Aviation safety investigations & reports

In-flight engine failure and shut down; 148 km NNW Launceston TAS

Investigation number:
200501189
Status: Completed
Investigation completed

Summary

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Boeing Company 717-200 aircraft, VH-VQB, was operating a scheduled passenger service from Launceston, Tasmania to Melbourne, Victoria when the right (number-2) engine failed during the climb to cruise altitude.  After securing the failed engine, the flight crew declared a PAN condition and continued the flight to Melbourne where the aircraft landed uneventfully.

Examination of the failed BR715-A1-30 engine by the operator’s maintenance staff and subsequently by the engine manufacturer under the supervision of a representative of the German Federal Bureau of Aircraft Accident Investigation (BFU), confirmed a mechanical failure within the engine high-pressure turbine section.  The failure was traced to the fatigue fracture and loss of a single stage-1 high-pressure turbine blade, with the resultant cascading mechanical damage to the downstream turbine elements and the initiation of a high-temperature titanium metal fire within the high-pressure compressor stages.

Characteristics of the failed turbine blade fracture surfaces indicated that a high-cycle (vibratory) loading environment had contributed to the development of the fatigue cracking that led to the blade loss.  A significant contributor to the magnitude of the vibratory blade loading was the extent of trailing edge erosion and metal loss exhibited by the turbine nozzle guide vanes (NGV).  Those vanes progressively degrade in service due to the effects of oxidation and thermal cycling and are typically removed from service once the erosion and damage exceeds serviceable limits.  While not evident during the examination, it was suspected that pre-existing blade mechanical damage may have acted in concert with the vibratory loads to initiate cracking.

Following the investigation, the manufacturer implemented several changes to the maintenance regime for the BR715 engine, including monitoring of the P30 engine parameter that reflects the level of NGV erosion and the mandatory replacement of eroded NGV segments that may otherwise have been repaired and returned to service.

Download Final Report
[Download  PDF: 3.24MB]
 
 
 
General details
Date: 18 March 2005   Investigation status: Completed  
Time: 22:51    
Location   (show map): 148 km NNW Launceston, Aero.    
State: Tasmania   Occurrence type: Engine failure or malfunction  
Release date: 27 November 2006   Occurrence class: Technical  
Report status: Final   Occurrence category: Incident  
  Highest injury level: None  

Aircraft details

Aircraft details
Aircraft manufacturer The Boeing Company  
Aircraft model 717  
Aircraft registration VH-VQB  
Serial number 55002  
Type of operation Air Transport High Capacity  
Damage to aircraft Minor  
Departure point Launceston, Tas.  
Destination Melbourne, Vic.  
Last update 16 February 2016