As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LANDING GEAR WAS RETRACTED. 40 MINUTES INTO FLIGHT, PILOT HEARD LOUD BANG. AIRCRAFT LANDED WITH MAINS EXTENDED AND LOCKED. NOSE GEAR PARTIALLY RETRACTED. UPON INSPECTION, FOUND UPLOCK TORQUE TUBE END STUD BROKEN OFF (.25 INCH - 28 STUD. NEW VERSIONS HAVE .3125 INCH STUD). SUBMITTER RECOMMENDED INSTALLING BEEFIER UNIT.