SDR 2007UALA02616

Service difficulty report · Blade · Boeing 767322

Difficulty date: July 13, 2007
Submitted: July 17, 2007
Operation: Air carrier
Aircraft: N653UA
Make and model: Boeing 767322
Aircraft serial: 25391
Aircraft time: 64,529 hours, 10,629 cycles
Engine: Pwa PW4060
Engine time: 30,648 hours, 8,164 cycles
System (JASC): 7250 · Turbine Section
Part: Blade
Condition: Fractured
Location: Nr 1 Engine
Stage of operation: CR
How discovered: O
Nature of condition: E
Precautionary procedure: E

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

CREW SHUTDOWN THE NR 1 ENGINE DUE TO VIBRATION. LANDED UNDER AMBER ALERT. [08-14-07] ENGINE REPLACED AT IAD. SHOP TEARDOWN FOUND ONE STAGE-2 HPT BLADE FRACTURED AT THE PLATFORM. THIS CAUSED AN UNBALANCE THAT PRODUCED HEAVY VIBRATION. FAILURE RESULT OF UNDER PLATFORM STRESS CORROSION CRACKING. A NEW CONFIGURATION BLADE, WITH IMPROVED UNDER PLATFORM COATING TO ELIMINATE STRESS CORROSION CRACKING IS AVAILABLE. THIS NEW CONFIGURATION BLADE IS BEING INCORPORATED INTO UNITED'S FLEET AT HPT BUILD.