I am thinking seriously about getting the GNS480 and need opinions to
(try and) change my mind. The GNS 430 is nice but the 480 has more
features that I like. Anybody using one and making approaches? With
autopilot? with GPSS? Does GPS altitude REALLY work?

Yes to all those questions, except that I don't have GPSS.
Others do have GPSS, and I'm told it works great.

A note regarding the autopilot question...
Our autopilots can capture the GPS glideslope only on approaches
which list VNAV minima.
For LNAV approaches without VNAV minima, if the profile
shows a dotted line representing the glidepath angle (most do),
the GNS480 presents an HSI-like display with vertical guidance,
but that vertical guidance is not sent to the external GS pointer,
thus preventing the autopilot from locking onto the glideslope.
Lateral guidance, of course, remains available to the autopilot.

"RonLee" > wrote in message =
...
>I am thinking seriously about getting the GNS480 and need opinions to
> (try and) change my mind. The GNS 430 is nice but the 480 has more
> features that I like. Anybody using one and making approaches? With
> autopilot? with GPSS? Does GPS altitude REALLY work?

I don't know where you are located but Carolina Avionics in Salisbury,
NC (RUQ) put in a 530 for the same price as a 430. Not a reman or
refurbish. In fact, I had the same pricing on another 530 in when I bought
another A36 Bo'.

I don't work for them, I just like good service and value.

FWIW, the WAAS and terrain s/b put next year. For the difference in
screen size and added functions, I would go w/ a 530, if I could.

Victor J. (Jim) Osborne, Jr.


ps: If you do call the, tell Bill (Smoot) I said to call, he should
remember me.
N100DA & N326DK

On Tue, 28 Dec 2004 23:26:58 GMT, RonLee > wrote:

>I am thinking seriously about getting the GNS480 and need opinions to
>(try and) change my mind. The GNS 430 is nice but the 480 has more
>features that I like.

>Anybody using one and making approaches?

Yes

>With autopilot?

Yes

>with GPSS?

Don't have that.

>Does GPS altitude REALLY work?

What do you mean by that?

The GPS glide slope really works for those approaches for which it is
enabled.

The GPS altitude varies from the pressure altitude due to earth shape
assumptions, and other factors including temperature.

However, my install included an encoding altimeter with a 10 ft resolution.
This allow baro-VNAV approaches. It also allows the pressure altitude to
be read directly on the display.

I, too, chose the 480 over the 430 (as well as over the 530) because of
WAAS, the ability to enter flight plans using airways, TSO146
certification. It has a better display than the 430, although smaller than
the 530.



--ron

RonLee wrote:
> I am thinking seriously about getting the GNS480 and need opinions to
> (try and) change my mind. The GNS 430 is nice but the 480 has more
> features that I like.

Anybody using one and making approaches?

Yes

With autopilot?

Yes

with GPSS?

Yes

Does GPS altitude REALLY work?

Yes, but it does not matter, since wrong or right, baro altitude is what
the IFR system uses.

I can't comment on the 480. It has WAAS, but so will the 480. The 480
has no HSI, but there isn't room for it on the display, and in any case,
I have a real HSI, and an electronic HSI cannot emulate a true HSI
in any case.

Great, I just started the "real vs. fake" HSI argument again :-)

--
Samiam is Scott A. Moore

Personal web site: http:/www.moorecad.com/scott
My electronics engineering consulting site: http://www.moorecad.com
ISO 7185 Standard Pascal web site: http://www.moorecad.com/standardpascal
Classic Basic Games web site: http://www.moorecad.com/classicbasic
The IP Pascal web site, a high performance, highly portable ISO 7185 Pascal
compiler system: http://www.moorecad.com/ippas

Good does not always win. But good is more patient.

