Upset in IMC in a military Jet

[Sandyt]

I am testing a new D10/AP74 installation in a Fouga Jet. Generally I am pleased with it but yesterday had a very serious problem. I was climbing through 15,000 feet when the EFIS started showing an left bank and the autopilot followed. The turn rate increased well past rate one and I couldn't understand what was happening till I checked it against the gyro AI and it was showing me inverted!
I assumed it had failed at first but then I used it to recover and saw that the EFIS had failed. It cost me 6000 feet in altitude to get it under control. Once I had it straight and level I re-engaged the AP and it did the same thing again two more times. I didn't allow the AP to follow this time.
Of course I cancelled the mission and headed back to base and on that leg everything worked perfectly.
Anyone got any idea where the problem could lie?

sandy

 

[DBRV10]

As someone who flies in IMC with dueal Dynons, I would like to know as well.

:-?

 

[dynonsupport]

Sandy,

Please get in touch with us at support at dynonavionics dot com

 

[Sandyt]

Tested same aircraft again but in VMC conditions. All normal till passing 15000 ft when steep turn to the left was commanded by EFIS and AP followed. Was in Nav mode with no course turns ahead. Disengaged AP reset target altitude re-engaged and no further issues.
st

 

[DBRV10]

Please report back here also, it may be a one off defect in that unit, but we would all like to know the outcome.

 

[dynonsupport]

So your reports create a host of other questions, but we'd like to work with you directly to figure out what's going on. Please give our support folks a call at 425-402-0433 or email support at dynonavionics dot com.

 

[lolachampcar]

and please continue to post here as I am sure others would be interested in your results...