Avidyne Homepage
Forum Home Forum Home > Avidyne General > IFD 5 Series & IFD 4 Series Touch Screen GPS/NAV/COM
  New Posts New Posts RSS Feed - GPS Failure in flight
  FAQ FAQ  Forum Search   Register Register  Login Login

GPS Failure in flight
 Post Reply Post Reply
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
D-EACY View Drop Down
Groupie
Groupie


Joined: 29 Dec 2018
Location: Munich
Status: Offline
Points: 96 		Post Options Post Options   Thanks (0) Thanks(0)   Quote D-EACY Quote  Post ReplyReply Direct Link To This Post Topic: GPS Failure in flight
    Posted: 23 Aug 2024 at 3:58am
On a 2:30 IFR last week my Entegra MFD went black and restarted after 3 minutes. Now works fine again.

YESTERDAY, on a VFR flight over flat terrain, my IFD440 #1 lost all satellites - #2 had all satellites.

I switched the navigation to GPS 2 and waited nothing. I had to power down #1 and restart it – and immediately it had ll satellites again and worked fine.

Also: After the #1 GPS had rebooted the #2 GPOS showed VLOC and could not be switched to GPS. I had to power it down aswell and when it restarted it showed "GPS" again.

Will these GPS problems ever have an end. I really love Avidyne avionics and I made a couple of Cirrus pilots switch to IFDs and the DFC90. Terrific products. 

But OTOH I have a GNS430W in my other plane and it has not failed once in 20 years ... I bought two 440s for my SR22 in 2018 and they were both exchanged one year later (slow GPS lock on) and one was exchanged again another year later (white screen). 

Not good. 


Edited by D-EACY - 23 Aug 2024 at 3:59am
2006 SR22-G2 DFC90 IFD440
Back to Top
ansond View Drop Down
Senior Member
Senior Member


Joined: 12 Nov 2009
Location: Austin, Texas
Status: Offline
Points: 151 		Post Options Post Options   Thanks (0) Thanks(0)   Quote ansond Quote  Post ReplyReply Direct Link To This Post Posted: 23 Aug 2024 at 10:24am
I have basically had the same experience with one of my IFDs (everything was working perfectly, then my IFD #1 suddenly lost all GPS association.. I looked at the GPS status page and it had tasked 0 satellites.) 

I did NOT reboot...I just left the IFD as-is and it eventually re-tasked (about 5 minutes later) and worked as I would have expected.  I did download and check the logs - I found 0 log entries indicating some sort of problem or issue.  I double checked all of my antenna wiring (all are gold-plated BNC/TNC connectors, professionally installed, using the highest standard RG142 cable... no issues were found).   IFD#1 is connected to my CI-428-410 Comant antenna... no issues found with that either. 

I'm not sure what happened - I just flew nearly 6 hours and both IFDs performed ***perfectly***.  From the "sudden-ness" of the loss of all satellites/association (it was literally "fully associated SBAS" to "everything gone" in an instant...) , I assume the problem is the IFD GPS software - the GPS stack in the IFD might have a few bugs in it that can cause it to effectively "reset".  Never seen this in any of my previous Garmin 430's.  10.3.1.2 is installed.  

Question for Avidyne:  Do your IFDs use any software from Microsoft?  Windows Embedded/Core?  Just curious.  Some of the UI look/feel and filename extensions would indicate that might be the case. 

Just FYI!  Safe flying! 
Back to Top
D-EACY View Drop Down
Groupie
Groupie


Joined: 29 Dec 2018
Location: Munich
Status: Offline
Points: 96 		Post Options Post Options   Thanks (0) Thanks(0)   Quote D-EACY Quote  Post ReplyReply Direct Link To This Post Posted: 23 Aug 2024 at 10:30am
In my case the #1 GPS is connected to a GA-35 antenna that was installed new on top of the fusleage in 2018 when I first got the IFDs.

#2 is connected to a COMANT 2580-200 combined COM-GPS-WAAS antenna that replaced the original COM 1 antenna. 

Although both units (M18 and M19 serials) are exchange units they are pretty slow aquiring GPS after GPS, but I got used to that. 

A failure in flight though is more critical. They Skywatch traffic,, the EGPWS and the Stormscope all run off the #1 unit, so all these systems fail immediately without GPS.

PS: I also have 10.3.1.2


Edited by D-EACY - 23 Aug 2024 at 10:44am
2006 SR22-G2 DFC90 IFD440
Back to Top
ansond View Drop Down
Senior Member
Senior Member


Joined: 12 Nov 2009
Location: Austin, Texas
Status: Offline
Points: 151 		Post Options Post Options   Thanks (0) Thanks(0)   Quote ansond Quote  Post ReplyReply Direct Link To This Post Posted: 24 Aug 2024 at 9:11pm
FYI... another flight today in (hot!!) Austin TX and not a single issue... both IFDs worked flawlessly and had full GPS lock for the entire flight without issue. 

Wondering if there might be a way to differentiate, in a future version of AviOS, when the GPS antenna goes missing vs. a GPS stack/subsystem fault... that is, it would be beneficial if, instead of a more generic "GPS Fault" error.. that error would only be displayed if the GPS subsystem and/or software stack failed for some reason... if the antenna goes missing, perhaps that specific condition could be detected and a "GPS Signal Lost" message could be dispatched vs. the generic "GPS Fault"... thoughts?  Possibly ditto for the NAV stack and/or COM stack as well... just a thought. 

