The goal of this study is to identify breakdown that has an impact on the gas turbine engine's RAM and Six Sigma level in order to assess how well the gas turbine engine performance through the value of RAM (Reliability, Availability, and Maintainability) and Six Sigma. By gathering, compiling, categorizing, and conducting an analysis of data and information on the utilization of gas turbine engines, based on actual data and information, the descriptive analysis method is used to reveal the availability and performance of gas turbine engines. The findings of the RAM and Six Sigma level are examined utilizing the Pareto chart to identify the most impacted breakdown, the Fishbone diagram for root cause analysis, and the five why analysis approach for improvement suggestions. According to research findings, control system failure, VGV system failure, and load distribution problem have an impact on the RAM and Six Sigma level of two gas turbines. The Root cause of the issue is due to a number of factors, including mostly due to technical issues of unreliable old control system and VGV system design, an incorrect maintenance schedule implementation, an incompetent and ignorant of operator or technician to gas turbine engines.