writing in assembler for a then
state-of-the-art scientific computer the size of a medium sized desk. 15
years ago, as a hobby, I was writing assembler and a couple of other
languages for a z-80 based machine.

Technophobe indeed.


A Z-80? Wow, 15 years ago that was already obsolete, given that Windows
3 and OS/2 were already running on 486's by then. What are you, a
technophobe??

Let's see, 40 years ago - the IBM 1620 was over the hill, the 1401 was
commonly used but hardly "state of the art." The 7090 was bigger than a
desk, as was the CDC 6600. Maybe the 360, though you would have had to
be special to see one in 1965. I'll guess one of the early Digital's,
like the PDP 7 or 8.
  #99   Report Post  
Jack Dale
 
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On 25 Jan 2005 15:55:04 -0600, Dave wrote:

On Tue, 25 Jan 2005 16:16:50 -0500, Jeff Morris
said:



Yes. On thinking about it it was the early 80s. Remember the Timex Sinclair
and the Tandy TRS-80?


My first was an Osborne Model 1. I thought it was great! The 5 inch
floppies (really floppy) cost $10 (cdn) and held 92K. The screen was
just a bit small.

Jack
  #100   Report Post  
Jeff Morris
 
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Jack Dale wrote:
On 25 Jan 2005 15:55:04 -0600, Dave wrote:


On Tue, 25 Jan 2005 16:16:50 -0500, Jeff Morris
said:



Yes. On thinking about it it was the early 80s. Remember the Timex Sinclair
and the Tandy TRS-80?



My first was an Osborne Model 1. I thought it was great! The 5 inch
floppies (really floppy) cost $10 (cdn) and held 92K. The screen was
just a bit small.

Jack

I remember how everyone was so excited about the Osborne because we
finaly had a portable computer!

The neat thing about the Osborne is that you could program it to make
any format floppy. In those days, each manufacturer had a different
track/sector format - with the Osborne you could create any format.
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