Failure Analysis of an Air Turbine Starter
Air turbine starters (ATS) are used for the ground start of aircraft engines. This case history describes the failure of an ATS that occurred while starting a developmental gas turbine engine. Fractographic features indicated that few blades of the turbine rotor disc failed in a progressive mode while the remaining blades of the rotor disc indicated failure by overload. The rotor shaft also exhibited features of sudden overload. Analysis of the previous records revealed the observation of sparks developing while the starter was in operation. This indicated possibility of blade tip rubbing which resulted in fatigue crack initiation at the blade root leading to failure.
KeywordsGas turbine starter Fatigue Overload Tip rubbing
The authors express their gratitude to the Defence Research and Development Organization for the support to carry out this work. The authors are thankful to Director, GTRE for giving permission to publish these results. The authors are also grateful to Additional Director, Materials Group for his continuous encouragement. The help extended by the members of Machine Shop and other members of Materials Group is also acknowledged.