Ok it's clear to me that I'm going to connect some items to some screens via HSDB. But for anything with only one HSDB connection to one screen, that screen becomes a single point of failure.
Does it make sense to also wire CAN bus to my transponder and radio as a backup to the HSDB connections? Will the CAN bus allow communication to the remaining display if the display with the HSDB connection is down?
This really depends on the specific combination of equipment you are installing.
For any system with a single IFR navigator, you have a single point of failure for IFR GPS/NAV. Many will opt for the addition of a secondary source of navigation in the form of another AXIS display or external navigator.
Transponders do not connect to the system via CAN. You are able to connect them via RS-232 to the GSU 25, which has always been a single connection for that data. If you have a second GDU 25 in an AXIS system, you can actually create a second connection for this path.
The failure of an HSDB/CAN connection to a panel mount GTR 205 only has the effect of eliminating the remote control of the radio from the AXIS display. For Remote Mount GTR's, the radio is placed into a failsafe mode allowing you to continue using the radio, in the absence of the display head for the unit. Of course with no control over the active frequency of that radio.
Correct, but a couple things (if I'm understanding correctly, big if). To get full redundant G5 functionality still requires the ARINC interface. While the backup batter is nice, that is easily handled with an IBBS or two. I'm sure we will get answers soon. The idea of a three panel setup is appealing, but only if it has a reasonable level of backup.
Others have followed on with good comments on this topic, and we strongly recommend a standby flight display for aircraft to be flown into IMC. With a built in ADAHRS, different in both software and hardware, from the primary ADAHRS that drives your AXIS Primary Flight Display, you reduce the likelihood that you would find yourself with out your instruments. The backup battery strapped directly to the unit also reduces the unit's reliance on the main electrical system of the aircraft and eliminates some faults that can happen with that system.
There are a lot of permutations of AXIS system architecture, given the various generations of equipment the AXIS display can support. Whether a GAD 29 is required/suggested depends on the equipment present in the rest of the system. In most cases, wiring ARINC 429 from an external navigator through a GAD 29 (or GSU 73) is beneficial from a system redundancy standpoint.
I have a two G3X Touch 8"portrait displays with a GSU73, and a GMU44. If I upgrade the two screens to the new Axis 8" portrait screens, other than the faster processor, upgraded graphics (eye candy) etc., am I gaining any additional "functions" that I don't already have?
Thanks,
Christer
Top of mind, Runway Occupancy Awareness is one really great safety feature that comes along with AXIS. The ability to modify the flight plan of a cross-side IFR Navigator is a really great improvement as well. I think you would take great interest in the Logic Signal Editor that is baked into AXIS configuration mode as well. We will continue to add capability to that function over time, which is very powerful out of the gate. The new platform and display of course unlock a long future of development that was otherwise not feasible in previous generations of hardware.
I’m no expert on this but my understanding of the system architecture is that with the NC version you have effectively separate LRUs in one box, and each LRU has an independent power supply.
So with 2 screens, one NC and one BX, if the screen on the NC fails the other LRUs in the NC box will be available on the BX. So the NAV/COM functions should still be available.
Can someone correct me if I’m wrong, because this is the set-up I’m hoping to run.
If the NAV/COM/AUDIO board fails, your AXIS GPS board is capable of continuing to operate.
If the Main board fails, but the NAV/COM/AUDIO board is still operating, Audio and COM revert to a fail safe state and continue to operate with no access to the active frequency of the COM radio. You would lose NAV and GPS. For any system with a single IFR navigator, you have a single point of failure for IFR GPS/NAV. Many will opt for the addition of a secondary source of navigation in the form of another AXIS display or external navigator.
Regarding reliability, seems like 2 Bx screens and a GTNxi (650 or 750) are better than one NC and one Bx as it eliminates the NC as a single point com/nav failure. Am I missing something?
In both combinations of equipment, the single IFR GPS/NAV in the system is a single point failure.
In both systems described, if the IFR GPS fails, VFR GPS remains on the at least one of the two AXIS displays.
In neither of the systems described do you retain IFR GPS, in the case of a IFR GPS source failure.
In the first example, you would retain IFR GPS in the case that PFD1 failed, which is not true for the second example in which would fail down to VFR GPS. A second external navigator (GNC 215 NAV/COM or GNX 375 GPS/XPDR for example) or GDU 116C would protect you against the single point failure inherent to having only 1 IFR Navigator in the aircraft.
Given the particularly strong admonitions to save/record your G3X fuel calibrations, is there a method for installing them by download, (for four tanks it's a bunch of data/info - numbers, colors, etc.) or will they also need to be manually typed in like apparently all other settings and configurations?
Yes, fuel calibration files written from a G3X Touch system can be directly imported to the AXIS system.
At this time, the rest of configuratoin must be entered manually.
G3Xpert,
There is a disparity between the Installation Manual and Garmin's current software version for the G5. In preparing the AXIS upgrade from the G3X in Appendix F, the instructions are quite clear about ensuring all installed LRUs are loaded with their most recent software versions; otherwise, the AXIS system will not be able to interface correctly. For the G5, the minimum software version should be v8.70:
However, Garmin's most recent version is only v8.60:
Is another release coming soon? Thanks for reconciling this discrepancy.
We are in the process of releasing these software versions this week.
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