While flying the DA62 (with current DA62X modifications) at 12,500' and 159 knots on GPS/AP - the plane reached the next waypoint (number 5 in a flight that had been cruising at FL12.5 for over an hour) and the PFD showed the change in waypoint and the bearing to the new waypoint.  The plane started to make the 15° degree turn to starboard to head to waypoint 6 when it suddenly rolled hard to the left, dropped the left wing tip, and went into a rapid spiral descent, which led to inverted flight at greater than VNe in less than 10-seconds.  I tried to recover by turning off the AP but the elevator was trimmed full down and I could not trim it up fast enough to keep the plane from exceeding VNe.  As the elevator trim moved to neutral and I began to have some elevator authority - I exceeded the G-limit and the screen went black.

This was on a saved flight.  The first time I made the flight - the same thing had happened at waypoint 3.

The same thing has happened to me twice in the Robert Young G36T Bonanza.  At a waypoint (never the same one) the plane begins to turn to the next waypoint and then suddenly rolls into a rapid spiral descent and inverted flight exceeding VNe.

Clear stable air with no ice at every occurrence.  It happens at 500' AGL, 5,000' AGL and FL12.  It happens from the top of the white arc to the top of the green arc. 

I am using Working Title G1000 v0.3.2

Is this a know problem and if so - is there a fix?  The event is quite intermittent - it happens about once every five or ten flights but it is always in either the DA62 or G36.  I fly a lot in the C-172/G1000 and have never seen the problem.  

Edited December 8, 20205 yr by TacomaSailor
correct source of DA62X modification

31 minutes ago, TacomaSailor said:

While flying the DA62 (with current Robert Young modifications)

I thought Robert had decided not to release his DA62 mod because of the current AP problems. Where is it available?

Thx,

Al

This sounds a lot like the "integral windup" death spiral that people reported on the A320 after the recent (Nov 24th) Asobo patch changed the core, un-alterable AP logic. 

I haven't personally seen this on the Turbo Bonanza, but based on the information that Matt from the FlyByWire team received directly from Asobo I think it could happen on all aircraft. 

It's very difficult to debug due to the intermittent nature.  Asobo is working on updates for the next patch, so spending a lot of time on tuning the Asobo AP right now might be wasted in a couple of weeks.

(Note that this is a separate issues from the "slow heading capture" issue also introduced by same patch)

Edited December 8, 20205 yr by marsman2020

29 minutes ago, ark said:

I thought Robert had decided not to release his DA62 mod because of the current AP problems. Where is it available?

Thx,

Al

You are correct - I am flying the DA62X mod which implements a form of FADEC for the engines