An analytical method for predicting life-cycle maintainability labor costs is developed. The purpose of the analytical method is to allow the evaluation of products, based on life-cycle labor costs, early in the design process. The Boeing 737-300/400/500 Bleed Air Control System is used as a test model, and the results of the analysis are compared with historical data for this system. Four prospective design changes to the Bleed Air Control system are analyzed to demonstrate the ability of the analytical method to evaluate and compare differing designs or design changes.