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 left hand fan cowlings, right hand fan cowlings, inlet nose cowlings, left hand fan ducts and acoustic panels, and right hand fan ducts and acoustic panels from The Boeing Corporation for overhaul. Responses are due by May 1, 2017. Delivery of items is required in installments every 75 days from award. Specific quantities of each item are provided. The overhauls are intended for KC-135 aircraft and will be shipped to Tinker Air Force Base. An ombudsman contact is included to field contractor concerns regarding the proposal process.