As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRPLANE SHAKES DURING CLIMBOUT AT SLOW SPEED AND DURING APPROACH. CAPTAINS CONTROL COLUMN SHAKES. MOVES APPROXIMATELY 3 INCHES. VIBRATION DIMINISHES SOME IN CRUISE FLIGHT. VIBRATION STOPPED COMPLETELY WHEN FLAPS SELECTED TO 15 DEG ON APPROACH.