I think mine might have been hardware related. My x55 is giving me issues with the z-axis, it's spiking like crazy whenever there is input to the left. I didn't notice it until I couldn't maintain coordination in a turn and looked down to see my pedals going nuts.
I disabled my z axis and haven't had a crash since. If it happens again I'll post a log.
Also, it occurred both times in the quick dogfight mission.