As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB OUT, OIL PRESSURE ON BOTH ENGINES DROPPED TO APPROXIMATELY 50 PSI WITH SLIGHT SURGING. AUTOFEATHER WAS ENGAGED AT THE TIME. MAINTENANCE FACILITY DISCOVERED THAT BOTH OIL COOLER LONG LINES WERE DETERIORATING INTERNALLY. THE HOSES ARE AEROQUIP HOSES PART NUMBER 033 624023-12D0463. THIS BATCH OF HOSE WAS PRODUCED IN THE 3RD QUARTER OF 2004 AS INDICATED ON THE DATA TAG. THE HOSES HAD APPROXIMATELY 7 HOURS USE PRIOR TO FAILURE.