This paper provides a detailed description of the corrective action validation methods used by the V-22 NAVAIR and Bell-Boeing Team as part of a comprehensive reliability improvement program. The methods include the use of the DoD Army Materiel Systems Analysis Activity (AMSAA) growth model, Weibull analysis, and the Weibayes validation approach. These methods provide the necessary tools to characterize different failure types and develop individual validation test plans. The validation test plans, combined with actual fleet performance data, allows the tracking of validation progress and corrective action effectiveness. This equips the program managers with the proper information to determine if the corrective action implementations need to be accelerated or re-evaluated. It also establishes the expectations to senior management within the program as to the required number of test assets and required test durations needed to statistically validate the corrective action effectiveness.