"Scott Moore" > wrote in message =
news:GdKBd.8300$wu4.6369@attbi_s52...
> RonLee wrote:
>=20
>> Does GPS altitude REALLY work?
>=20
> Yes, but it does not matter, since wrong or right, baro altitude is =
what
> the IFR system uses.
>=20
> I can't comment on the 480. It has WAAS, but so will the 480. The 480
> has no HSI, but there isn't room for it on the display, and in any =
case,
> I have a real HSI, and an electronic HSI cannot emulate a true HSI
> in any case.
>=20
> Samiam is Scott A. Moore
>=20

WAAS/GPS altitude is used for VNAV approaches.
It works very well, really.
Baro-VNAV is beyond the scope of the CNX80/GNS480.

I'm curious why you say that the 480 has no room for an HSI display.
Have you never seen its NAV page?
I, too, have a "real" HSI in the lower half of my flight director,
but the HSI page in my CNX80 remains useful to me.
As I've posted earlier, the glide-slope needle in my Flight Director
is not driven from the CNX80/GNS480 unless VNAV minima are published.
This defeats autopilot coupling to the computed glideslope on =
non-precision approaches.
However, the HSI display of the NAV page shows vertical guidance
for most LNAV approaches, as a welcome aid for stabilized descents.

"John R. Copeland" > wrote:

> As I've posted earlier, the glide-slope needle in my Flight Director
> is not driven from the CNX80/GNS480 unless VNAV minima are published.
> This defeats autopilot coupling to the computed glideslope on
> non-precision approaches. However, the HSI display of the NAV page
> shows vertical guidance for most LNAV approaches, as a welcome aid for
> stabilized descents.
>

I just took delivery on my GNS480 upgrade, and in the initial test flight, did not see what you are
experiencing. We flew the GPS23 approach into P08 (Coolidge, AZ), and the GPS07R into KDVT
(Phoenix, Deer Valley), and VNAV guidance was provided on the external HSI in both cases. Interestingly,
these are traditional GPS approaches, not the newer ones with specific LPV or LNAV/VNAV minimums,
and VNAV was provided in both cases. In the Coolidge case, we took it all the way down, and it split the
runway laterally and the G/S pointer took the altitude right to the threshold. All this out in the middle of the
desert with no ground navaids. Very cool.

So, I'm confused by what's causing your restrictions. Could it be something specific to your F/D-A/P
setup? I don't have either one, so maybe the logic is restricted only if there's an autopilot. Or perhaps
WAAS updating was unavailable when you tried it. Is it restricted even when WAAS is known to be
working?

Mike

"Mike Adams" > wrote in message =
news:HxXBd.6305$232.4499@fed1read05...
> "John R. Copeland" > wrote:
>=20
>> As I've posted earlier, the glide-slope needle in my Flight Director
>> is not driven from the CNX80/GNS480 unless VNAV minima are published.
>> This defeats autopilot coupling to the computed glideslope on
>> non-precision approaches. However, the HSI display of the NAV page
>> shows vertical guidance for most LNAV approaches, as a welcome aid =
for
>> stabilized descents.=20
>>=20
>=20
> I just took delivery on my GNS480 upgrade, and in the initial test =
flight, did not see what you are=20
> experiencing. We flew the GPS23 approach into P08 (Coolidge, AZ), and =
the GPS07R into KDVT=20
> (Phoenix, Deer Valley), and VNAV guidance was provided on the external =
HSI in both cases. Interestingly,=20
> these are traditional GPS approaches, not the newer ones with specific =
LPV or LNAV/VNAV minimums,=20
> and VNAV was provided in both cases. In the Coolidge case, we took it =
all the way down, and it split the=20
> runway laterally and the G/S pointer took the altitude right to the =
threshold. All this out in the middle of the=20
> desert with no ground navaids. Very cool.=20
>=20
> So, I'm confused by what's causing your restrictions. Could it be =
something specific to your F/D-A/P=20
> setup? I don't have either one, so maybe the logic is restricted only =
if there's an autopilot. Or perhaps=20
> WAAS updating was unavailable when you tried it. Is it restricted even =
when WAAS is known to be=20
> working?
>=20
> Mike

That's intensely interesting, Mike. I haven't had WAAS unavailable.
But if it were unavailable, the CNX80 wouldn't show its computed
glideslope presentation on its internal NAV display, either.
Feedback I got from the Apollo tech rep through my avionics shop
said that it was an intentional restriction on driving the VDI needle,
intended to foil 3-axis autopilots from locking onto the vertical
guidance unless VNAV minima were published as part of the approach.

