Aviation safety investigations & reports

In-flight engine failure, 93km N of Perth Airport, WA, 27 November 2006, Beechcraft King Air 200, VH-XDB

Investigation number:
AO-2006-007
Status: Completed
Investigation completed

Summary

Download Final Report
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On 27 November 2006, a Beechcraft King Air 200 aircraft, registered VH-XDB and carrying two crew and six passengers, was on a flight from Mount Hale to Perth, Western Australia. Shortly after commencing the decent into Perth airport, the right engine failed catastrophically.

An engineering examination of the failed Pratt and Whitney Canada PT6A-41 turboprop engine was performed and revealed that the first-stage 'sun' and 'planet' gear set within the propeller reduction gearbox had decoupled from the power turbine. The decoupling allowed the power turbine to overspeed, which resulted in destruction and shedding of the turbine blades. Several blade fragments punctured the outer gas generator case.

A metallurgical examination of the failed first-stage gear set revealed that a mismatch in service histories between the sun gear and planet gears was the most likely contributor to the failure. The engine manufacturer had been alert to the occurrence of reduction gearbox distress due to gear mismatching at overhaul.

Following this incident, the aircraft operator initiated a review of their system of maintenance with respect to monitoring of life-limited engine components, for all PT6A engines in their fleet.

Download Final Report
[Download  PDF: 1.45MB]
 
 
 
General details
Date: 27 November 2006   Investigation status: Completed  
Time: 1800 WST   Investigation level: Complex - click for an explanation of investigation levels  
Location   (show map): 93km N of Perth Airport    
State: Western Australia   Occurrence type: Engine failure or malfunction  
Release date: 24 June 2009   Occurrence category: Incident  
Report status: Final   Highest injury level: None  

Aircraft details

Aircraft details
Aircraft manufacturer Beech Aircraft Corp  
Aircraft model 200  
Aircraft registration VH-XDB  
Serial number BB-533  
Type of operation Air Transport Low Capacity  
Damage to aircraft Minor  
Departure point Mt Hale. WA  
Destination Perth, WA  
Last update 14 November 2018