Service difficulty report · Blade

Difficulty date
April 20, 2011
Submitted
September 14, 2015
Operation
General aviation
Engine
Pwa PW121
Part
Blade
Condition
Failed
Location
Turbine Section
Stage of operation
NR
How discovered
B
Nature of condition
O
Precautionary procedure
O

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

What was found

(CAN) THE ENGINE WAS INDUCTED FOR INVESTIGATION AND REPAIR DUE TO HIGH ITT. A BORESCOPE INSPECTION OF THE ENGINE REVEALED 2 LP BLADES HAD FAILED. THE HOT SECTION OF THE ENGINE WAS DISASSEMBLED TO INVESTIGATE HIGH ITT AND THE LP BLADE FAILURE. FACTORS WHICH ARE BELIEVED TO HAVE CONTRIBUTED TO HIGH ITT ARE AS FOLLOWS: THE HP DISK WAS UNDERSIZE, THE HP BLADE TIPS WERE HEAVILY ERODED, THE HP SHROUD SEGMENTS WERE HEAVILY ERODED, THE HP TIP CLEARANCE WAS TOO LARGE, THE LP STATOR VANES WERE CRACKED, BURNED, ERODED AND DISTORTED AND 2 LP BLADES HAD FAILED. THE CAUSE OF THE LP BLADE FAILURE WAS DETERMINED TO BE BLADE CREEP.