Losing GPS on approach
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- 2 Diamonds Member
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- First Name: Brian
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Losing GPS on approach
Has anyone experienced a loss of GPS in a DA62? I have been flying in a newly delivered plane and we have lost GPS several times while on approach (with approach loaded and activated). It always happens at around 2500 feet and clears itself up in about 40-70 seconds. We have just started to try to track it down and can't even tell if it is hardware or software related. One suggestion is to wipe out the G1000 NXi software and reinstall. This sounds like a bit of a pain considering they have pretty low confidence that it will help. Any ideas?
Thanks,
Brian
Thanks,
Brian
- Deanrobert
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Re: Losing GPS on approach
We had it happen in our 2017 da-62 , intermittently , when communicating on a frequency range between 121.0 and 121.3
Very strange. We had avionics shop check it out; thought the com antennas were two close ; all kinds of thoughts. It went away after our three year bonding check at annual. I was annoyed at the cost of checking all these grounding connections , but our gps approach issue kicking out stopped. So my take away is it has something to do with adequate , consistent grounding of the airplane…
Very strange. We had avionics shop check it out; thought the com antennas were two close ; all kinds of thoughts. It went away after our three year bonding check at annual. I was annoyed at the cost of checking all these grounding connections , but our gps approach issue kicking out stopped. So my take away is it has something to do with adequate , consistent grounding of the airplane…
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Re: Losing GPS on approach
Interesting, KEMT tower is 121.2. That is where we usually experience it.
- mfdutra
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Re: Losing GPS on approach
I had this problem on my 2023 DA62. Diamond replaced the GPS-1 antenna and the problem was solved. Maybe it’s bad batch. I have the serial 53 from Canada.
- MarkA
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Re: Losing GPS on approach
Brian,
This sounds similar to a problem I and several other DA40 owners had earlier. You might want to check out the thread below where an intermittent hardware failure in one of the GPS antennas caused enough RF interference to block out the other antenna as well. The symptom was that the G1000 would intermittently loose contact with all satellites. The two GPS antennas sit right next to each other above the pilot's head on a DA40.
viewtopic.php?t=8252
Once the failing antenna was identified, the test to confirm that this was the issue was pull the circuit breaker on the GIA63 that was connected to the bad antenna and observe the satellites connecting through the good antenna. I've not seen any issues since the bad antenna was replaced.
This sounds similar to a problem I and several other DA40 owners had earlier. You might want to check out the thread below where an intermittent hardware failure in one of the GPS antennas caused enough RF interference to block out the other antenna as well. The symptom was that the G1000 would intermittently loose contact with all satellites. The two GPS antennas sit right next to each other above the pilot's head on a DA40.
viewtopic.php?t=8252
Once the failing antenna was identified, the test to confirm that this was the issue was pull the circuit breaker on the GIA63 that was connected to the bad antenna and observe the satellites connecting through the good antenna. I've not seen any issues since the bad antenna was replaced.
2010 DA40 XLS, N123MZ, KHIO
https://youtu.be/LuQr6mGxffg
https://youtu.be/LuQr6mGxffg
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Re: Losing GPS on approach
Thank you Marlon and Mark,
These are super helpful for troubleshooting. It has been so intermittent that we can't get it to repeat on demand. These will give us some steps to try first. I will report back when we get to the bottom of it.
Brian
These are super helpful for troubleshooting. It has been so intermittent that we can't get it to repeat on demand. These will give us some steps to try first. I will report back when we get to the bottom of it.
Brian
- haykinson
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Re: Losing GPS on approach
Does it always happen in the same area? There are, for example, GPS anomalies that happen in the vicinity of KSMO — for years, I've lost ADS-B coverage due to a loss of GPS at around 1300 AGL, and even had full GPS loss during an approach (fortunately in visual conditions). The airport even had gone through a few weeks of having ATIS declare that GPS is unreliable after the latest bout of issues.
- MarkA
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Re: Losing GPS on approach
Note also that if the problem is caused by an intermittent failure of one of the GPS antennas, even when the antenna fails there's no indication of a hardware problem in the low-level G1000 error logs. The G1000 just thinks it lost contact with the satellites for some reason.
When diagnosing my issue, I did noticed the GPS signal strength reported on the G1000 AUX page for the intermittently failing antenna was consistently weaker than the good antenna. The failing antenna also reliably took longer to initially acquire the satellites. These are just hints for which antenna may be causing the problem.
When diagnosing my issue, I did noticed the GPS signal strength reported on the G1000 AUX page for the intermittently failing antenna was consistently weaker than the good antenna. The failing antenna also reliably took longer to initially acquire the satellites. These are just hints for which antenna may be causing the problem.
2010 DA40 XLS, N123MZ, KHIO
https://youtu.be/LuQr6mGxffg
https://youtu.be/LuQr6mGxffg
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Re: Losing GPS on approach
No, it has been happening every flight now. From 13,000 feet in Northern California to short final in Salt Lake City and everywhere in between. It went in to the shop yesterday. I forwarded this thread so I hope that will help the diagnosis. I believe they are planing to replace GPS 1 and antenna. I will report back with the results.haykinson wrote: ↑Thu Jun 22, 2023 6:23 pm Does it always happen in the same area? There are, for example, GPS anomalies that happen in the vicinity of KSMO — for years, I've lost ADS-B coverage due to a loss of GPS at around 1300 AGL, and even had full GPS loss during an approach (fortunately in visual conditions). The airport even had gone through a few weeks of having ATIS declare that GPS is unreliable after the latest bout of issues.
- thommy152
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Re: Losing GPS on approach
I had a similar issues with the Garmin GTN650 in my 182. I replaced the GPS antenna and swapped out the GTN 650 but the problem persisted. It ended being a problem with the COAX cable to the GPS antenna. Once the COAX cable was replaced, the problem never happened again.
2000 C182S (N882SP) / 2023 DA-62 (N271CF).
Commercial ASEL, AMEL, CFI.
Commercial ASEL, AMEL, CFI.