As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED; BEGINNING AT CLIMB OUT OF 4000, GRINDING, SCRAPING SOUND ACCOMPANIED BY VIBRATION UNDER FEET, POSSIBLY ASSOCIATED WITH ANGLE OF ATTACK. OCCURRED PERIODICALLY. CORR ACTION MX FOUND LOOSE BOLT ON REAR HINGE BRACKET OF RH NLG DOOR. RE-TORQUED BOLT. AIRCRAFT WAS FLIGHT TESTED FOR VIBRATIONS. NO ABNORMAL VIBRATIONS DETECTED AT THIS TIME. OPS CHECK GOOD.