I don't know if the CNX80/GNS480 can be "aware" of whether the
airplane is equipped for 3-axis coupled approaches. Perhaps.
Since I had one of the very first upgrades to CNX80 version 2,
now I'll need to check to see if that VDI restriction was later =
relieved.
Indeed, I originally expected to see the VDI active in my flight =
director,
and that's why I questioned its behavior after my first test flight.
Thanks for those details, Mike.
If you hear anything more about this, please post.

Regarding "splitting the runway", I have an MX20 MFD also,
and it almost always depicts me closer to the centerline of a
runway than to either edge. It's amazing!

Greetings,
The autopilot limitations comes from the autopilot manfacturer, not the
GPS at this point. Apparently the TSOs for the GA autopilots were not
designed or flight tested for LNAV/VNAV and LPV approaches. I expect
these problems to be resolved in the near future so we can let 'George'
fly to minimums with the GPS and be able to snooze just a wee bit
longer.

Mike, two questions: Were either of those GPS approaches flown coupled?
What is the date and version of your GNS480 (or CNX80) software?
Fly SAFE!
Jedi Nein

On Sun, 02 Jan 2005 15:23:47 GMT, "John R. Copeland"
> wrote:

>WAAS/GPS altitude is used for VNAV approaches.
>It works very well, really.
>Baro-VNAV is beyond the scope of the CNX80/GNS480.

I wonder why that is, since my encoding altimeter interfaces with my CNX80.
So, if I enter the altimeter setting, I will get a fairly accurate altitude
readout (within 10-20' of my panel altimeter).

>
>As I've posted earlier, the glide-slope needle in my Flight Director
>is not driven from the CNX80/GNS480 unless VNAV minima are published.

Well, I just picked up my a/c with the upgraded CNX80. Due to time
constraints, I did not do anything other than fly home and execute the GPS
Rwy 15 approach at KEPM. In any event, this is an LNAV approach with only
LNAV minimums. However, it does have vertical guidance as evidenced by a
screened descent line; a vertical rate of descent/GS table; and also a TCH
at the rwy end MAP.

Although there are no VNAV minima published, I DID receive vertical
guidance on both the NAV page of the CNX80 as well as on the VDI of my
external NSD360 HSI. So, clearly, there was nothing in my CNX80 inhibiting
external VDI on this approach.

I don't understand why your FD doesn't receive vertical guidance on
approaches where it is provided.


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

Greetings,
I teach both the GNS 530 and 480, and have written several books on how
to use them. Even though the enhancements to the 480 have made it
somewhat easier to use and it currently offers precision GPS approach
capability, I still recommend the 530 over the 480.

When the fit hits the shan, the 530 is faster to use, has easier
button-press & knob-twist sequences, and generally seems more
intuitive. When I toss an emergency situation requiring a diversion to
an unplanned alternate to a pilot learning their GPS, those with 530s
are headed towards their new destination minutes faster than those with
CNX80s/480s.

>From my latest tour of Garmin, I fully expect to see the 530
WAAS/Precision GPS approach upgrade within the next year. Terrain
information should be out *shortly* (much more shortly than this time
last year).

I have a longer and more detailed comparison between the two units. As
soon as I find it and update it, I'll get it posted to the newsgroup.
Fly SAFE!
Jedi Nein

"Jedi Nein" > wrote in message
oups.com...
> Greetings,
> I teach both the GNS 530 and 480, and have written several books on how
> to use them. Even though the enhancements to the 480 have made it
> somewhat easier to use and it currently offers precision GPS approach
> capability, I still recommend the 530 over the 480.

