GNC-300XL IFR GPS/COM

Anyone have any experience with the GNC-300XL IFR GPS/COM?

Does it work well? Do you like the user interface? How is the
screen?

I want to have GPS IFR capability in my 172. What else will I have to
install to get IFR cert for this unit?

Thanks,

Jeff

I've been flying one for over 4 years. Works fine for IFR and VFR but it's
all I know. I only have 2-3 hours behind a 430.

Given a good price, I would think this is a good choice for a personally
owned a/c. The screen is great. The installation will require a CDI head
that you will probably share with your NAV. That sharing will require a
switch/annuciator panel. Definitely have it installed by someone who has
done IFR installations with them before. No need to pay for a learning
curve this late in the box's life.

Has operated flawlessly so far.

"Jeff P" wrote in message
om...
Anyone have any experience with the GNC-300XL IFR GPS/COM?

Does it work well? Do you like the user interface? How is the
screen?

I want to have GPS IFR capability in my 172. What else will I have to
install to get IFR cert for this unit?

Thanks,

Jeff

The 300XL, is kind of first and a half generation GPS. The 155 was first,
and Garmin had trouble with the unit due to the eight channel receiver.

The 155XL and 300XL got the newer and better 12 cannel receiver along with a
crude moving map. Several other user friendly features were added. The XLs
self armed and the BARO was no longer required to be input from the pilot.

The logic in the 155XL/300XL is as good as the first generation units get,
but much worse than the later units like the 430.

All the panel mount IFR units require an external CDI, except the CNX80. The
155/300XL commonly used the MD-41, which makes the system completely "stand
alone." Part of the added expense of the XL series is the requirement for
external switching. You will need two if you have a dedicated CDI, and three
if sharing a CDI, like the King 109A.

Because of the added expense of the switches and installation you might be
better off to just buy a 430 on eBay for around $6000. You would have a much
better map and logic. The 300XL will cost $2500 and the extra switching will
cost at least $500. So you'd be looking at an extra $3000. Pretty soon the
first generation units will be almost worthless, just like the original
GPS155.

Karl

Jeff,

I'm about to get this unit installed into my PA28-140. To be legal for IFR
approaches, you'll need (as others have said):

- An external CDI. I happen to be using the GI-106 (more on that
below).
- An external annunciator/switch which: a) lets you share the head
between the GPS and a NAV radio; b) gives you course deviation while flying
an approach; and c) tells you when the approach is active and armed.
- A flight manual suplement. Your avionics tech should be providing
this as part of the install. If not, then you're not legal.

You'll also need to keep your GPS database up to date (unless you're not
using it for approaches then, technically, you can fly with an out of date
DB). Jeppesen charges around $300 for a year of updates. As one poster
mentioned, you can use an MD-41 (MidContinent?) which combines the CDI and
annunciator into one unit. That'll save you some bucks. With a 430 you
only need the CDI, the annunciator is built into the box. One last,
probably inconsequential note: the 300XL isn't certified for WAAS approaches
and probably never will be. Neither is the 430 although Garmin says they
plan to add it "soon".

I'm replacing a crusty old NAV/COMM/CDI and an ADF which means either the
300XL or the 430 (i.e. a pure GPS unit like a KLN90 would leave me with only
one COMM).. Many of the used 430s are 28v units which my avionics guru
advised me against (apparently, the voltage converter needed to step down to
14v is not terribly reliable). Compared to a new 430, a cheaper overhauled
300XL is an acceptable tradeoff for my steed. My second NAV/COMM only had
the localizer head, so I opted for the GI-106 which will give me a
glideslope needle when I need it.

You can get an overhauled 300XL on ebay for about $2400. A company called
JA Incorporated periodically buys up all the overhauled Garmin units so they
almost always have them in stock. If you want to skip ebay, go to
avionicsgps.com, where they advertise the 300XL for $2600.

Best of luck....

mark

"Jeff P" wrote in message
om...
Anyone have any experience with the GNC-300XL IFR GPS/COM?

Does it work well? Do you like the user interface? How is the
screen?

I want to have GPS IFR capability in my 172. What else will I have to
install to get IFR cert for this unit?

Thanks,

Jeff

I installed this unit as the number two in my previous plane (number one was
a kx-155 w/GS). I thought it was a great budget unit. $2400 on ebay from
JA Air. All in including certification I was out $6800. Having now flown
behind a pair of 430's for 25 hours, I still think that the set up above was
perfect for a 79 Grumman.

"Jeff P" wrote in message
om...
Anyone have any experience with the GNC-300XL IFR GPS/COM?

Does it work well? Do you like the user interface? How is the
screen?

