IFR use of handheld GPS

"Ron Lee" wrote in message
...
I have argued with Ron before that, given reasonable, personal integrety
checks, I would be safer flying a VOR overlay approach with my Garmin
296 than with a light tin VOR receiver.

I won't disagree that when each system is working properly, an
approach with GPS (especially a moving map), is easier (thus perhaps
safer) than a VOR approach. But the point is that if a GPS satellite
malfunctions all bets are off. Hence the need for RAIM or equivalent.

Ron Lee


Is RAIM the only thing that can do that job?

Does WAAS identify a failed satellite and compensate for it?

"Ted" wrote:


"Ron Lee" wrote in message
...
I have argued with Ron before that, given reasonable, personal integrety
checks, I would be safer flying a VOR overlay approach with my Garmin
296 than with a light tin VOR receiver.

I won't disagree that when each system is working properly, an
approach with GPS (especially a moving map), is easier (thus perhaps
safer) than a VOR approach. But the point is that if a GPS satellite
malfunctions all bets are off. Hence the need for RAIM or equivalent.

Ron Lee


Is RAIM the only thing that can do that job?

Does WAAS identify a failed satellite and compensate for it?

Yes WAAS takes care of the integrity requirement.

Ron Lee

wrote:

Ron Lee wrote:

Yes WAAS takes care of the integrity requirement.

Even on a handheld like the Garmin 296/396 models?

You need to consult the manual. If they use WAAS it would seem
logical to take advantage of the WAAS integrity functionality. That
does not make them suitable for IFR use.

Ron Lee

"Ron Lee" wrote in message
...
wrote:

You need to consult the manual. If they use WAAS it would seem
logical to take advantage of the WAAS integrity functionality. That
does not make them suitable for IFR use.


Why not?

wrote:
Ron Lee wrote:


Yes WAAS takes care of the integrity requirement.


Even on a handheld like the Garmin 296/396 models?


Because it is a VFR unit, you have no assurance that the method by which
the 296/396 employs WAAS provides the required integrity.

Unless Garmin has a presence on this forum, no one can answer your
question with much of anything other than opinions.

The folks are Garmin who engineer the aviation handhelds are part of the
same group that make GPS units for hikers, automobiles, etc; i.e. what
Garmin calls the "Consumer Products" group.

Sam Spade wrote:

wrote:
Ron Lee wrote:

Yes WAAS takes care of the integrity requirement.

Even on a handheld like the Garmin 296/396 models?

Because it is a VFR unit, you have no assurance that the method by which
the 296/396 employs WAAS provides the required integrity.

Unless Garmin has a presence on this forum, no one can answer your
question with much of anything other than opinions.

The folks are Garmin who engineer the aviation handhelds are part of the
same group that make GPS units for hikers, automobiles, etc; i.e. what
Garmin calls the "Consumer Products" group.

Thanks Sam. Hopefully one of my responses was not misleading. WAAS
does make up for aviation integrity requirements that are not designed
into current GPS satellites. But for IFR flight, it assumes the
proper user equipment as well (I forget the applicable TSO).

Ron Lee

"Steven P. McNicoll" wrote in message
nk.net...

"Ron Lee" wrote in message
...
wrote:

You need to consult the manual. If they use WAAS it would seem
logical to take advantage of the WAAS integrity functionality. That
does not make them suitable for IFR use.


Why not?


Because it would offend Allah!

As you say, part 95 governs IFR altitudes - not tracking airways. It does
not define airways nor how to track them. It defines altitudes to be used
when on and off airways.

Part 95 is irrelevant to the discussion at hand. There are no regulations
that prohibit the use of a non-certified GPS in IFR flight.

--
-------------------------------
Travis
Lake N3094P
PWK


"Sam Spade" wrote in message
news:eN%7g.176004$bm6.15516@fed1read04...
Travis Marlatte wrote:

Part 95 is what? Regulatory? I agree.

Part 95 talks about altitudes, not tracking airways. Part 95 talks about
altitudes in Alaska. Not the lower 48.

Part 95 is irrelevant to the discussion at hand.

You don't understand how Part 95 works.

Part 95 governs IFR Altitudes in all 50 states and other areas under FAA
jurisdiction, not just Alaska. Where did you get the idea it covers only
Alaska?

IFR Alitudes = MEAs, MRAs, MOCAs, MCAs. Those are the altitudes of
airways. Airways are issued under Part 95 via the federal register via
incorporation by reference, exactly like instrument approach procedures
(Part 97).

The *regulatory* source document for an airway specifies the required VOR
stations, among other things.

The analogy is a VOR approach at PDQ Airport. You cannot fly that
approach using ADF, for example.

Travis Marlatte wrote:
As you say, part 95 governs IFR altitudes - not tracking airways. It does
not define airways nor how to track them. It defines altitudes to be used
when on and off airways.

I never said it governs tracking of airways. It does govern the ground
facilities you must use to track the airway; i.e., from "VOR ABC to VOR
DEF." Apparently, you don't understand that.

Part 95 is irrelevant to the discussion at hand. There are no regulations
that prohibit the use of a non-certified GPS in IFR flight.


That is your statement of opinion, which is not shared by everyone,
including those at the FAA who control this stuff.

Ron Lee wrote:

Sam Spade wrote:


wrote:

Ron Lee wrote:


Yes WAAS takes care of the integrity requirement.

Even on a handheld like the Garmin 296/396 models?


Because it is a VFR unit, you have no assurance that the method by which
the 296/396 employs WAAS provides the required integrity.

Unless Garmin has a presence on this forum, no one can answer your
question with much of anything other than opinions.

The folks are Garmin who engineer the aviation handhelds are part of the
same group that make GPS units for hikers, automobiles, etc; i.e. what
Garmin calls the "Consumer Products" group.


Thanks Sam. Hopefully one of my responses was not misleading. WAAS
does make up for aviation integrity requirements that are not designed
into current GPS satellites. But for IFR flight, it assumes the
proper user equipment as well (I forget the applicable TSO).

Ron Lee

145 and 146 I believe.