What would you think of a 530 and a 480 combination? Any benefit?

MX20 vs. FlightMax EX5000?


--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO

Greetings,
A 530/480 combination loses the crossfill ability of a 530/430,
530/530, or 480/480 combo. You'll have to learn both units instead of
one unit. Other than that, you'll get the best and worst of Garmin in
one panel.

MX20 versus the EX5000 is no comparison. The Avidyne units talks to
more interfaces, is far more intuitive, and has a larger display. If
you meant the EX500, it too knocks the MX20 out of the air. My ideal
panel is dual 430s with an EX500(0), followed by the G1000.

As for the 430 versus the 480......

I never could find the copy of my old comparison, so here is a new one.
I am a Master CFI and an expert (per a bunch of folks including
Garmin) on the 530, 430, 480, G1000, and a bunch of other units. My
specialty is training these gee-whiz boxes. I can take someone who has
never used a computer before and have them successfully completing a
GPS approach by the third lesson.

Ok, 430 versus the 480:
480:
Has 13 fixed buttons and 9 changeable buttons. Depending on the mode
of the unit, the functions of those 9 buttons change. Of those buttons,
3 are dedicated to COMM/NAV/Transponder, leaving 10 fixed and 9
changeable to the GPS.
Slightly larger screen than the 430.
Has a discontinuity 'feature' making the unit think the pilot bought
this GPS to do anything BUT go GPS Direct.
Requires expanding the flight plan, making the change, then executing
any change made.
Has Airways. Big whoop. I almost never fly them, and when I do, I put
in two waypoints that define the route, either intersections or VORs,
and I have the airway.
Has WAAS. So it is down to 7 feet and not 14.
Allows for precision GPS Approaches. Cool. The 430 will have those by
the end of the year. Neither allow the autopilot to follow the
glideslope until the autopilot manufacturers catch up.
Doesn't require hitting SUSP while going missed approach. On the other
hand it always assumes you are going missed approach.
Has a HSI screen. Good for backup, but I use the external CDIs more
often.
Default go-directly-to-start button is MAP.
Multiple ways to do something, but only certain ways are available
depending on what page or mode the unit is in.
Frequency changes require stopping whatever GPS input was being made to
make the frequency change.
Four customizable map pages that require a lot of tweaking to be
usable.
Overlays include traffic. If you want more, buy an MX20.
Big Knob, Little Knob, Cursor On, Cursor Off, Press the button, what
mode, Execute the change lets you master this unit.


430:
Has 17 fixed buttons. They work the same way every time. Of those 17, 5
are dedicated to the COMM/VOR radio, leaving 12 for the GPS.
Slightly smaller screen than the 480.
Unit assumes you will go GPS direct when no other course method is
available.
If you change something in the active flight plan, you make the change.
Done.
Requires hitting SUSP while navigating on the missed approach, until
the WAAS upgrade.
Default go-directly-to-start button is CLR, hold for 3 seconds.
In an emergency, pilots have less buttons to hit to get the unit to
change its navigation than the 480. And that navigation change does not
dump the original flight plan.
Faster to learn and use. Pilots as a whole seem to catch on faster with
the 430, and use more of its features as compared to those I've trained
on their CNX80/480s.
While there are multiple ways to do something, those ways are
consistent no matter what mode the unit is in.
You can actively work the GPS and the COMM at the same time. The
co-pilot can put in the new course while the pilot puts in the new
frequency. Or you can be in the middle of a change to the GPS course,
stop, dial in the new frequency, and continue exactly where you left
off in the GPS.
One Map Page, highly customizable.
Overlays include traffic, weather, Stormscope, and so on.
Big Knob, Little Knob, Cursor On, Cursor Off lets you master this unit.

