As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - FLT 5727 - HIGH PITCH HUM HEARD IN COCKPIT AFTER TAKEOFF WITH VIBRATION FELT IN FLIGHT CONTROLS, POWER LEVERS, TILLER, AND FLOOR. MAINTENANCE PERFORMED OPS CHECK OF ENTIRE SYSTEM WITH NO DEFECTS NOTED. TEST FLIGHT WAS PERFORMED AND FOUND SATISFACTORY. (M)