This document outlines a sole source federal contract opportunity for aircraft engine cowling overhauls. The Air Force Materiel Command Lifecycle Management Center at Tinker Air Force Base is seeking to acquire overhauls of various cowling components for the F108 aircraft engine used in the KC-135 aircraft, including left hand fan cowling, right hand fan cowling, inlet nose cowling, and left and right hand fan duct assemblies. The estimated line item quantities, part numbers, and national stock numbers for each component are specified. Delivery of one item per line is required every 75 days after receipt of order. The solicitation will be issued on March 31, 2017 with a response due date of May 1, 2017. The incumbent and sole source contractor for this opportunity is The Boeing Corporation.