Malibu veers to right coming off AP on approach?

[fppilot 4,339]

Don't see that anyone else reported this issue, so I assume it is something I am doing wrong in respect to this aircraft. I do not have with any other model the issue I am about to describe. Flying three different RNAV/LPV approaches today (three totally different airports, all in Minnesota) with the RXP530 and AP coupled for LPV approaches, when I got inside the OM and clicked off the AP to take manual control, the Malibu veers off to the right and in one case pitched the nose up as well. I checked my yaw damper setting after the first occurrence, and turned it off before the second approach. That made no difference. I looked at other control settings and did not identify any other culprits. Anyone got any ideas?

 

My download date from the Carenado site was 2/4/2012, so the service packs and updates should be incorporated into what I have.

[fppilot 4,339]

Somehow got it worked out. When the issue was happening I was flying a type-familiarization circuit, landing at each airport, taxiing to ramps, entering the next GPS flight plan, then flying the next segment. Didn't shut down. Didn't restart FSX. So the issue continued on each approach in the circuit. After the circuit I shut down. Exited FSX. Grilled some chicken and ate dinner. Rebooted. Then took off, circled, and flew one of the affected approaches again. This time no issue. I used to have a yoke rocker switch configured for rudder trim, but no longer, so I don't know what happened. Can't imagine I triggered keystrokes to set the rudder trim off. Anyway, all is good.

[Gregg_Seipp 565]

Gotta ask...did you engage NAV before you clicked APR?

[fppilot 4,339]

Gotta ask...did you engage NAV before you clicked APR?

 

Gregg. Not sure what your question is. I was in IMC for all three segments, flying IFR with AP and the RXP. So certainly I was using the NAV function for the routes before activating the APR function each time on final. I've logged right at 100 flights between 1 Nov and today, and have likely flown LNAV or LPV approaches on half of them. The only difference yesterday was that I was logging some time and approaches in the Malibu to gain more familiarization with it.

 

All I can guess is that I inadvertently applied some rudder trim during the first segment and then that undetected error on my part carried over and affected all three approaches. I left St Paul Downtown (KSTP) and flew to International Falls, then Duluth, then back to St Paul. I did full stop landings, taxi, takeoff at KINL and KDLH, and flew RNAV 32 approach to St Paul as I had done earlier in the day in the C90. Odd though that I did not sense any rudder trim during takeoffs and initial climbs. I don't normally engage the AP until climbing through 1,000.

 

Again, after "ending" the flight, exiting FSX, rebooting, then taking off and shooting another approach into St Paul I encountered no issue at all. So life is good.

[Gregg_Seipp 565]

I don't have the Malibu, though, I have several similarly configured aircraft. I haven't seen how a trim setting could mess with the autopilot. In fact, I think the autopilots tend to diss the trim (since autopilots generally use trim to control the aircraft.) My guess, at this point, is that it was just one of those 'FSX things' that happens from time to time. It does sound very similar to what was happening to me last week, though, with another RXP equipped airplane.