Rapid Response Flight Test on MH-47G Engine Exhaust Suppressor

This paper describes the response to a severe airframe cracking issue which impacted the 160th Special Operations Aviation Regiment (Airborne) (SOAR(A)) MH-47G Chinook fleet. A myriad of sophisticated analysis tools and techniques were applied to this problem to include: scale model wind tunnel testing, joint time frequency analysis, and rapid experimental prototyping. To the Test Team's surprise, initial theories based on wind tunnel testing were disproved by flight testing, and it was the testing of actual mission representative hardware / flight conditions that uncovered the root cause of cracking. This paper outlines the preliminary analysis and ensuing flight test and offers some lessons learned in the process.