As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
VIBRATION ON NR 1 ENGINE, EEC MODE EICAS ILLUMINATED, EGT FLUCTUATED BETWEEN 120 AND 180 AT IDLE, EPR INDICATION LOST, N1 & N2 INDICATIONS NORMAL. CREW ELECTED TO SHUT DOWN ENGINE AND RETURN TO FIELD. *S/D* 1 EA T2 BLADE FAILED AT THE PLATFORM. 2 EA ADJACENT BLADES WERE BROKEN OFF AT MID SPAN. THE RESULTANT HIGH N2 VIBRATION CAUSED THE P4.95 MANIFOLD TO FAIL WHICH CAUSED LOSS OF EPR INDICATION AND REVERSION TO ALTERNATE MODE. ENGINE WAS REMOVED FOR REFURBISHMENT.