IFR with a VFR GPS

"Jose" wrote in message
news

Well, actually it could. Any navigation system which tells the pilot he
is in one place when he is actually in another, which is used by a pilot
who is in IMC, could cause the pilot to place himself in a position from
which a collision with a mountainous surprise is unavoidable. While it is
true that the navigation system did not move the mountain, the effect on
the pilot is the same.


The controller will alert the pilot to the navigational error. The use of a
handheld GPS for IFR enroute navigation in US controlled airspace is no more
hazardous than being vectored.



It may be that a VFR GPS which is clipped to the right part of the yoke
will provide better guidance in and among ridges than an IFR ADF. But
there is a risk, not present with an IFR installation of anything, that
the highly accurate VFR GPS unit will fall off the yoke at the wrong
moment, perhaps while outside of radar coverage, or on an approach.


We're talking about enroute use, not approaches. If the aircraft is out of
radar contact it will be routed via airways or within the usable limits of
navaids. The pilot will be able to compare the GPS to his VOR or ADF to
verify it's accuracy. The use of a handheld GPS for IFR enroute navigation
in US controlled airspace is no more hazardous than use of VOR along
airways.



There
is a risk (present in VFR and IFR units) that the data displayed is
incorrect - it has happened in our aircraft (Danbury moved four hundred
miles without giving any notice to Ridgefield); IFR units are (presumably,
though only the manufacturer really knows) tested to higher standards.
There is a risk that the pilot will be unable to maintain the more
challenging scan required by certain VFR GPS "installations" and thus will
end up elsewhere than where he thought he was. Outside of a radar
environment, in hostle terrain, this could activate the ELT.


The controller will alert the pilot to the navigational error. The use of a
handheld GPS for IFR enroute navigation in US controlled airspace is no more
hazardous than being vectored. If the aircraft is out of radar contact it
will be routed via airways or within the usable limits of navaids. The
pilot will be able to compare the GPS to his VOR or ADF to verify it's
accuracy. The use of a handheld GPS for IFR enroute navigation in US
controlled airspace is no more hazardous than use of VOR along airways.



As for relying on controllers to "nudge" the aircraft back on course in a
radar environment, this would be true primarily in airspace controlled by
Steven P. McNicoll, who mever nakes mistakes. Merely human controllers
might, for any number of reasons incomprehensible to Steven, miss
something, allowing the pilot's error to terminate the flight prematurely.


It is not an option, it is required of all controllers. If you can't trust
the controller to perform his job as he is required to do you cannot operate
IFR in controlled airspace.

I am talking about relying on a VFR GPS. You are talking about "using"
it, like using a tuna fish sandwich.

In a situation where primary navigation instruments (e.g. VOR) are
available to the pilot and his clearance, I see no problem =using= a VFR
GPS. In a situation where radar vectors are being provided, I also see
no problem =using= a VFR GPS.

In a situation where radar vectors could be available, but are not being
provided, one is relying on the controller to do something that the
controller may not be doing. I assume that there is a little more
monitoring of vectored aircraft than "own navigation" aircraft; the
controller is depending on the pilot to navigate if a vector is not
being provided.

In a situation where radar coverage does not exist, and navigation is
(therefore) via airways or within the usable limits of naviads, those
navaids do no good if the pilot does not tune them in. This is the
difference between =using= and =relying= on equipment which dominates so
many of these threads. I see no problem using the standard navaids
along with a VFR GPS. You probably agree here. I do see a problem
using a VFR GPS and =not= using any other navaids in this situation;
this is what I call "relying on" a VFR GPS. Your position on =this= is
unclear because of the way you conflate the concepts "use" and "rely on"
in your writing, and because of your statement

The pilot will be able to compare the GPS
to his VOR or ADF to verify it's accuracy.

in support. (btw, it's "its") This tells me we're talking about two
different things while pretending they are the same.

The FAA does not prohibit the use of a VFR GPS or a tuna fish sandwich
in IFR or IMC. It does prohibit relying on a VFR GPS, and it prohibits
relying on a tuna fish sandwich in the same situation.

