IFR use of handheld GPS

In navigator training back when we actually used a sextant, whenever
our mission called for legs using celestial navigation ATC would give
us a celnav clearance. This allowed us much more airspace than a
"direct" clearance as celestial nav was less precise than other methods
of navigation. On missions which required students to use only ded
reckoning, the pilot would also ask ATC for a celnav clearance in order
to have the freedom to manuever (i.e. wander) off the direct line to
the next turnpoint. Thus, when ATC sends you direct to a point, they
expect you to be pretty darn close to staying on the direct course to
that point. If you decide that your going to use a watch and compass
(dr) or pull out a sextant and you wander significantly off that
straight line and stray into restricted airspace--guess who's going to
get violated?

"150flivver" wrote in message
oups.com...

In navigator training back when we actually used a sextant, whenever
our mission called for legs using celestial navigation ATC would give
us a celnav clearance. This allowed us much more airspace than a
"direct" clearance as celestial nav was less precise than other methods
of navigation.


Yes, but probably not as less precise as you think!

"William L.Snow, PE" wrote in message
. ..

Simply said, ifr use of vfr gps is not in the spirit of the far's.

Which FARs?

On Wed, 3 May 2006 19:55:06 -0400, "William L.Snow, PE"
wrote:

Simply said, ifr use of vfr gps is not in the spirit of the far's.

Is it or isn't it? Think about it for a minute.

You can file IFR accept an IFR direct clearance by simply flying
vectors, so it matters little what you have in the plane for equipment
as long as you have the equipment necessary to make any required
approache(s)

Let's say there is a 100 miles of rain between where I am now which is
CAVU and my destination is CAVU. I have enough gas to turn around and
come back home if need be and I have only the minimum required
instruments for legally fly in IMC.

I see the storm ahead, air file, ATC gives me a vector or vectors as
need be. I come out the other side of the storm and close the flight
plan although I have in the real world had them ask that I stay with
them until the destination is in sight and VFR.

This is strictly legal when in a RADAR environment.

Now say I have my trusty 296 with me. I still file with the same
equipment suffix as I would have used without the 296. I am legal in
every sense of the FARs and in addition I have a backup hand held GPS
which I can use for my position and course and ATC is happy to have me
do so. I do not need to tell them I have GPS. I can request direct
and they can tell me cleared direct or direct when able to where ever
with out a request from me. I can accept said "cleared direct", reply
"unable, or request vectors.

Now in real life I happen to have RNAV (not GPS). I have the
equipment go from point A to point B in the system be it direct, by
vectors, or airways which meets the intent of the FARs. That I choose
to do so by following my 296 is immaterial as I have all of the
equipment in the plane to meet the equipment suffix I used when
filing.

If the internal batteries in the 296 die, and I've forgotten the
lighter plug adapter, it is my responsibility to be able to properly
fly the clearance even if it is done by requesting vectors. However I
have a panel full of *stuff* that should enable me to do so without
having to request vectors if I have been paying attention and I keep
everything set up including the ADF to watch stations along the route.

The thing I've never figured out is whey do they bother with "enroute
certified GPS" when there is no need for enroute certified GPS UNLESS
this pertains specifically to panel mounted instruments.
You don't need enroute certified anything as long as you are in RADAR
contact and you can not get a direct clearance if you are not in RADAR
contact regardless of what ever certified equipment you have..

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

You are not allowed to use an IFR-certified GPS for en route (domestic
airspace) in a non-radar environment except with the special Alaska
provisions.

The fact that ATC may clear you via direct via RNAV when non-radar does
not relieve you of your regulatory responsibilites.

Roger wrote:

On Wed, 3 May 2006 19:55:06 -0400, "William L.Snow, PE"
wrote:


Simply said, ifr use of vfr gps is not in the spirit of the far's.


Is it or isn't it? Think about it for a minute.

You can file IFR accept an IFR direct clearance by simply flying
vectors, so it matters little what you have in the plane for equipment
as long as you have the equipment necessary to make any required
approache(s)

Let's say there is a 100 miles of rain between where I am now which is
CAVU and my destination is CAVU. I have enough gas to turn around and
come back home if need be and I have only the minimum required
instruments for legally fly in IMC.

I see the storm ahead, air file, ATC gives me a vector or vectors as
need be. I come out the other side of the storm and close the flight
plan although I have in the real world had them ask that I stay with
them until the destination is in sight and VFR.

This is strictly legal when in a RADAR environment.

Now say I have my trusty 296 with me. I still file with the same
equipment suffix as I would have used without the 296. I am legal in
every sense of the FARs and in addition I have a backup hand held GPS
which I can use for my position and course and ATC is happy to have me
do so. I do not need to tell them I have GPS. I can request direct
and they can tell me cleared direct or direct when able to where ever
with out a request from me. I can accept said "cleared direct", reply
"unable, or request vectors.

