R9 - GPS Problems

Unfortunately it looks like the antenna was not the issue after all. Ian Kirby from Complete Avionics at the Gold Coast in Australia is going to contact your tech guys Monday your time to see if they can come up with anything.

Below is the email I sent to ian this morning for his discussion with Avidyne and outlines the history of the problem.

Would appreciate if you could follow up with the tech support guys to make sure they respond as quickly as possible. I am kind of stuck with local VFR flights only at the moment while this problem persists. It i super frustrating.  

Regards

Andrew

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Ian, 

As discussed here is the history of VH WWJ's current GPS issue. 

1. About 6 months ago I started getting intermittent GPS 1 failures in flight. The failure frequency was a failure every 3 or 4 flights.

2. The failures gradually became more frequent and I realised if I rebooted IFD1 in flight the situation would resolve. 

3. Over the last few weeks, GPS1 failures became more frequent (sometimes several times in a flight) and GPS2 often also started going offline once GPS1 had failed, resulting in dual GPS failures and having to reboot both IFD's to get the GPS's back online. 

4. Once while on the ground, I noted on the sensor page that the HPL and VPL figures for GPS1 were rapidly increasing before the GPS went to fault mode. Other times while I have been watching they have gone from solid reception straight to fault mode.

5. As you know we replaced the antenna for GPS1, but it appears we did not resolve the issue.

 

Moving GPS#2 to an external antenna is unlikely to remedy the problem. GPS#1 already has an external antenna and is the one that was failing initially, triggering this whole issue. Both the external antenna GPS and the internal antenna GPS simulatneously went from good reception to Failure mode with no preceding warnings or loss of integrity. One minute they were just fine and then "bang", both in Failure mode. 

Regards

Andrew