Overall, software version 2 was a big help to the CNX80/480. It can do
a couple of things the 430 currently can not do, but not for long. It
requires more button pressing and has a steeper learning curve than the
430. Software version 2 was slapping a bandage on a human factors
nightmare (no offense to my friends in Salem). I'm hoping Version 3
will make even more improvements.

Faced with deciding between the two, I recommend the 430 and save the
2K for the WAAS upgrade later this year.

But don't take my word for it. Download both simulators, get the
manuals, and start playing with the boxes. You can also get a copy of
my Inflight Quickref Guide (www.slantgolf.com), the 'Cliff's Notes' to
these units, and use the simulators or head into your local avionics
shop with the units on display. While the manufacturers manuals are
okay, mine just simply give you the button presses and knob twists to
do something. Either way, they allow you to find out for yourself which
unit is easier for YOU to use.

This is most important. Which unit is easier for you, the one that has
to use these? Your flight instructor probably knows one, maybe two, and
as their own preference they usually choose the one they learned first.


Do you need airways which require plugging in the starting point and
the exit point? Or can you plug in the starting point, the course
changes, and the exit point once, save the flight plan, and not have to
plug in the course changes again?

Do you happen to live at an airport with an LPV approach that is
actually to lower mins than the other approaches to the airport? Will
you actually fly down that low or are your personal mins much higher?
(BTW, we have an LPV approach available to us, about an hour away. Mins
are twice as high as the ILS and slightly higher than the GPS LNAV
approach.)

Do you want to deal with the "Microsoft"-like 'are you sure you really
want to go GPS direct with your GPS unit?' 'Ok, I'll let you go Direct,
but if you don't save your changes, I won't do it and won't tell you
why.'

It's your panel. Choose wisely.

Fly SAFE!
Jedi Nein

"Jedi Nein" > wrote in message =
ps.com...
>=20
> <Snipped: a large amount of correct information,
> and a little misinformation as well.>
>=20
> Fly SAFE!
> Jedi Nein
>

I'm really happy I didn't consult you before buying my CNX80 and MX20.
I'd never denigrate the 430/530 units, but I really prefer my CNX80.
TSO-C146 vs. TSO-C129 was a no-brainer choice for me,
and I was unwilling to wait for the (probably expensive) 430/530 =
upgrades.
And I certainly did compare the simulators before purchase, too.

For MFDs, however, I think the MX20 is better than the EX500.
If I'd been happy enough with the EX500, I wouldn't have had to
replace my radar to be able to control it through my MFD.
I've never been up close to an EX5000, though, so I don't know about it.
Its specifications read pretty well.

Your advice to choose what one likes best is certainly apt.
It's much more apt than adopting anyone else's prejudices.
My own prejudices are bad enough. :-[

Greetings,
Your *snip* suggests I gave incorrect information. Would you be so kind
as to enlighten me on any incorrect information I gave out? Or is that
your standard *snip*?

Thanks!
Jedi Nein

On Mon, 17 Jan 2005 21:38:17 GMT, "John R. Copeland"
> wrote:

>"Jedi Nein" > wrote in message ps.com...
>>
>> <Snipped: a large amount of correct information,
>> and a little misinformation as well.>
>>
>> Fly SAFE!
>> Jedi Nein
>>
>
>I'm really happy I didn't consult you before buying my CNX80 and MX20.
>I'd never denigrate the 430/530 units, but I really prefer my CNX80.
>TSO-C146 vs. TSO-C129 was a no-brainer choice for me,
>and I was unwilling to wait for the (probably expensive) 430/530 upgrades.
>And I certainly did compare the simulators before purchase, too.
>
>For MFDs, however, I think the MX20 is better than the EX500.
>If I'd been happy enough with the EX500, I wouldn't have had to
>replace my radar to be able to control it through my MFD.
>I've never been up close to an EX5000, though, so I don't know about it.
>Its specifications read pretty well.
>
>Your advice to choose what one likes best is certainly apt.
>It's much more apt than adopting anyone else's prejudices.
>My own prejudices are bad enough. :-[

John,

Did you see my note regarding that my external HSI works with my CNX80 even
without published VNAV minima, so long as there is advisory vertical
guidance being generated?

