A rigid propeller shaft (part number 3102572-2) from an Allied-Signal (Honeywell) TPE331-12 turboprop engine, was received and examined by the ATSB in order to characterise and assess the nature of an unusual and irregularly finished surface at the end of the forward main bearing/seal journal. The anomalous area had been originally identified during inspection by the engine maintenance provider, who subsequently referred the matter to the Civil Aviation Safety Authority (CASA) through their service difficulty reporting (SDR) system.
The ATSB laboratory examination identified the features associated with the ends of the journal surface as being characteristic of surfaces that had been manually dressed following the application of a plasma/metal sprayed coating to re-build the journal surfaces. Subsequent reference to the inspection/repair manual for the propeller shaft, confirmed that plasma spraying was an approved process for journal repair, and that hand-finishing and deburring was specified for post-spray dressing.
|Date:||09 February 2006||Investigation status:||Completed|
|Location:||Canberra Head Office|
|State:||Australian Capital Territory|
|Release date:||10 July 2007||Occurrence category:||Technical Analysis|
|Report status:||Final||Highest injury level:||None|