Anna M. Davis

Date of Award


Document Type


Degree Name

Master of Science


Department of Systems Engineering and Management

First Advisor

Seong-Jong Joo, PhD


In 2007, the Office of the Assistant Secretary of Defense for Sustainment pushed for the need to transition to a Condition Based Maintenance Plus (CBM ) initiative for weapon systems in the U.S. Department of Defense. The CBM initiative can help increase aircraft availability (AA) for the United States Air Force. There are many reasons where AA can be affected but one such issue is engine availability primarily due to oil issues. Within the CBM perspective, this study examines the risk of a jet engine failure due to an oil issue and attempts to predict an engines time until next failure using survival analysis. Predicted engines failure could be used to help pilots, maintainers, repair shops, and system program offices become better equipped to handle an oil issue before it occurs. The results of this study showed that as the engines sorties on wing gradually increased, the risk of failure increased. In addition, this study found that a Weibull model with accelerated failure time was the most suitable model to predict the remaining life of the engine before it failed due to an oil issue. Based on the results, this study developed a field ready estimation tool that could be used by practitioners for predicting engine failures.

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