As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING LEFT ENGINE START AT APPROXIMATELY 30 PERCENT N1, A GRINDING NOISE WAS HEARD AND STRANGE VIBRATION FELT IN LEFT PROP LEVER. SHUT DOWN ENGINE. DEMATED POWER SECTION FROM GAS GENERATOR AND DETERMINED THAT POWER TURBINE BLADES FAILED. POWER SECTION HAS INTERNAL DAMAGE. REPLACED LT POWER SECTION MODULE AND ROUTED FAILED UNIT FOR FURTHER ANALYSIS AND REPAIR. CONFIRMED 2ND STAGE POWER TURBINE BLADE FAILURE. SUBSTANTIAL DAMAGE OCCURRED. FULL OVERHAUL OF POEWR SECTION REQUIRED. (M)