Page 1 of 1
Loss of control w/electronic attitude indicators
Posted: Mon Sep 04, 2023 3:10 pm
by GAHorn
Can you believe that this guy managed to survive after having suffered such loss of control..?
(While in IMC…he was fortunate to be over a valley….).
- Click to ENLARGE
The report:
https://www.tsb.gc.ca/eng/rapports-repo ... p0001.html
Re: Loss of control w/electronic attitude indicators
Posted: Tue Sep 05, 2023 12:00 am
by ghostflyer
OMG this is one lucky guy, It’s a wonder the aircraft didn’t break up in flight . I think Garmin has a lot to answer for this situation. Not wishing to start rumours but this is not the first time I have heard of a similar situation with this instrument . I am under the impression it doesn’t like voltage spikes .
Re: Loss of control w/electronic attitude indicators
Posted: Tue Sep 05, 2023 12:13 pm
by rnealon1
Most interesting to me are the following statements from the Transportation Safety Board investigation report:
"The investigation attempted to determine more precisely the source of the initial fault. However, no supplemental information about the instrument, possible reasons it would require realignment while the aircraft was in flight, or analysis of the occurrence aircraft’s recorded fault logs were provided to the investigation by Garmin."
"The investigation was unable to find the trainer app and it was not provided to the investigation by Garmin."
These statements give the impression that the investigators were being stonewalled by Garmin.
Re: Loss of control w/electronic attitude indicators
Posted: Tue Sep 05, 2023 3:56 pm
by mmcmillan2
Wow, a GI275! He is lucky to have made it. I’d love to see pictures of his panel. I wonder what he had for backup indicators.
Re: Loss of control w/electronic attitude indicators
Posted: Tue Sep 05, 2023 4:54 pm
by n2582d
Vne + 70 knots!
I'm ready to buy a Mooney ... with a venturi-powered attitude indicator!
Re: Loss of control w/electronic attitude indicators
Posted: Tue Sep 05, 2023 8:26 pm
by bjan11
This report has been doing the rounds for a while. It does a poor job of highlighting the actual error, which is:
The Garmin GI 275 MFI is an electric, solid state, highly configurable upgrade for many traditional round-gauge instruments, such as ADIs and HSIs, which contain mechanically driven gyros traditionally powered by a vacuum-driven engine pump. It can be configured as either a primary or a standby instrument. [...] When a standby ADI or HSI detects a fault from a compatible interconnected unit, it will automatically switch to reversionary operation mode, which means it “exclusively behaves as a Primary ADI unit until the fault is resolved.” This mode can also be manually selected from a panel-mounted switch.
[...]
Because both of these instruments were configured as primary units, a reversionary switch was not installed, nor was it required to be.
The aircraft’s owner and the occurrence pilot both thought that if a fault was detected in the ADI, the HSI would either automatically enter the reversionary operation mode and display the ADI page, or the pilot would be able to select the ADI page manually. Therefore, their understanding of both the system’s automation and the units’ reversionary capabilities was incorrect.
When the GI-275 Primary ADI was installed, the installer should have reconfigured the GI-275 HSI as a HSI+standby ADI. If they had done that, this would have been a non-event. It has nothing to do with voltage spikes or other vague hand-waving.
With glass panels, you need to understand your instruments and their reversionary modes, and you need to make sure your installer does too. Just like vacuum systems.
Re: Loss of control w/electronic attitude indicators
Posted: Tue Sep 05, 2023 10:06 pm
by Ryan Smith
In about 10K hours of flying, I’ve lost count of how many vacuum attitude indicators I’ve had fail. The GI-275 is a great instrument. Sounds like this was a discussion about lack of partial panel proficiency as much as it is one of component failure.
I’m debating the investment of installing two of these in my 170, and I’m either going to put four of them or a G3X with one as a standby in my Bonanza.
Re: Loss of control w/electronic attitude indicators
Posted: Sun Sep 10, 2023 1:26 am
by ghostflyer
The Garmin G3x is a great stable instrument[system ] and a back up that has least issues is a garmin G5. There is a recall on G5 batteries but Garmin has that under control.