Aviation safety issues and actions
Recommendation issued to: General Electric Usa
|Date issued:||22 February 2000|
|Safety action status:|
|Background:||Why this Recommendation was developed|
The Australian Transport Safety Bureau (formerly the Bureau of
Air Safety Investigation) recommends that the engine manufacturer
General Electric identify the source of the casting defect of the
failed HPT blade.
As a result of investigation into this occurrence, the Bureau simultaneously issues the following recommendation and safety advisory notice:
The Australian Transport Safety Bureau (formerly the Bureau of Air Safety Investigation) recommends that the engine manufacturer General Electric review the adequacy of turbine blade manufacturing process controls to reduce the likelihood of blades containing casting defects being released into service.
The Federal Aviation Administration should note the safety deficiency identified in this document and take appropriate action.
|Date issued:||17 May 2000|
|Response from:||General Electric Usa|
|Action status:||Closed - Accepted|
The loss of rib cross section area from fatigue that initiated
at a casting anomaly, combined with internal surface Intergranular
Oxidation (IGO), reduced the shank cross section area and resulted
in a tensile separation of the Ansett CF6-80A Stage 2 HPTB S/N:
MSCBH987. The loss of load bearing area due to fatigue that
initiated at a casting anomaly is considered to be the primary
cause of the separation.