Now in real life I happen to have RNAV (not GPS). I have the
equipment go from point A to point B in the system be it direct, by
vectors, or airways which meets the intent of the FARs. That I choose
to do so by following my 296 is immaterial as I have all of the
equipment in the plane to meet the equipment suffix I used when
filing.

If the internal batteries in the 296 die, and I've forgotten the
lighter plug adapter, it is my responsibility to be able to properly
fly the clearance even if it is done by requesting vectors. However I
have a panel full of *stuff* that should enable me to do so without
having to request vectors if I have been paying attention and I keep
everything set up including the ADF to watch stations along the route.

The thing I've never figured out is whey do they bother with "enroute
certified GPS" when there is no need for enroute certified GPS UNLESS
this pertains specifically to panel mounted instruments.
You don't need enroute certified anything as long as you are in RADAR
contact and you can not get a direct clearance if you are not in RADAR
contact regardless of what ever certified equipment you have..

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

You are not allowed to use an IFR-certified GPS for en route (domestic
airspace) in a non-radar environment except with the special Alaska
provisions.

Perhaps you meant to say you're not allowed to fly off-airway?

If you really meant what you said, please explain / cite the rule.

Dave Butler wrote:


You are not allowed to use an IFR-certified GPS for en route (domestic
airspace) in a non-radar environment except with the special Alaska
provisions.


Perhaps you meant to say you're not allowed to fly off-airway?

If you really meant what you said, please explain / cite the rule.

Part 95, IFR Altitudes establishes MEAs and is the authority for airways
and Jet Routes. Those airways are rules, just like an instrument
approach procedure is a rule.

With instrument approach procedures (in addition to RNAV/GPS IAPs) you
have VOR and NBD IAPs that are approved for overlay flight with GPS.
That is the authorization to substitute GPS for VOR, where authorized on
the chart.

You don't have any overlay (i.e., standalone, non-radar) authorization
fo Victor Airways or Jet Routes. Thus, if you are not in a radar
environment you cannot use RNAV as primary for Victor airways or Jet Routes.

Does anyone care? Only if something goes wrong.

There are a few Q Routes, which are predicated solely on RNAV, but thus
far they have been established where traffic volumne is high and radar
is available. They are pretty much for the airlines in the lower 48,
thus far. And, I believe they are all in the high altitude stratum.

As I said before, Alaska has a special authorization that specifically
permits GPS/RNAV overlay of Victor airways.

"Sam Spade" wrote in message
news:2Xx6g.175203$bm6.65816@fed1read04...

You are not allowed to use an IFR-certified GPS for en route (domestic
airspace) in a non-radar environment except with the special Alaska
provisions.


Nonsense.

So, the initial purpose of this thread was to discuss whether or not one
could use a handheld GPS for IFR navigation. Lots of people have been
tossing around lots of opinions with little or no references to rules or
guidance to back them up (hardly surprising...this is usenet after all...)

Anyway, for my own personal edification and enlightenment, I went and
tracked down the official FAA Advisory Circular that specifies what
the requirements are for the use of GPS under IFR. It's entitled
"Airworthiness Approval of Navigation or Flight Management Systems
Integrating Multiple Navigation Sensors", and is FAA AC 20-130A.
It's about as exciting to read as the dictionary (again, hardly
surprising). However, the Gleim Instrument Pilot Flight Manueuvers and
Practical Test Prep guide (which is where I found the reference in the
first place) does a nice job of summarizing the requirements for use of
GPS under IFR as specified in AC 20-130A. It states:

Authorization to conduct any GPS operation under IFR requires that:
a) GPS navigation equipment used must be FAA-approved and the installation
must be done in accordance with FAA requirements
i) Approval for the use of the GPS for IFR operations, and any
limitations, will be found in the airplane's POH (also called
the FAA-approved Airplane Flight Manual) and the airplane's
logbook
ii) VFR and hand-held GPS systems are not authorized for IFR
navigation, for instrument approaches, or as a principle
instrument flight references. During IFR operations, they
may be considered only an aid to situational awareness.

Aircraft using GPS navigation equipment under IFR must be equipped with an
approved and operational alternate means of navigation appropriate to the
flight.
a) Active monitoring of the alternative navigation equipment is not required
if the GPS receiver uses RAIM for integrity monitoring.
b) Active monitoring of the alternative navigation equipment is required
when the RAIM capability of the GPS equipment is lost.

This seems fairly clear to me.....

-- Dane

Steven P. McNicoll wrote:

"Sam Spade" wrote in message
news:2Xx6g.175203$bm6.65816@fed1read04...

You are not allowed to use an IFR-certified GPS for en route (domestic
airspace) in a non-radar environment except with the special Alaska
provisions.



Nonsense.


Where is your reference that GPS is primary for sole means en route
navigation?