IFR with a VFR GPS

"Ron Garret" wrote in message
...

Because if you hit terrain (you were aware that "cumulo granite" is a
euphemism for terrain, yes?) you are unlikely to survive. And if you
survive you are unlikely to escape serious injury. And your airplane is
likely to be totaled as well. That to my mind qualifies as a hazard.

Isn't that obvious?


That's all true, but it's true of all flight. The use of a handheld GPS for
IFR enroute navigation in US controlled airspace is not going to cause a
mountain to appear in front of you or wrest control of the aircraft away
from you and dive it into the ground.

The use of a handheld GPS for
IFR enroute navigation in US controlled
airspace is not going to cause a
mountain to appear in front of you

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.

I suppose the real risk of using^H^H^H^H^Hrelying on a VFR GPS is not
one of collision (this is a risk inherent in any navigation system) but
one of paperwork. If a pilot uses an IFR GPS and it misleads him into a
mountain of granite (or sandstone, or shale), the dead pilot can claim
that the fault does not lie with him. OTOH, if relying on a VFR GPS
causes him meet the same fate, a mountain of paperwork sufficient to
delay his appearances at the pearly gates will appear before him.

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.
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.

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.

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

"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

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"

[the FAA] prohibits relying on a tuna fish sandwich in the same situation.

"N56789 cleared TUNA 36L"

You can't fly a tuna fish approach unless you have a working ham
sandwich as a backup.

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
...

Because if you hit terrain (you were aware that "cumulo granite" is a
euphemism for terrain, yes?) you are unlikely to survive. And if you
survive you are unlikely to escape serious injury. And your airplane is
likely to be totaled as well. That to my mind qualifies as a hazard.

Isn't that obvious?


That's all true, but it's true of all flight. The use of a handheld GPS for
IFR enroute navigation in US controlled airspace is not going to cause a
mountain to appear in front of you or wrest control of the aircraft away
from you and dive it into the ground.

And there are no other possible ways to hit terrain?

rg