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  #11  
Old 06-08-2020, 07:23 PM
Kooshball Kooshball is offline
 
Join Date: Dec 2018
Location: NC
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Solved! It seems that there never really was an issue...when the unit sees airspeed but no GPS ground speed it gets confused and displays all kinds of obstacles which is what those lines are.

Too bad it can?t deal with that but I?m glad there isn?t an issue with the unit.

Thx for all the replies!
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  #12  
Old 06-08-2020, 08:35 PM
Jpm757 Jpm757 is offline
 
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So if your GPS fails in-flight, that's what you get?
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  #13  
Old 06-08-2020, 11:57 PM
BobTurner BobTurner is offline
 
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This is strange. I have a GRT Hx. I?ve tested the pitot using the Hx and a vinyl tube over the pitot, inside the hangar where there is no gps signal. I never see those lines. I do lose synthetic vision since it doesn?t know where it is.
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  #14  
Old 06-09-2020, 12:33 AM
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rv8ch rv8ch is offline
 
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Quote:
Originally Posted by Kooshball View Post
Solved! It seems that there never really was an issue...when the unit sees airspeed but no GPS ground speed it gets confused and displays all kinds of obstacles which is what those lines are....
Did they see that picture? It's hard to imagine that they would think this is normal...

I had a pitot static test done on mine inside the hangar and didn't see this. My hanger may have allowed some GPS signal in, since it's quite old, and has some plexi tiles for light.

I have not tested something like this while disconnecting the GPS antenna or covering it with multiple layers of something that will prevent a signal from coming in, but I might.
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  #15  
Old 06-09-2020, 05:30 AM
Kooshball Kooshball is offline
 
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Quote:
Originally Posted by rv8ch View Post
Did they see that picture? It's hard to imagine that they would think this is normal...

I had a pitot static test done on mine inside the hangar and didn't see this. My hanger may have allowed some GPS signal in, since it's quite old, and has some plexi tiles for light.

I have not tested something like this while disconnecting the GPS antenna or covering it with multiple layers of something that will prevent a signal from coming in, but I might.
Just to clarify...I am getting a GPS signal in the hangar...just no movement. When the issue starts you can actually see the flight path marker start moving and go off to the right then disappear as the bars show up.

GRT has seen the pic, a video and a few more pics and are telling me it is normal but it still seems strange.
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  #16  
Old 06-09-2020, 06:48 AM
YellowJacket RV9 YellowJacket RV9 is offline
 
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Location: Clearwater, FL KCLW
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The same happens to me. Seems the AHRS is confused when it gets airspeed data but the gps says it is sitting still. That?s different than losing gps altogether. The AHRS synthesizing a lot of data and freaks out when it doesn?t fit, apparently.

Not an issue in the air. I have lost gps in flight briefly and the display was rock solid.

Chris
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  #17  
Old 06-09-2020, 08:51 AM
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Radomir Radomir is offline
 
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do these lines show if you actually increase altitude?? The pic posted shows you're "flying low" so obstacles are an issue..
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