As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMBOUT THRU FL220 FELT SIGNIFICANT VIBRATION IN FRONT PART OF AIRCRAFT IN BOTH PILOTS SEATS AND RUDDER PEDALS, REDUCED POWER AND LEVELED OFF AND STILL FELT SAME VIBRATION. ALL ENGINE INDICATIONS NORMAL. PERFORMED PROCESS OF TSM TASK 05-50-00-810-801. NO DEFECTS NOTED. UPON FURTHER INSPECTION FOUND PANEL 127BG AT ACCESS DOOR 824 EXTREMELY LOOSE. RE-SECURED PANEL IAW 53-12-13.