Garmin GPS 175 vs Skyview ARINC

[riseric]

This is also posted on the Dynon forum since a few days but no replies.
So here goes a shot in the dark:

I'm considering installing a GPS 175 connected through ARINC to Skyview which seems simple enough.
What about connecting a second GPS 175? (for redundancy, ie: Canadian IFR equipment regs)
Can it be connected to the same ARINC using the RX 2 A/B pins 22 & 10 and TX A/B pins 24 & 12 ?
What about the serial TX to RX pin 3, unneeded for the second unit or could/should it be connected in parallel?
Or a second ARINC is needed ?

 

[BobTurner]

1. I’m not Canadian, but IIRC the Canadian redundancy rules for ifr required different types of nav aids, e.g., two gps boxes don’t count (??)
2. The usual rule for both arinc and rs232 is:
One ‘out’ (or transmit) port can be connected to several ‘in’ (receive) ports, but the opposite is not allowed, e.g. one ‘in’ port cannot be connected to multiple ‘out’ ports.

 

[N890GF]

Can it be connected to the same ARINC using the RX 2 A/B pins 22 & 10 and TX A/B pins 24 & 12 ?
What about the serial TX to RX pin 3, unneeded for the second unit or could/should it be connected in parallel?

I think based on the Dynon documentation here and here (page 321 - section 12), it looks like you can connect two independent devices (a GPS/Nav for example), but nothing precludes you from connecting two GPS's it would seem. I also am not Canadian, so will not comment on any legalities associated with the installation.

 

[Flying Canuck]

1. I’m not Canadian, but IIRC the Canadian redundancy rules for ifr required different types of nav aids, e.g., two gps boxes don’t count (??)
2. The usual rule for both arinc and rs232 is:
One ‘out’ (or transmit) port can be connected to several ‘in’ (receive) ports, but the opposite is not allowed, e.g. one ‘in’ port cannot be connected to multiple ‘out’ ports.

I am Canadian. The two radio navigation sources could both be GPS provided they are fully independent. Definitely separate antennas and, depending on the individual inspector's interpretation, separate ARINC units. The requirement is

(j) sufficient radio navigation equipment to permit the pilot, in the event of the failure at any stage of the flight of any item of that equipment, including any associated flight instrument display,

(i) to proceed to the destination aerodrome or proceed to another aerodrome that is suitable for landing, and

(ii) where the aircraft is operated in IMC, to complete an instrument approach and, if necessary, conduct a missed approach procedure.

 

[riseric]

depending on the individual inspector's interpretation, separate ARINC units.

Thanks Claude,
I didn't think about mitigating a possible ARINC or its connections failure.
Double and independant everything it will be.

I weighed the option of installing a VHF antenna to a NAV receiver instead of a second GPS.
In my view, considering how many VOR were decommisionned lately and it will continue, (we lost at least 3 here in a 150 NM radius, YMX, VLV, YSC) and more and more airports are losing their ILS/LOC approaches to RNAV, (we have one here, CYRI, where a VOR is on site, but now only have RNAV approaches...) good luck navigating VHF and finding an airport that offers a VHF approach.
Remember that we don't have as high density airports per area as in the US, the nearest airport having a VHF approach can be more than a hundred miles away...
Yeah, a major solar flare or other catastrophy knocking out most GPS satellites while flying IMC will be problematic...
I will carry my portable VHF NAV/COM just in case...

 

[Flying Canuck]

Thanks Claude,
I didn't think about mitigating a possible ARINC or its connections failure.
Double and independant everything it will be.

It would be worthwhile to talk to your neighborhood TC inspector to see if they need that. I'm not sure the HDX can handle 2 SV-ARINC-429 units.

When I got the VFR only restriction lifted it was done after a lot of conversation with my local inspector. Made the process so much easier.

I did go with VOR/ILS as my second method, yeah it's getting less common but ILS is still the only precision approach available. It's also a lot cheaper than equipping with another GPS navigator.

 

[riseric]

Yes, HDX can handle 2 ARINC.
I will get in touch with TC (or is it MDRA?) for further info.

 

[Canadian_JOY]

For clarity...

MD-RA is responsible for issuing the initial Special Certificate of Airworthiness - Amateur-Built.

Modifications to the aircraft after the issuance of the initial SCofA are the responsibility of Transport Canada. This includes lifting the limitations imposed for the first 25 hours of operation including the Day - VFR Only limitation.

 

[Flying Canuck]

Yes, HDX can handle 2 ARINC.
I will get in touch with TC (or is it MDRA?) for further info.

As mentioned by Canadian Joy, it is TC in this case. I actually reached out directly to the inspector who did the paperwork at the end of my 25 hour test period.

Not sure if you saw this or not, but I documented my journey to lift the VFR Only limitation here

 

[riseric]

TC it will be.
And yes, I did see your thread and bookmarked it,
Thanks Claude