I want to have GPS IFR capability in my 172. What else will I have to
install to get IFR cert for this unit?

Thanks,

Jeff

So maybe I'm missing something and hope someone can explain it to me.
If you need an indicator for an IFR box, why not a dedicated
indicator? One with the warn lights, etc., that would not be shared?
Wouldn't that eliminate the need for a switching device? Which ones
would qualify? KI209A, etc.?

On Wed, 15 Oct 2003 05:39:24 GMT, "Flynn"
wrote:

I installed this unit as the number two in my previous plane (number one was
a kx-155 w/GS). I thought it was a great budget unit. $2400 on ebay from
JA Air. All in including certification I was out $6800. Having now flown
behind a pair of 430's for 25 hours, I still think that the set up above was
perfect for a 79 Grumman.

"Jeff P" wrote in message
. com...
Anyone have any experience with the GNC-300XL IFR GPS/COM?

Does it work well? Do you like the user interface? How is the
screen?

I want to have GPS IFR capability in my 172. What else will I have to
install to get IFR cert for this unit?

Thanks,

Jeff

"Stu Gotts" wrote:
So maybe I'm missing something and hope someone can
explain it to me. If you need an indicator for an IFR box,
why not a dedicated indicator? One with the warn lights,
etc., that would not be shared? Wouldn't that eliminate the
need for a switching device?

That's the setup in my airplane. There are two CDI's for the Cessna nav/coms
one for the GPS plus a GPS annunciator. The only switch involved is one that
selects which CDI the autopilot is using.
--
Dan
C172RG at BFM

If you need an indicator for an IFR box, why not a dedicated
indicator? One with the warn lights, etc., that would not be shared?


That would be the MD-41.

You will still need two switches. Arm/disarm and Hold.

The dedicated system is the way to go. Then you can still use the VHF Nav
simultaneously.

Karl

My thought is that perhaps adding a suitable HSI (I'd love to put in a
Sandel) at the same time as the GPS would give you a GPS indicator without
having to do anything with the existing nav heads. I currently have a
KX155/KI209 for my #1 and A nav122 plus an MX11 comm for #2. When the time
comes, my current plan is to replace the MX11 with a GPS/comm and the DG with
an EHSI. Seems I could get the EHSI plus an older GPS-comm for a little more
than a 430 with indicator alone.

karl gruber wrote:

If you need an indicator for an IFR box, why not a dedicated
indicator? One with the warn lights, etc., that would not be shared?

That would be the MD-41.

You will still need two switches. Arm/disarm and Hold.

The dedicated system is the way to go. Then you can still use the VHF Nav
simultaneously.

Karl

--
--Ray Andraka, P.E.
President, the Andraka Consulting Group, Inc.
401/884-7930 Fax 401/884-7950
email
http://www.andraka.com

"They that give up essential liberty to obtain a little
temporary safety deserve neither liberty nor safety."
-Benjamin Franklin, 1759

Well in my particular case, the radio I'm replacing is a narco with a narco
glideslope head that won't work with my other nav/comm (a KX-175B). So I'd
have to buy two heads if I wanted to fly a precision approach: one for the
new GPS, and one with a glideslope needle (I DO have a KI201C currently on
my KX-175B but, even if that would work for the GPS, I'd still need to buy
the annunciator, etc). I opted to buy just one head with a glideslope
needle and share it between the GPS and my nav/comm. En route, I certainly
wouldn't be using both at the same time, and I couldn't think of any
approach situations where I'd need a CDI for both. If you're not in this
particular situation then yes, it makes better sense to buy the MD-41
combination.

mark

"Stu Gotts" wrote in message
...
So maybe I'm missing something and hope someone can explain it to me.
If you need an indicator for an IFR box, why not a dedicated
indicator? One with the warn lights, etc., that would not be shared?
Wouldn't that eliminate the need for a switching device? Which ones
would qualify? KI209A, etc.?

On Wed, 15 Oct 2003 05:39:24 GMT, "Flynn"
wrote:

I installed this unit as the number two in my previous plane (number one
was
a kx-155 w/GS). I thought it was a great budget unit. $2400 on ebay
from
JA Air. All in including certification I was out $6800. Having now
flown
behind a pair of 430's for 25 hours, I still think that the set up above
was
perfect for a 79 Grumman.

"Jeff P" wrote in message
. com...
Anyone have any experience with the GNC-300XL IFR GPS/COM?

Does it work well? Do you like the user interface? How is the
screen?

I want to have GPS IFR capability in my 172. What else will I have to
install to get IFR cert for this unit?

Thanks,

Jeff