As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PIT - FL 1052 - DURING CLIMB-OUT FROM PIT, THE NR 2 ENGINE N1 FLUCTUATED3-5 PERCENT. FLIGHT RETURNED TO FIELD AT PIT AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE REMOVED AND REPLACED THE NR 2 ENGINE N1 FAN SPEED SENSOR. RAN ENGINE AT TAKEOFF POWER. ALL INDICATIONS NORMAL WITH NO FLUCTUATIONS NOTED. ALL WORK ACCOMPLISHED IAW WITH MM 77-12-01. (M)