Leveraging the Surplus Market to Reduce Costs How can spare parts be used more efficiently and effectively by increasing cooperation within the industry and sharing between operators? With the increasing level of complexity in parts data, how can we proceed to better optimize stock with IT support? Can PMAs be used on 3rd run and subsequent engine shop visits? Are DERs and PMAs really having a high impact on values? If so, is it constant over the lifecycle of the asset? What makes a good used part?