A/P Disengages and can't reengage.
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This happened twice.
I flew on LNAV until vectors. After I turned the plane away from the airport, using heading switch, per vectors, the A/P disengaged. When I went to turn it back on, it would not reengage from either seat.
Both times, the speed was approximately 170, the level was about 3,000 ft. FD was both on, autothrottle was on, ILS was programmed, and the plane was facing away from the airport by about 5-10 NM. The turn made from vectors instructions.
Any advice on where to look? Been flying only RJ for a short time and have most experience on Boeing. So, not sure what might be going on or some "Boeing" habit I might have kept.
Greg
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This is a tricky one to diagnose without seeing what exactly happened in the sim.
Do you recall why the autopilot disengaged? Was it disengaged via the button on the yoke/control assignments, or was the emergency disconnect bar used on the MCP? If the emergency disconnect bar was used, then it will need to be reset back to the UP position before the autopilot can be engaged again.
Another potential factor is the airspeed of 170 knots. Depending on the aircraft's weight at the time, 170 knots will likely fall below the stall speed with flaps retracted, so if flaps were still retracted, the aircraft's stall protection may intervene by disconnecting the autopilot and preventing it from being reengaged until speed has sufficiently increased.
The conditions for autopilot engagement and autopilot disengagement can be found on pages 95-96 of the RJ Professional Operations Manual: https://downloads.justflight.com/products/JFF003765/RJ_Professional_MSFS_Operations_Manual_MSFS2024.pdf
Hope that helps.
Mark - Just Flight
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Mark
Thanks. Will look at the attachment. The stall lights were flickering now that you noted that could be the issue. I just did another flight, same route and my airspeed on the vectors was 200 and had no problems. I'm going to consider this the fix unless some issue happens again. But I might try to intentionally stall it to see if it triggers the prior action. Thanks Greg