I believe you wrote that was not the case with your setup and FD.
Obviously, there is something other than the absence of VNAV minima to
cause this behavior in your system.


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

"Ron Rosenfeld" > wrote in message =
...
>=20
> John,
>=20
> Did you see my note regarding that my external HSI works with my CNX80 =
even
> without published VNAV minima, so long as there is advisory vertical
> guidance being generated?
>=20
> I believe you wrote that was not the case with your setup and FD.
> Obviously, there is something other than the absence of VNAV minima to
> cause this behavior in your system.
>=20
>=20
> Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Ron, I did see your note, after I returned from a Florida trip,
and I'm attempting to find out why my installation behaves differently.
I received a phone call today direct from Salem, and learned that
there has been no change of software since my upgrade,
so that possibility is ruled out.

The representative attempted to put me in touch with another person =
there
to discuss my specific equipment, but he was unable to do more than
leave a voicemail message with the other party.
He said they would be back in touch with me later.
Just incidentally, he said in passing that they themselves were =
surprised
to learn so many thousands of GPS approaches had vertical guidance =
available.

My representative is convinced we'll be able to learn why my system
behaves as it does, and actually correct it if a correction is needed.
Thanks for starting that ball rolling for me, Ron.

"Jedi Nein" > wrote in message =
oups.com...
> Greetings,
> Your *snip* suggests I gave incorrect information. Would you be so =
kind
> as to enlighten me on any incorrect information I gave out? Or is that
> your standard *snip*?
>=20
> Thanks!
> Jedi Nein
>
No, that was a customized *snip*.
I didn't want to pick nits about your comparison, but since you asked...

You seemed to involve the 480's discontinuity 'feature' in going direct.
The discontinuity is part of an incomplete flight plan,
and is not involved with navigating "direct-to" a selected location.

You said you can put in two points to "define the route",
and thus "have the airway".
However, few airways go very far along a single great-circle path.
With the 480, you don't need to enter intervening airway inflection =
points.
I agree with you about almost never flying airways, but our friends
in the northeast U.S. seem to be constrained to airways frequently.

You said neither the 480 nor the 430 allow the autopilot to follow the
glideslope until the autopilot manufacturers catch up.
I don't know what that "catch up" would be, because my own
30-year-old, three-axis autopilot flies the VNAV approaches quite well,
including arming and capturing the glideslope, exactly as it does ILS.

You said the 480 always assumes you are going missed approach.
The 480 does not assume you are flying a missed approach if you
land and decelerate on the rollout.
When I do a missed approach, the 480 gives me guidance automatically,
after I climb the requisite amount to begin the missed approach.

I actually didn't understand what you meant by
"Default go-directly-to-start button is MAP",
so I'm unsure if that was a complete statement or not.

I don't mean any of the above to detract from the 430/480 comparison
you posted, and it's always good to see opinions such as yours in the =
open.

On Tue, 18 Jan 2005 01:15:21 GMT, "John R. Copeland"
> wrote:

>Just incidentally, he said in passing that they themselves were surprised
>to learn so many thousands of GPS approaches had vertical guidance available.

And flying my first one with vertical guidance, KEPM GPS Rwy 15, which I
have flown without vertical guidance many times, I must admit that
following the GS and doing a constant rate of descent made for a much
smoother and easier to fly approach than did my usual "dive and drive"
method. Of course, I need to refine this for use at IFR minimums, as the
procedure is somewhat different since the GP intersects MDA at more than
the visibility minimums distance from the airport (and the MAP is at the
runway threshold).

Using MDA as a DA (if it were legal) would deprive me of being able to land
with visibility at minimums; so it's a matter of levelling off at MDA and
"driving" for a while before executing the miss. Sort of a cross between
an ILS and a "dive & drive" approach.


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