As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAKEOFF, THE NR 1 ENGINE N1 WENT TO ZERO WITH VIBRATION NOTED. THE ENGINE WAS SHUT DOWN, DUMPED 55.000 LBS OF FUEL AND THE AIRCRAFT RETURNED TO SFO WITHOUT FURTHER INCIDENT. MAINTENANCE INSPECTION REVEALED A BIRD STRIKE. PERFORMED ENGINE RUN-UP AT TAKEOFF POWER AND NO VIBRATION WAS EXPERIENCED.