Do you agree or disagree with the FAA's stance here?

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

"Jose" wrote in message
. ..

I am talking about relying on a VFR GPS. You are talking about "using"
it, like using a tuna fish sandwich.


Start a new thread. This discussion is about the use of a handheld GPS for
IFR enroute navigation in US controlled airspace.



In a situation where radar vectors could be available, but are not being
provided, one is relying on the controller to do something that the
controller may not be doing. I assume that there is a little more
monitoring of vectored aircraft than "own navigation" aircraft; the
controller is depending on the pilot to navigate if a vector is not being
provided.


One is relying on the controller to do his job as he is required to do. The
controller is required to provide radar monitoring and course guidance, if
necessary, if the route is not on airways or within the usable limits of
navaids.



In a situation where radar coverage does not exist, and navigation is
(therefore) via airways or within the usable limits of naviads, those
navaids do no good if the pilot does not tune them in.

Careful, you're approaching idiocy.



This is the difference between =using= and =relying= on equipment which
dominates so many of these threads. I see no problem using the standard
navaids along with a VFR GPS. You probably agree here. I do see a
problem using a VFR GPS and =not= using any other navaids in this
situation; this is what I call "relying on" a VFR GPS. Your position on
=this= is unclear because of the way you conflate the concepts "use" and
"rely on" in your writing, and because of your statement

The pilot will be able to compare the GPS to his VOR or ADF to verify
it's accuracy.

in support. (btw, it's "its") This tells me we're talking about two
different things while pretending they are the same.


No, we've been talking about use of handheld GPS for IFR enroute navigation
in US controlled airspace.



The FAA does not prohibit the use of a VFR GPS or a tuna fish sandwich in
IFR or IMC. It does prohibit relying on a VFR GPS, and it prohibits
relying on a tuna fish sandwich in the same situation.

Do you agree or disagree with the FAA's stance here?


Post the FAA's statement. I never suggested relying exclusively on VFR GPS,
it was I that pointed out one is NOT relying exclusively on a VFR GPS when
one is using a handheld GPS for IFR enroute navigation in US controlled
airspace.

I am talking about relying on a VFR GPS. You are talking about "using"
it, like using a tuna fish sandwich.
Start a new thread. This discussion is about the use of a handheld GPS for
IFR enroute navigation in US controlled airspace.

You sure you weren't a lawyer in a previous life?

Careful, you're approaching idiocy.

It was necessary.

No, we've been talking about use of handheld GPS for IFR enroute navigation
in US controlled airspace.
[...] I never suggested relying exclusively on VFR GPS

Ok. We are (and always have been) in agreement.

But really... you do better than Clinton.

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

In article ,
Jose wrote:

I am talking about relying on a VFR GPS. You are talking about "using"
it, like using a tuna fish sandwich.
Start a new thread. This discussion is about the use of a handheld GPS for
IFR enroute navigation in US controlled airspace.

You sure you weren't a lawyer in a previous life?

Careful, you're approaching idiocy.

It was necessary.

No, we've been talking about use of handheld GPS for IFR enroute navigation
in US controlled airspace.
[...] I never suggested relying exclusively on VFR GPS

Ok. We are (and always have been) in agreement.

Oh, Jose, you're giving up too easily!

One of the (many) risks of UAHGPSFIFRENIUSCAS (you figure it out) is
that a pilot might become complacent about using his primary navaids,
particularly off-airways since the constant VOR twiddling required for
off-airway navigation is such a pain in the ass and the use of the GPS
is so effortless and (almost invariably) reliable.

Yes, complacency is a form of incompetence. But that does make it any
less of a risk. Pilot complacency, in all its many manifestations, is a
widely recognized risk. Furthermore (and this is the important part)
this particular form of complacency CANNOT MANIFEST ITSELF EXCEPT WHEN A
HANDHELD GPS IS IN USE. That makes it reasonable to assign at least
part of the causality to the use of the GPS.

rg

"Ron Garret" wrote in message
...

Oh, Jose, you're giving up too easily!

