"Jeff Morris" wrote in message
...
Jim Donohue wrote:
"Jeff Morris" wrote in message
...

Jim Donohue wrote:

Anyone who has been on a boat knows that a GPS *DOES NOT* for all
practical purposes work all of the time. I've had a GPS fail several
times, I've seen charting inaccuracies a number of times. Similar things
have happened to almost every cruiser I know.


You lead an unlucky life. I have never seen a significant outage of the
GPS. I follow the tech literature on the subject. Aside from deliberate
military actions the outages are very few, far between, and limited in
time duration. As I said I have never seen one.

You mean, other that the outages that have happened, there have been none?

I'll admit the system has been pretty stable but individual satellites are
taken down which causes minor hiccups. Several weeks ago, my wife's car
GPS was off by a quarter mile for about 5 minutes - I have no idea what
the cause was, but it could have been a problem on a boat.


It is of course possible that you have a source of interference on your
boat. That does happen. It is one of the reasons that multiple GPSs are
sensible. Different devices have different weaknesses. I am sure there
are also some specific locations that have a multi-path problem. Again
though few and far between. GPS ain't perfect but it is very close.
Done with redundant instruments on the open sea it is, for all practical
purposes, perfect.

The problem that has bit me a few times is that I use a handheld which is
connected to its cable every time I use the boat. If the power connection
isn't solid, it can fall back to battery power, and then shut off a few
hours later. I keep spare cables and batteries, but when it happens, I'm
down for a few minutes.

And although I often have a chart cartridge, I've found occasional
"dropouts" in the coverage - rather disconcerting when you're in a tricky
section of the ICW and the chart screen suddenly goes blank.

On my previous boat (Nonsuch 30) I would lose signal sometimes. I assumed
it was from the wishbone boom, but others claimed the antennae was too low
and the signal was blocked by crew members; perhaps both causes were
factors.

I've never been hit by lightning, by I know many others that have, and the
GPS is frequently a victim. I've also heard of GPS's damaged by power
spikes. Actually, the first time I took a GPS on a trip its menu button
was damaged so it was virtually useless.

Having a spare GPS, and batteries, cables, etc. on board is useful and
prudent, but it doesn't help when you lose the primary in a tricky
situation.

While these problems are infrequent, and often "operator error" it does
not mean they don't happen. And having a strategy to cope, such as
carrying a redundant GPS doesn't help you for the time it takes find it
and fire it up.



The present cruiser population is certainly and effectively completely
dependent on GPS for off shore navigation. At this point I don't think
there are many exceptions left. I have not come across a report of a
significant problem with that in a long time.

What's your point? The vast majority of boaters don't go offshore. And
obviously, piloting techniques are not commonly used off shore. You keep
trying to equate piloting with celestial; they're are not the same thing.


Charting inaccuracies are chart problems very close to completely.
Without gps they are hard to detect. The ones on the West coast of
Mexico however are detectible with a good LORAN.

Without GPS the charting inaccuracies would not be as important. As I
mentioned before, I watched a trawler run aground because they trusted the
GPS and didn't watch the depth.





None of these incidents were a major problem for me because I was using
other techniques and was able to recognize the situation and compensate.

The issue here is not which technique is the most accurate, or which
should be used to the exclusion of the other. Continuing to cast it in
these terms make you look like a jaxian fool.


One uses all reasonable methods available. The first and primary of
these is GPS. Your inablity to understand this simple statement is
almost jaxian.

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. 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.



The issue is that you claimed it was foolish to teach someone basic
piloting, even when the person was eager to learn. This attitude marks
you as a complete fool, Jim. I hope I never meet one of your students on
the water.


No my argument was that basic navigation...not piloting...was better
taught with GPS as the primary technique. It was in response to an
individual teaching basic navigation with electronic aids removed.

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.


It is even possible that the individual involved and I would end at the
same end point. Just different routings.

It is remotely possible, but someone who learns how to use a GPS first is
rather unlikely to then learn basic piloting. And this is the essential
point of my argument. Anyone can teach them self how to use a GPS;
learning piloting usually takes instruction and practice. If I only have
a student for a few hours, I'd rather spend time on something that's
harder to learn, and just as important. Most of the concepts of piloting
relate to GPS usage, so nothing is wasted.

And I think that basic piloting is best taught in the GPS centric context.
Once a reasonable skill level is reached one starts on what to do when
something breaks.


And you again utterly misstate my position. GPS is the first skill
taught...it should be the centerpiece of the navigation system. Then
others. Certainly even the dullest of students can learn to check a
chart position via eyeball or radar.

Are you daft, man? Are you claiming now that piloting need not be
taught because "even the dullest" can do it without training? And radar
too? Bizarre, considering you've confessed to have weak radar skills!


Listen carefully. Pilotage is important. One teaches navigation with
the GPS first.

One person might do that, the rest of us will teach properly, thank you.

The first portion of that instruction is the use of charts.

agreed.

A current student however should learn with the GPS positon centric
techniques rather than the LOP techniques of conventional DR.

DR doesn't involve LOPs. Its clear your understanding in this area is
weak.

Yes eventually these get
taught also...but secondary to what is the real world.

Eventually? Yea, right.



You asserted that learning LOP's and DR was "utter nonsense." I think
no one should be trusted with a GPS until the learn these basics.


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.

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.


You correctly point out that it will be difficult to teach DR/LOP after
one learns electronic navigation. That is because it is difficult to
convince the student that sufficient value exists in such techniques.
You deal with this value problem by teaching DR/LOP first.

There's a bit more to it, but OK ...

I claim simple that this in
no way prevents the knowledge of DR/LOP going away real fast. I think we
need to develop that set of DR/LOP skills that will actually stick after
electronic navigation is learned. If we can't develop such a set and
convince the newby of value then the outcome is the same.

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.


I stress the electronic navigation first because I think it more
important they do that well than that they master an initial set of
techniques they will abandon upon learning the electronic version. First
good at the primary system then good at the secondaries.

Too bad the world doesn't work this way. We could teach calculators in
the third grade because the kids could be trusted to learn long division
later.

I introduce VOR/DME and RDF merely to demonstrate that we really don't
propose to teach all available navigation techniques...only those that we
believe useful and reasonable.

There are lots of techniques that are arcane or obsolete. They may be of
interest to the advanced navigator or hobbies, but they are in a different
category from piloting, especially when the equipment isn't often carried
on board.


The NTSB study blamed several "probable causes:" over reliance on GPS,
and lack of training of the officers, and the failure to recognize the
problem from other cues. This is a perfect example of problem with your
approach. Claiming that your strategy works, but in this case they were
incompetent is foolish.

http://www.ntsb.gov/publictn/1997/MAR9701.pdf


I am reasonably familiar with the report. Find for me any mention of
over reliance on GPS. It does find fault with over reliance on the
automatic features of integrated bridge systems.

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.

It also discusses flaws in the design of such systems. I agree that
total reliance on a single GPS is not wise. I generally run three...and
two are active in the process to try to avoid the entry errors that I
believe are the worst problems with GPS navigation. When the europeans
get their system operative or the Russians complete theirs I will almost
certainly run one GPS off another system. I will also use other inputs
like depthsounders and radar to help prevent errors.

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.

But running to Catalina in the dark..chart open,,, two GPSs up and going as
well as radar for collisiion avoidance.