As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTO PILOT PITCHED OVER FROM LEVEL FLIGHT AT FL360 AND MACH .78 OR 260 KTS IND. WE LOST 450 FT UPON THE VIOLENT PITCHING MOMENT AND VERY ABRUPT TAIL FLUTTER. THIS HAPPENED ON THE L-AFCS, FLIGHT DIRECTOR VERY ERRATIC IN ALL MODES AFTER PITCHING MOMENT. REPLACED FLAP COMPENSATOR TRANSMITTER (POTENTIOMETER) PERFORMED CALIBRATION CHECK PER HAWKER 800 XP M/M 34-22-60-501 AND OP'S CHECKED IAW HAWKER SERIES COMMUNIQUE NR 22-07. NO OTHER FAULTS NOTED AT THIS TIME.