As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(AUS) AFTER TAKE-OFF, THE GEAR DOOR DISAGREE MESSAGE WARNING DISPLAYED AND EXCESSIVE NOSE GEAR VIBRATIONS WERE FELT DURING GEAR RETRACTION. GROUND INVESTIGATION FOUND THAT THE NLG PRIORITY VALVE'S PISTON SEAT ASSEMBLY PNO 01715201B2-1 HAD FRACTURED PREVENTING BALL PNO MS134359 FROM SEATING.