The redesign of the C-17 Globemaster III Auxiliary Power Unit (APU) Exhaust System began out of necessity and ended in success only after solving multiple developmental challenges. The necessity for redesign was driven by both the need to reduce installation costs, reduce fabrication cycle time and improve in-service reliability. The original APU Exhaust System was comprised of 19 major parts that required on-aircraft drilling and custom installation during final assembly. On-aircraft maintenance of every three to six months was required in order to keep the APU system running. The redesign resulted in three parts that were lighter weight, lower cost, easier to install and more reliable. The redesigned system was implemented on the 51st production aircraft with pre-qualified hardware and on the 58th production aircraft with final qualified hardware that has exceeded the project team's expectations.