Should I install dual GPS-2020s?

[MN_Flyer]

Finishing the planning of my dual HDX panel and trying to understand system redundancy and failure modes. If wiring a SV-GPS-2020 per the installation manual, the unit is powered via spliced voltage and spliced serial data from both HDX displays. I am sure the thinking is that a a failure of one display would not cause the GPS to lose power, but wondering about a dead short in one display or junk serial data from one HDX display corrupting the other.

Any thoughts on this? My installer recommends dual GPS units, but I am honestly not sure how necessary another $600 receiver is for a plane that also has a G5 and GTN650 for backups.

I am installing dual ADAHRS and a backup battery for the avionics power bus for IFR flight. Any other recommendations? Thanks in advance for any thoughts,
Dan

 

[DBRV10]

Probably would not bother me at all. VFR machines can get by quite happily with one SV-GPS, and lets face it, you have a smart phone or iPad too should the highly unlikely happen.

I would also say with some reasonable experience, the GPS is the most reliable part of the system.

 

[Raymo]

I installed the older GPS-250 and the 2020 only because I already owned both. Down-side is that the 250 uses a serial input that I may need for something else down the road. When that happens, the 250 will go away and likely have an IFR navigator takes its place.

 

[kellym]

Finishing the planning of my dual HDX panel and trying to understand system redundancy and failure modes. If wiring a SV-GPS-2020 per the installation manual, the unit is powered via spliced voltage and spliced serial data from both HDX displays. I am sure the thinking is that a a failure of one display would not cause the GPS to lose power, but wondering about a dead short in one display or junk serial data from one HDX display corrupting the other.

Any thoughts on this? My installer recommends dual GPS units, but I am honestly not sure how necessary another $600 receiver is for a plane that also has a G5 and GTN650 for backups.

I am installing dual ADAHRS and a backup battery for the avionics power bus for IFR flight. Any other recommendations? Thanks in advance for any thoughts,
Dan

Totally unnecessary. Your GTN 650 can be wired as the ADS-B position source, with the GPS-2020 as a backup position source, if you want. Why in the world would they be trying to talk you into triple redundancy? Over thinking failure possibilities. I have dual Classic screens with dual ADAHRS, with GTN-650 as the legal ADS-B position source. Uses GPS-250 to drive the screens. Has been working fine for 4 years.