Materials Mechanical Test Facility
Operations Army Failure Analysis Task
The Army Aviation is partnering with the NASA’s Marshall Space Flight Center’s Materials and Processes Laboratory (MMTF) to meet the helicopter challenges under a NASA Space Act Agreement. Under the agreement, the Army and NASA joined efforts to conduct failure analysis for parts from Army helicopters and unmanned aerial vehicles (UAV).
The MMTF team was called upon to quickly support the failure analysis activities. Parts from Army helicopters are analyzed in the Materials Diagnostic Laboratory using electron microscopy, metallography, chemical analysis and many other failure analysis related techniques.
Failure analysis is an engineering probe that blends scientific and engineering principles. The failure analysis team often received hardware from Apache, Black Hawk, Chinoock and Unmanned Aerial Vehicles that have flown in Iraq and Afghanistan. These parts have to be studied on a microscopic level, because most problems in the metal can’t be seen with the naked eye. The failure analysis engineers used high-powered microscopes and other state-of-the-art analytical equipment to uncover the root causes of the problem, whether it is the way the part was machined, heat-treated or formed and fitted. The failure analysis team also used fractography to characterize the fracture surfaces of the failed parts and find clues that lead to failure.
Over 18 months, the failure analysis group investigated dozens of failure cases and made valuable recommendations to the Army which could prevent failures from re-occurring and extend maintenance cycles. Items analyzed include turbine wheel, engine test drive shaft, swash plate, rotating rings, gears, bolts, transmission, Wankel rotary engines, fuel control pump and many others.
The Army Aviation unit used to send failed parts to the prime contractors, but discovered that the independent analysis provided by the failure analysis team at Marshall identifies problems faster and is more cost efficient. As a result, the program is growing rapidly and MMTF continues to be assigned more analyses of more complicated components.
The Jacobs ESTS Group team received many positive comments, including from George Hanna, a support metallurgist for the Army’s Aviation Engineering Directorate at Redstone, “The long-term expertise of identifying materials failures in the Marshall lab is invaluable to
George Hanna also wrote, “We wish to commend Dr. Po-Shou Chen and his support of the US Army Aviation failure analysis program. He has always been responsive to emergency schedules — he has been available to witness disassemblies within a few hours, and is technically a center of excellence within himself. His solution of the engine test shaft failure was truly outstanding. Not only is his work technically superior but his prompt delivery of well written reports is highly appreciative. We continue to be assigned more analyses of more complicated components because our reports recommend sound solutions.”
Tim Vaughn, chief of the metals Engineering Branch at MSFC, said, “The tests we are conducting in this lab are saving lives. If we can find things to make the parts perform better then we are making it safer for these Army helicopter pilots as well as the soldiers being ferried.