Help Me Learn From This...PFD Failure

Skid

Skid

Pre-takeoff checklist
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Skid
Let me start by saying this is only the 2nd time flying a G1000 equipped C172 so I'm still learning all the intracacies of it all.

So as we were mid leg on a cross country the PFD displayed as such:

pfd.jpg


This only occurred for about 3 seconds and the MFD took over. It would come back online and go off again doing a dance with the MFD. After about 3 iterations of this it started working normal again. It didn't instill much confidence in me so I swung around and returned home.

During this time I tried checking everything electrical. Breakers in, switches good, amps good, no warnings etc.

So being new to this any idea what this was or what to troubleshoot next time?
 
Looks like a connectivity loss, since air data, AHRS, comm, NAV, and transponder all look to be affected.
 
MauleSkinner said:
Looks like a connectivity loss, since air data, AHRS, comm, NAV, and transponder all look to be affected.
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ALL of the busses are affected.

I'd suspect an incorrect system voltage or something equivalently evil.

It's obviously not airworthy.

But the screenshot is a sim. The OP should know what he did to it.
 
Forgive my ignorance as I've never looked at a G1000 panel other than a glance in a magazine, etc. Aren't there backup analog/steam instruments to be able to at least continue VFR flight? Or are you S.O.L. when the pretty color display craps out?
 
Omalley1537 said:
Forgive my ignorance as I've never looked at a G1000 panel other than a glance in a magazine, etc. Aren't there backup analog/steam instruments to be able to at least continue VFR flight? Or are you S.O.L. when the pretty color display craps out?
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In a 172, yes. AI, ASI and altimeter.

All the engine instruments are in the MFD, so it's a land as soon as practicable situation even in VMC if the electrical system screws up this bad.

But I doubt it did for real, since the OP described a reversionary mode that doesn't exist.
 
asicer said:
You forgot the mag compass.

In the C162, you've got nothing and are forced to look out the window.
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Yes, every airworthy plane has a mag compass per 91.205.

Does the 162 have dual AHRS, or are they just not available as IFR platforms?
 
MAKG1 said:
Yes, every airworthy plane has a mag compass per 91.205.

Does the 162 have dual AHRS, or are they just not available as IFR platforms?
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No, 91.205 says "Magnetic direction indicator" which apparently includes a magnetometers since the 162 doesn't have a whiskey compass.

Also, the 162 has a single integrated ADAHRS unit (GSU73). If that completely goes, then there's no backup.
 
asicer said:
No, 91.205 says "Magnetic direction indicator" which apparently includes a magnetometers since the 162 doesn't have a whiskey compass.

Also, the 162 has a single integrated ADAHRS unit (GSU73). If that completely goes, then there's no backup.
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Is it legal for IFR?
 
MAKG1 said:
In a 172, yes. AI, ASI and altimeter.

All the engine instruments are in the MFD, so it's a land as soon as practicable situation even in VMC if the electrical system screws up this bad.

But I doubt it did for real, since the OP described a reversionary mode that doesn't exist.
Click to expand...

Thanks for the info-hadn't considered that the engine vitals would be on there as well.
 
MAKG1 said:
ALL of the busses are affected.

I'd suspect an incorrect system voltage or something equivalently evil.

It's obviously not airworthy.

But the screenshot is a sim. The OP should know what he did to it.
Click to expand...

As briefly as it happened and the surprise it took me by I can't be entirely certain of all the affected instrumentation. I do distinctly remember the comms and navs X'ing out as well as the airspeed, altitude, and VSI tapes. I thought the attitude and heading went out but maybe I saw it wrong. One thing I do remember is the engine instruments jumped to the PFD momentarily as well. It really did feel as though someone was shaking a loose wire.

As to the screenshot that was the first google image I found that resembled the problem.
 
MAKG1 said:
Yes, every airworthy plane has a mag compass per 91.205.

Does the 162 have dual AHRS, or are they just not available as IFR platforms?
Click to expand...

Just because it has a compass, doesn't mean its remotely usable...
 
