As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AFTER GEAR-UP SELECTION THE AIRCRAFT ENCOUNTERED A VIBRATION, FELT THROUGHOUT ENTIRE PLANE,THAT WOULD INCRESE/DECREASE WITH THROTTLE MOVEMENT. AIRCRAFT RETURNED TO THE ORIGINATING DEPARTURE STATION AND LANDED SAFELY. MAINTENANCE FOUND NR 1 ENGINE FAN BLADES DAMAGED & BIRD REMAINS ON OIL COOLER, DUE TO A LARGE BIRD INGESTION.