One of the (many) risks of UAHGPSFIFRENIUSCAS (you figure it out) is
that a pilot might become complacent about using his primary navaids,
particularly off-airways since the constant VOR twiddling required for
off-airway navigation is such a pain in the ass and the use of the GPS
is so effortless and (almost invariably) reliable.


But off-airways flight doesn't require any VOR twiddling. You don't have to
monitor your position with any other navaids if you don't want to. You can
rely on ATC for radar monitoring and, if necessary, course guidance.

You say there are many risks in UAHGPSFIFRENIUSCAS. Could you please
identify some of them? Even one would be nice, I've been asking this
question for nearly ten years now and nobody has identified one yet.



Yes, complacency is a form of incompetence. But that does make it any
less of a risk. Pilot complacency, in all its many manifestations, is a
widely recognized risk. Furthermore (and this is the important part)
this particular form of complacency CANNOT MANIFEST ITSELF EXCEPT WHEN A
HANDHELD GPS IS IN USE. That makes it reasonable to assign at least
part of the causality to the use of the GPS.


Why can't that particular form of complacency manifest itself when on a
long-range vector?

The pilot can always ask ATC for navigational assistance, but they
can't provide an inflight snack.

OTFL

I've been asking this
question for nearly ten years now and nobody has identified one yet.

Why do you keep asking this question? Surely it is not to acquire
information, or to dispense any. Rather, you seem to be pressing the
point that "use" and "rely on" are not the same.

Do you think this is a point not understood by other participants here?

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

In article et,
"Steven P. McNicoll" wrote:

"Ron Garret" wrote in message
...

Oh, Jose, you're giving up too easily!

One of the (many) risks of UAHGPSFIFRENIUSCAS (you figure it out) is
that a pilot might become complacent about using his primary navaids,
particularly off-airways since the constant VOR twiddling required for
off-airway navigation is such a pain in the ass and the use of the GPS
is so effortless and (almost invariably) reliable.


But off-airways flight doesn't require any VOR twiddling.

It does if you're out of radar coverage. So the essential elements of
the risk a

1. No radar coverage (or a controller not paying attention, which has
also been known to happen)
2. Pilot decides to rely on GPS alone for guidance (complacency) and
3. GPS fails silently.

Granted, it's not a large risk. But it is possible, and it is possible
ONLY in the presence of a VFR-only GPS.

You say there are many risks in UAHGPSFIFRENIUSCAS. Could you please
identify some of them?

I just identified one. I identified another in another branch of this
this thread.

BTW, just because the risks are numerous does not mean that they are
significant. (But just because they are not significant does not mean
that they do not exist.)

Yes, complacency is a form of incompetence. But that does make it any
less of a risk. Pilot complacency, in all its many manifestations, is a
widely recognized risk. Furthermore (and this is the important part)
this particular form of complacency CANNOT MANIFEST ITSELF EXCEPT WHEN A
HANDHELD GPS IS IN USE. That makes it reasonable to assign at least
part of the causality to the use of the GPS.


Why can't that particular form of complacency manifest itself when on a
long-range vector?

Because you can't decide to stop using your VORs and use your GPS
instead if you do not have a GPS. Isn't that obvious?

You are using up your quota of stupid questions.

rg

Ron Garret wrote:

One of the (many) risks of UAHGPSFIFRENIUSCAS (you figure it out) is
that a pilot might become complacent about using his primary navaids,
particularly off-airways since the constant VOR twiddling required for
off-airway navigation is such a pain in the ass and the use of the GPS
is so effortless and (almost invariably) reliable.

Exactly my point that got me labeled an idiot by McNicoll.

--
Peter
























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Jose wrote:

The FAA does not prohibit the use of a VFR GPS or a tuna fish sandwich
in IFR or IMC. It does prohibit relying on a VFR GPS, and it prohibits
relying on a tuna fish sandwich in the same situation.

"N56789 cleared TUNA 36L"

I think I heard that in a Hot Shots movie...


-m
--
## Mark T. Dame
## VP, Product Development
## MFM Software, Inc. (http://www.mfm.com/)
"There are always alternatives."
-- Star Trek: Spock, "The Galileo Seven"