Arne wrote:
What’s wrong with the 430?
Oh, I wrote that a long time ago and I really don’t remember what I was thinking. Your question is a good one. Keeping it would indeed give some kind of RNAV redundancy, depending on whether the (additional) database would be kept updated.
The only reason to take it out would be to get a couple of kEUR to spend on new stuff – but it is probably worth more to us installed.
huv wrote:
now we are looking at getting rid of both the 430 and the KX155
What’s wrong with the 430?
The G5 is a fully digital unit with no analog signal processing – so therefore unfortunetly no connectivity for the old Nav Coms
Sir_Percy wrote:
G5 itself is capable of handling two NAV sources
@Sir_Percy, that could be of interest for us. But would it accept that one of the sources be from an old unit like the KX155?
The G5 itself is capable of handling two NAV sources. Garmin recently announced that it would be legal in a certified installation soon.
Electrically they can be connected via RS232 or A429 via the GAD29B. Concerning the autopilot it depends on your AP and how it is wired to the NAV receivers. It doesn‘t necessarily have to be dependent on the G5.
Airborne_Again wrote:
I don’t see why it would be illegal?
I cannot find it either. And the ILS indicator in question have indeed worked so far when flying ILS approaches, so I guess you are right.
Airborne_Again wrote:
are you planning to use a relay to switch the connection to the G5
Yes. I know from another G5 installation that the shop disconnected the old NAV1/NAV2 switch for the autopilot because that would only work with two digital Garmin units, they said.
But it we go for the GTN 650 instead, it would become a non-issue, with automatic/semiautomatic CDI changeover from GPS to ILS.
huv wrote:
But worst of all, it seems that the G5 HSI will not be able to show ILS guidance from an old unit, if coupled to the 355. That would mean flying an ILS looking at the old ILS clock to the side while the G5 HSI right in front of you would indicate something else. Probably not legal and probably for a good reason.
I agree it would not be a good idea as you lose a major reason for having a HSI in the first place and also can’t run the A/P from the ILS, but I don’t see why it would be illegal? Lots of light aircraft have the #1 NAV on a HSI and the #2 nav on a CDI. That doesn’t prevent you from flying an ILS tuned to the #2 NAV.
So, now we are looking at getting rid of both the 430 and the KX155 and replace them with a GNC355 and a GNC255 NAVCOM, because that would allow both the G5 HSI and the autopilot to run on both units. However, then we could just as well go for the GTN650, pricewise.
I’ve looked at the G5 IM and I don’t see how you can connect two units to a G5 HSI, even if each unit can be connected separately. Or are you planning to use a relay to switch the connection to the G5?
My syndicate is specifically considering the GNC355. We have an old Garmin 430 and an even older KX155, both with ILS. We could remove one of those, install the 355 as NAVCOM #1 and still have ILS capability and a COM2 (although only one 833, if we ditch the 430).
If we do that, we will have the capability we need, and save $5k+ compared to the GTN650 we thought that we were going to have.
We quickly realised that with the 355, we would have to switch nav unit when going from GPS-navigation to flying the ILS at the end of the IFR flight.
We are also told by our shop that with the 2 x G5 (attitude & HSI) that we also plan to install, the autopilot will not be able to run on more than one unit (no NAV1/NAV2 switch). That would mean having the autopilot for the 355 (all en-route flying and PBN approaches) and not being able to fly an ILS on autopilot.
But worst of all, it seems that the G5 HSI will not be able to show ILS guidance from an old unit, if coupled to the 355. That would mean flying an ILS looking at the old ILS clock to the side while the G5 HSI right in front of you would indicate something else. Probably not legal and probably for a good reason.
So, now we are looking at getting rid of both the 430 and the KX155 and replace them with a GNC355 and a GNC255 NAVCOM, because that would allow both the G5 HSI and the autopilot to run on both units. However, then we could just as well go for the GTN650, pricewise.
Airborne_Again.
Business is not about making sense, it is about making Money.
Peter wrote:
It’s all a part of a strategy called product differentiation and everybody does it
Sure. My favourite story comes from a guy in my club who was manager of cabin systems at Scandinavian Airlines (this was in the 1980s). As old enough people will remember, in-flight entertainment in Economy Class at that time did not use proper headphones. Instead there were speakers in the armrests which were connected to headphone-like things by plastic tubes. Of course Business Class had proper electric headphones.
Now, this guy told me that it was actually more expensive to do it this way than it would be if economy class also had proper headphones. But it was important for product differentiation between the two ticket classes.
So the airline actually took additional costs to make service in Economy Class worse!
