Perform an analysis at system level using FTA and FMECA to assess failure of the IGB. This should consider the reliability at the point of dispatch as well as
in flight.
Discussion of system reliability issues and recommendations for changes to design or maintenance tasks in relation to FTA and FMECA Analysis.
Task 2
Your analysis should now be expanded to include the reliability of the Main gearbox lubrication system. Figure 3 shows a Reliability Block Diagram for Loss of
Oil Pressure. This should be integrated into your analysis for the transmission system. Although the analysis should focus on the IGB and Main Gearboxes,
you should consider the effect of reliability on aircraft safety as a whole. For any critical items, you should suggest possible maintenance actions, either
preventative or corrective, and/or any condition monitoring for dormant faults. You will need to justify your analysis with your own research and good
engineering judgment. However, there is no need to develop any aircraft diagrams.
Also discuss the system reliability issues and recommendations for changes to design or maintenance tasks.
Sample Solution
Answer:
For the reliability analysis of IGB and Main Gearboxes, FTA (Fault Tree Analysis) should be used as it provides an effective graphical representation to analyse system level failures. It can also identify the systemic effects of a particular failure on other parts in the system. FMECA (Failure Mode Effect and Criticality Analysis) should also be employed to assess the impact of each component’s failure modes on its performance criteria.
Sample Solution
Answer:
For the reliability analysis of IGB and Main Gearboxes, FTA (Fault Tree Analysis) should be used as it provides an effective graphical representation to analyse system level failures. It can also identify the systemic effects of a particular failure on other parts in the system. FMECA (Failure Mode Effect and Criticality Analysis) should also be employed to assess the impact of each component’s failure modes on its performance criteria.