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Researchers help keep copters flying: USC team plays key role in conducting tests on condition of components [The State, Columbia, S.C.](State (Columbia, SC) Via Acquire Media NewsEdge) Jul. 4--As the 800-horsepower motor revved up, Nicholas Goodman watched dials and charts connected to a series of sensors on a bank of computer screens. Goodman, a USC doctoral candidate from Columbia, was testing how vibration and heat caused by a rotating helicopter drive shaft affect parts. While some joke that a helicopter is nothing more than 10,000 spare parts flying in close formation, the research is serious business. Fostered by the S.C. Army National Guard, the program helps the Army maintain its 6,000-helicopter fleet. The research is necessary because vibrations are a fact of life with helicopters, said Brig. Gen. Les Eisner, S.C. Guard deputy adjutant general. "That's because you have so many rotating components, and they don't necessarily rotate along the same axis," Eisner said. Next year the program will receive a $4 million appropriation from Congress through an earmark sponsored by U.S. Rep. Joe Wilson, R-S.C. The money will be allocated to the S.C. Guard, which contracts with USC to do the research. The program has evolved from techniques used in 1960s and 1970s, when the crew chiefs used grease pencils and long poles to track and balance rotor blades, Eisner said. The crew chief, who is responsible for maintaining the aircraft, would mark the rotors with different colored grease paints. Then, with the aircraft engine operating, the crew chief would walk under the whirling helicopter blades, holding a pole with one end wrapped with a ball of tape. "I looked like a big, giant Q-Tip," Eisner said. The crew chief raised the pole until it touched the blades and he checked to see which colors struck the tape to determine which blade needed adjusting. "Rotor blades got damaged, and it was not very scientific," Eisner said. Research at USC has led to the development of onboard systems that have electronic sensors attached to various parts of a helicopter. The sensors feed data into a processor about the size of a cigar box. The data, which measure vibrations and how they impact components, is downloaded to a laptop computer that the crew chief uses to determine what needs fixing and replacing. The data also are used by engineers to learn why and how parts fail, and how to make them better. In the past, parts were replaced regardless of whether they were about to fail. The maintenance process was not based on science, Eisner said. The program has saved about $1.4 million in parts for just two helicopter models -- the AH-64 Apache and UH-60 Blackhawk, according to a fact sheet posted on the S.C. Guard's Web site. The S.C.-developed devices have saved at least three helicopters in Iraq from destruction because the equipment alerted crews of components that were about to fail, said Lem Grant, a retired chief warrant officer who worked with Eisner in getting the program off the ground. Grant is regarded as an expert on the track and balance of helicopter blades and vibration analysis. Today, onboard devices are installed on about 500 Army helicopters, including all those the S.C. Guard flies. The Guard has about four dozen helicopters in its fleet, including AH-64 Apaches, UH-60 Blackhawks, OH-58 Kiowas and CH-47 Chinooks. The devices are on helicopters flying in combat zones like Iraq and Afghanistan, Eisner said. The USC research team, headed by professor Abdel Bayoumi, works out of a $2.9 million building at Sumter and Catawba streets that opened in 2007. The facility is used to test the tail rotor drive train, main rotor swashplate and tail drive shafts on various models of helicopters. The swashplate controls the helicopter's pitch and how it moves vertically. Research involves more than just the engineering department at USC, Bayoumi said. The Moore School of Business does a cost-benefit analysis that puts a "dollar value on safety," he said. And the School of Public Health is looking at adapting the program to study the human body and how movement affects the limbs, he added. The program employs 15 professors, staffers and students. It has helped showcase the USC mechanical engineering department's expertise in aviation technology, Bayoumi added. "This is also an excellent recruiting tool for high school," Bayoumi said. "We're taking engineering to high school students and saying this is what you could be doing in a few years." USC students benefit because they can see their research used in the field, Bayoumi added. Reach Crumbo at (803) 771-8503. |