Maintainability Attributes and Comparative Analysis: A Case Study on Aero Engines

The paper makes an attempt to quantify ten maintainability attributes, with a perspective of maintaining a military aero engine. Based on experience and inputs from domain experts, the relative importance of maintainability attributes with respect to each other is computed using a multi-criteria decision-making technique. The attributes are ranked, and the weightage of each of them is computed. The attributes are analysed in an overall maintenance environment and classified under two hierarchical levels. The results so obtained are represented as fuzzy linguistic variables. An approach to evaluate an index to represent the overall maintainability of the aero engine has been developed. Further, a methodology to identify weak maintenance attributes has been formulated. As a practical example, one typical task of maintenance of magnetic chip detection system, which is common to aero engines, is taken up as a case study. Through the evaluation process so established, the maintainability attributes are quantified for the task. The strengths and weakness in maintainability design have been objectively quantified against each attribute for the identified maintenance task.