Doug
N208LG


Edited by ansond - 24 Aug 2024 at 9:14pm
Back to Top
AviSteve View Drop Down
Admin Group
Admin Group
Avatar

Joined: 12 Feb 2018
Location: Melbourne, FL
Status: Offline
Points: 2244 		Post Options Post Options   Thanks (1) Thanks(1)   Quote AviSteve Quote  Post ReplyReply Direct Link To This Post Posted: 27 Aug 2024 at 8:29am
Originally posted by ansond ansond wrote:

...Question for Avidyne:  Do your IFDs use any software from Microsoft?  Windows Embedded/Core?  Just curious.  Some of the UI look/feel and filename extensions would indicate that might be the case. 

Nope, IFDs don't contain any Microsoft components.
Steve Lindsley
Avidyne Engineering
Back to Top
D-EACY View Drop Down
Groupie
Groupie


Joined: 29 Dec 2018
Location: Munich
Status: Offline
Points: 96 		Post Options Post Options   Thanks (0) Thanks(0)   Quote D-EACY Quote  Post ReplyReply Direct Link To This Post Posted: 27 Aug 2024 at 10:16am
Hi,
I have sent my logs to pilotsupport two days, ago. Do you know anything about them? 
2006 SR22-G2 DFC90 IFD440
Back to Top
ansond View Drop Down
Senior Member
Senior Member


Joined: 12 Nov 2009
Location: Austin, Texas
Status: Offline
Points: 151 		Post Options Post Options   Thanks (0) Thanks(0)   Quote ansond Quote  Post ReplyReply Direct Link To This Post Posted: 27 Aug 2024 at 3:46pm
Thanks Steve!  was simply curious as the log filenames look that way... thanks for the update.  


Edited by ansond - 27 Aug 2024 at 3:46pm
Back to Top
AviSteve View Drop Down
Admin Group
Admin Group
Avatar

Joined: 12 Feb 2018
Location: Melbourne, FL
Status: Offline
Points: 2244 		Post Options Post Options   Thanks (0) Thanks(0)   Quote AviSteve Quote  Post ReplyReply Direct Link To This Post Posted: 28 Aug 2024 at 9:24am
Originally posted by D-EACY D-EACY wrote:

Hi,
I have sent my logs to pilotsupport two days, ago. Do you know anything about them? 
I know that people have been looking at them, but don't know of any conclusions at this point.
Steve Lindsley
Avidyne Engineering
Back to Top
JohnP View Drop Down
Newbie
Newbie


Joined: 16 Sep 2024
Location: Georgia
Status: Offline
Points: 2 		Post Options Post Options   Thanks (0) Thanks(0)   Quote JohnP Quote  Post ReplyReply Direct Link To This Post Posted: 16 Sep 2024 at 10:44am
I am watching this thread closely.  I have a new IFD 440 that I installed this spring as part of a complete panel redo.  It has been working great for well over 100 hours.  Then, a few days ago,  I was flying home from a nearby airport  and it failed to get a GPS "alignment".  Upon returning, I powered it down and restarted it while sitting outside of the hangar.  It took several minutes but  eventually I got a green GPS status.  

The next morning I took off IFR and it worked fine for the three hour flight.  A short flight the next day was also fine.  Then yesterday when getting ready to depart Ocean City NJ it would not align.  20 minutes on the ground and it eventually picked up 10 satellites but still no green GPS.  I departed VFR for a long flight home.  After 20 or 30 minutes in the air still no GPS.  One or more times I received a GPS failure message.  I rebooted it in the air and it eventually gave me a green GPS status and then worked fine for the remaining 3 hours or so.

10.3.1.2 software and current database.

I also noticed that the status eventually got to SBAS Nav but the GPS indication was still yellow and it was not sending any route information to my EFIS.  This was the case on the ground and in the air.  A reboot on the ground did not help.  The reboot in the air did help. (see the first photo.)  The second and third photos were taken on the ground.  It looked pretty much the same int he air before the reboot.  There was a fair bit of satellites going in and out of view, or of the boxes tuning yellow while I was having problems.

My three non-IFR GPS sources had no problems during this time.

John
Back to Top
AviSteve View Drop Down
Admin Group
Admin Group
Avatar

Joined: 12 Feb 2018
Location: Melbourne, FL
Status: Offline
Points: 2244 		Post Options Post Options   Thanks (0) Thanks(0)   Quote AviSteve Quote  Post ReplyReply Direct Link To This Post Posted: 16 Sep 2024 at 10:49am
Originally posted by JohnP JohnP wrote:

...I also noticed that the status eventually got to SBAS Nav but the GPS indication was still yellow ...

The GPS indication in the upper right corner of the IFD indicates the status of the "selected nav source", not just the health of the GPS.  If there is no active flight plan in the IFD, the "GPS" will remain yellow.
Steve Lindsley
Avidyne Engineering
Back to Top
JohnP View Drop Down
Newbie
Newbie


Joined: 16 Sep 2024
Location: Georgia
Status: Offline
Points: 2 		Post Options Post Options   Thanks (0) Thanks(0)   Quote JohnP Quote  Post ReplyReply Direct Link To This Post Posted: 16 Sep 2024 at 11:08am
Thank you.  I had the flight plan activated on the ground but I may not have reactivated it after rebooting.  I don't remember.

If rebooting does the fp need to be reactivated?  I noticed when rebooting that I did not get the initial screen with all the white lettered language where I have to press enter and then confirm and such.
Back to Top
AviSteve View Drop Down
Admin Group
Admin Group
Avatar

Joined: 12 Feb 2018
Location: Melbourne, FL
Status: Offline
Points: 2244 		Post Options Post Options   Thanks (0) Thanks(0)   Quote AviSteve Quote  Post ReplyReply Direct Link To This Post Posted: 16 Sep 2024 at 11:15am
Yes, if you're doing a ground test, you'll need to enter and activate the flight plan.  "Activate Flight Plan" is a button on the FPL page.  The IFD will automatically activate the flight plan if the groundspeed exceeds 40 knots.
Steve Lindsley
Avidyne Engineering
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.159 seconds.