Engines

PRATT & WHITNEY-CAN, PW120A
SDR # 20101122002
 
Engine Propeller Shaft Crack

SDR submitted:

During a pre-flight walk around, the pilot noticed an external oil leak from the propeller shaft area. A more detailed inspection revealed a crack almost half way around the circumference of the shaft at approximately 10 to 11.5 cm (4 to 4.5 inches) from the front flange.

The engine was removed and replaced and the aeroplane was made serviceable.

Transport Canada Comments:
The propeller shaft was sent for further investigation to Pratt & Whitney Canada (PWC) where preliminary visual inspection and metal testing have confirmed that the crack was caused by hydrogen embrittlement.

PWC are progressing with a more in-depth investigation and have issued Service Information Letter PW100-139 as well as Service Bulletin 21798 advising all PW100 Series engine operators of this possible scenario.

Transport Canada Civil Aviation would like to emphasize to all affected operators the importance for thorough flight crew and maintenance awareness when addressing propeller shaft oil leaks. Hammer and wrench in X formation indicating end of article

View of the crack from inside the propeller shaft

Date modified: