Service difficulty report · Blade · Boeing 777222

Difficulty date
June 27, 2008
Submitted
July 2, 2008
Operation
Air carrier
Aircraft
N791UA
Make and model
Boeing 777222
Aircraft serial
26933
Aircraft time
47,426 hours, 7,104 cycles
Engine
Pwa PW4090
Engine time
24,575 hours, 3,206 cycles
Part
Blade
Condition
Damaged
Location
Nr 2 Engine
Stage of operation
IN
How discovered
B
Nature of condition
W
Precautionary procedure
K

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

What was found

NR 2 ENGINE FAILED BOROSCOPE INSP 2ND STAGE BLADES HAS 2 EACH BLADES WITH DAMAGE. ENGINE REPLACED. TWO HP TURBINE STAGE-2 BLADES WERE FOUND WITH MISSING PORTIONS OF THE CONCAVE AIRFOIL PLATFORM. THE FAILED BLADES, SERIAL NOS. CKLBHY9532 & CKLBHY7580 HAD IDENTICAL TIMES AND CYCLES. NUMEROUS OTHER STAGE-2 BLADES HAD RESULTANT DAMAGE. ALSO, STAGE-3 VANES HAD DAMAGE REQUIRING LP TURBINE DISASSEMBLY.