Do I need DME or ADF in an IFR-certified GPS panel?

On Wed, 08 Jun 2005 20:33:53 -0500, No Spam wrote:

Yeah, some of those AWOS units aren't tied into the "real" world.

If you look at http://adds.aviationweather.gov/metars/stations.txt, it's
listed. However, if you go to ADDS, it won't come up as a METAR station.

The ONLY data available is the local altimeter setting. So I would not
expect it to be listed as a METAR station.


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

On Wed, 8 Jun 2005 19:30:01 -0700, "Matt Barrow"
wrote:


"Ron Rosenfeld" wrote in message
.. .

Some GPS units (GNS480) do NOT require that the the alternate have
something other than a GPS approach.

Why is that?



I believe it has to do with the idea that boxes certified under TSO C146,
which includes WAAS and other goodies, are more robust. Take a look at the
1-1-20. Wide Area Augmentation System (WAAS) for a more in-depth
presentation.

As a matter of fact, with a box certified under TSO C146, it is not even
required to have any other navigation equipment on board the aircraft.


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Matt Barrow wrote:
"Ron Rosenfeld" wrote in message
...

Some GPS units (GNS480) do NOT require that the the alternate have
something other than a GPS approach.


Why is that?



Certification to a higher standard.
The 480 is TSO C146c box, the rest are TSO C128a

On Wed, 08 Jun 2005 22:38:59 -0400, Ron Rosenfeld
wrote:

On Wed, 08 Jun 2005 20:25:15 -0500, No Spam wrote:

On 6/8/05 18:40, "Ron Rosenfeld" wrote:

On Tue, 07 Jun 2005 22:20:12 -0500, No Spam wrote:

I see there's a phone number tied to your AWOS - have you tried calling it
airborne with a cell phone?

I was not aware of a phone number; and I just checked the database at
AIRNAV and don't see one listed there or at AOPA. What is it? Where did
you find it? I'll give it a call and see what answers.




Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

http://www.airnav.com/airport/KEPM under "Airport Communications":

WX AWOS-A: 260 (207-853-0997)

- Don

I think that's an old number for the terminal building. A sleepy voice
answered when I dialed it just now :-(

There's no phone number in the AF/D and it doesn't show up on
877-any-awos either.

On Wed, 08 Jun 2005 22:49:00 -0400, Ron Rosenfeld
wrote:

On Wed, 8 Jun 2005 19:30:01 -0700, "Matt Barrow"
wrote:


"Ron Rosenfeld" wrote in message
. ..

Some GPS units (GNS480) do NOT require that the the alternate have
something other than a GPS approach.

Why is that?



I believe it has to do with the idea that boxes certified under TSO C146,
which includes WAAS and other goodies, are more robust. Take a look at the
1-1-20.

That should be the AIM 1-1-20


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Ron Rosenfeld wrote:

On Wed, 08 Jun 2005 14:55:45 -0400, xyzzy wrote:


Doug wrote:


There is, in fact, a requirement to be able to fly the approach at your
alternate without the use of GPS. So having DME will assist you in
finding legal alternates that have VOR/DME approaches. This will allow
you to carry less fuel and more payload. Without DME or ADF, all you
can fly is a VOR approach, and if you have radar, an ILS or LOC (maybe
a few obscure others). Even then some ILS's require DME or ADF.

My home airport has an ILS approach with ADF required, but I just
figured I could use the GPS to substitute for the ADF. From what I
understand of the above, that's true but that also means my airport's
ILS approach is not a legal alternate for someone planning a GPS
somewhere else, do I understand that right? (I'm an instrument
student, still learning this stuff and have found this thread fascinating).


What is your home airport?


TTA, ILS RWY 3.


Some GPS units (GNS480) do NOT require that the the alternate have
something other than a GPS approach. But I'd like to look at your specific
approach to see if it would be legal to fly the ILS ADF approach there.

The other aproaches at TTA are GPS on both 3 and 21 and NDB on 3. So
basically an ADF is kinda important there. If you don't have an
approach certified GPS, you need one.

xyzzy wrote:

Ron Rosenfeld wrote:

On Wed, 08 Jun 2005 14:55:45 -0400, xyzzy wrote:


Doug wrote:


There is, in fact, a requirement to be able to fly the approach at your
alternate without the use of GPS. So having DME will assist you in
finding legal alternates that have VOR/DME approaches. This will allow
you to carry less fuel and more payload. Without DME or ADF, all you
can fly is a VOR approach, and if you have radar, an ILS or LOC (maybe
a few obscure others). Even then some ILS's require DME or ADF.


My home airport has an ILS approach with ADF required, but I just
figured I could use the GPS to substitute for the ADF. From what I
understand of the above, that's true but that also means my airport's
ILS approach is not a legal alternate for someone planning a GPS
somewhere else, do I understand that right? (I'm an instrument
student, still learning this stuff and have found this thread
fascinating).



What is your home airport?


TTA, ILS RWY 3.

Re reading the chart I see that the NDB's location is also identified
with a DME fix on the ILS, so maybe that means ADF is not really
required if you have DME?

xyzzy wrote:
xyzzy wrote:

TTA, ILS RWY 3.


Re reading the chart I see that the NDB's location is also identified
with a DME fix on the ILS, so maybe that means ADF is not really
required if you have DME?

You need ADF or GPS for the missed approach. DGB

Dave Butler wrote:

xyzzy wrote:

xyzzy wrote:


TTA, ILS RWY 3.



Re reading the chart I see that the NDB's location is also identified
with a DME fix on the ILS, so maybe that means ADF is not really
required if you have DME?


You need ADF or GPS for the missed approach. DGB

Duh, thanks. That's why I'm an instrument student, not instrument rated.

Tom Fleischman wrote:
On 2005-06-08 09:52:31 -0400, Ron Natalie said:

I just installed a GNS480/MX20/SL30 combo.


Isn't it sweet!


Yep, and GPSS is way cool it's almost to the point that I've
stopped hovering my hand over the big red AP disconnect button
while it's driving itself around the purple line on the screen.