NFAC team tests cutting-edge technology on UH-60 rotor system

  • Published
  • By Philip Lorenz III
  • AEDC/PA
Arnold Air Force Base, Tenn. --  A team at Arnold Engineering Development Center's (AEDC) National Full-Scale Aerodynamics Complex (NFAC) at Moffett Field, Calif., recently concluded high-power, top priority testing on a full-scale four-bladed UH-60 Blackhawk rotor system in the facility's 40-by-80-foot wind tunnel. 

The primary purpose of the testing was to evaluate an individual blade control (IBC) system for its ability to reduce noise, vibration and improve the performance of the rotor system. 

The Black Hawk, manufactured by Sikorsky Aircraft, is the Army's twin-engine and medium-lift utility helicopter used for air assault, air cavalry and aero medical evacuation units. 

"This was the culmination of a collaborative wind tunnel test program between NASA, the U.S. Army, Sikorsky Aircraft and ZF Luftfahrttechnik GmbH (ZFL) to demonstrate the benefits of IBC for a UH-60 rotor," said Tom Norman, a project engineer with NASA Ames. "All major test objectives were met, allowing for the evaluation of IBC effects on power, noise, vibration, loads and flight characteristics. In addition, the ability of the IBC technology to provide in-flight tuning and reconfiguration was demonstrated." 

ZFL is a German company that supplied the actuators that provided the pitch control of the rotor blades. 

Norman said he was pleased with the test results. 

"The data quality was high for the primary data channels, although we're still evaluating the secondary channels," he said. "NASA and its partners will now begin a process of reviewing and analyzing the data in preparation for publication. Subsequently the data will be used to evaluate and improve rotorcraft predictive tools." 

Jeff Johnson, Arnold's test engineering group lead at NFAC, said, it is important to recognize the amount of preparation and work that goes into a rotor test like the one just completed. 

"The LRTA (Large Rotor Test Apparatus) has been in the tunnel for more than nine months, which is a bit unusual," he explained. "Part of the reason for that is because we were learning - training a new team and developing a new data system. So, there are growing pains that won't be there the next time we do a test like this with this test article. Also, performing a thorough and accurate checkout of all the measurements is critical for safety-of-flight and data quality, so we have to take the time to do it right."

"A lot of people and systems have to come together to make one of these tests work," Johnson added, "so it's a huge team effort - the NFAC team really stepped up to make this test a success."