As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
COMPRESSOR STALL ON NR 4 ENGINE. SUPPLEMENTAL DATA UPDATE THIS IS A GROUP 3 (TAKEOFF ) SURGE DUE TO EXCESSIVE HPC REAR STAGE BLADE TIP CLEARANCE. ENGINE WAS REPLACED AT TERMINATION OF THE FERRY FLIGHT FOR COMPRESSOR REFURBISHMENT. PW4000 ENGINE TAKE-OFF SURGES ARE BEING MANAGED PER AD 2001-25-11