Skid said:
As briefly as it happened and the surprise it took me by I can't be entirely certain of all the affected instrumentation. I do distinctly remember the comms and navs X'ing out as well as the airspeed, altitude, and VSI tapes. I thought the attitude and heading went out but maybe I saw it wrong. One thing I do remember is the engine instruments jumped to the PFD momentarily as well. It really did feel as though someone was shaking a loose wire.

As to the screenshot that was the first google image I found that resembled the problem.
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BOTH comms and both navs? It's rather important.

A false screenshot leads to false conclusions.
 
MAKG1 said:
It's a sim.
Click to expand...

Well I certainly wouldn't expect him to whip out a camera mid-flight just to get a snapshot of the actual screen instead of flying the plane and trying to troubleshoot what was going on.
 
If I may digress a bit from the conversation there was an experienced CFII who took me in his Seneca early on in the course of my aviation education. Two engines? What do I do now was my initial reaction. I admit to being dumb at that point. He caught me focusing more on the panel than looking out the window. His comment was "You have to learn to fly VFR before learning other things", Doh, who would have thought that? I had to look out the window? Never thought of that. What are those "steam gauges" for if not to keep the plane in controlled flight? Eyes out the window was an unfamiliar concept at that point.
DOH? Did I I have something to learn. You bet your sweet I did. Took that to heart and kept my eyes scanning the horizon.As an A&P without a pilot's certificate there is still much to learn. Only occasionally can I one-up a pilot friend. Getting older day by day but still trying to learn.

Back when I was a kid there was a comic strip named "Too soon old, too late smart". Somehow it rings a bell in my mind. Doesn't it fit all of us to some degree?

Jocularity aside, the ride has been both fun and educational. There was much to learn along the way in the form of regulations, physics of flight, dealing with customers, etc. The picture is already in your mind and does not need further description.

Would I opt into aircraft maintenance again? Yes. It has been satisfying but I would likely go the route Gennn has.
 
MAKG1 said:
In a 172, yes. AI, ASI and altimeter.

All the engine instruments are in the MFD, so it's a land as soon as practicable situation even in VMC if the electrical system screws up this bad.

But I doubt it did for real, since the OP described a reversionary mode that doesn't exist.
Click to expand...

.

So you're saying the OP fabricated the incident and faked the photo? That's a pretty bold claim to make.
 
MAKG1 said:
If it's not, the aircraft is not airworthy per 91.205, for any operation.
Click to expand...

Never been in a DC9 or derivative of one? Sure, there's a compass, but its not remotely usable...
 
MAKG1 said:
BOTH comms and both navs? It's rather important.

A false screenshot leads to false conclusions.
Click to expand...

I'm pretty sure it was both. Sorry I can't be more specific, there were just more red X's than not and the entire event was relatively brief. It was almost as if it looked like the entire system was starting for the first time and reinitializing. Reason I say this is not only because of the short duration of the red X's but the engine instruments jumping around from the mfd to the pfd a few times.
 
3393RP said:
.

So you're saying the OP fabricated the incident and faked the photo? That's a pretty bold claim to make.
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He definitely faked the "photo." It's a screenshot of a sim, not a photo.

As for the incident, the PFD doesn't jump over to the MFD and back on its own. There is a button for that.
 
MAKG1 said:
He definitely faked the "photo." It's a screenshot of a sim, not a photo.

As for the incident, the PFD doesn't jump over to the MFD and back on its own. There is a button for that.
Click to expand...

So again, yes the photo is from google images and a crude example of what I feel like I saw. Not trying to fake anything.

And I think I misspoke in the op. I meant the mfd was the only thing appearing to be working, with the engine instruments swapping back and forth.
 
Skid said:
So again, yes the photo is from google images and a crude example of what I feel like I saw. Not trying to fake anything.

And I think I misspoke in the op. I meant the mfd was the only thing appearing to be working, with the engine instruments swapping back and forth.
Click to expand...
Search up the G1000 Pilots Guide for "reversionary mode". Let us know if that's what you saw.
 
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