The risk of conducting improper maintenance that requires rework to correct inadequacies or collateral damage is addressed below. The focus is on preventive and corrective maintenance during the overhaul period between Shuttle flights. A methodology has been developed for predicting potential maintenance errors, including their impact. The methodology utilizes recorded maintenance data at NASA Kennedy Space Center (KSC) and other locations. Cost-benefit metrics are used to evaluate the effectiveness of candidate changes for risk reduction. Collateral damage to wiring is a significant contributor to wire failures, as well as defective workmanship, operational degradation and improper vendor installation practices. Aging phenomena...