NASA Spinoff

Modeling Tool Advances Rotorcraft Design

Often times, when people think of NASA, they think of space travel. The first “A” in NASA, however, is for “Aeronautics,” and the Agency has always held as one of its tenets to explore, define, and solve issues in aircraft design. Just as often as NASA is associated with space travel, when people hear aeronautics, they often think of airplanes, but part of NASA’s aeronautics program is one of the most advanced rotorcraft design and test programs in the world.

Located at Ames Research Center, the Aeromechanics Branch of the Flight Vehicle Research and Technology Division conducts theoretical and experimental research in support of the U.S. helicopter industry and the U.S. Department of Defense. At this research site, engineers study all aspects of the rotorcraft that directly influence the vehicle’s performance, structural and dynamic responses, external acoustics, vibration, and aeroelastic stability.

They use modern wind tunnels and advanced computational methodologies to calculate fluid dynamics and perform multidisciplinary, comprehensive analyses in the quest to further understand the complete rotorcraft’s operating environment and to develop analytical models to predict aerodynamic, aeroacoustic, and dynamic behavior. The experimental research also seeks to obtain accurate data to validate these analyses, investigate phenomena currently beyond predictive capability, and achieve rapid solutions to flight vehicle problems.

Partnership

Founded in 1979, Continuum Dynamics Inc. (CDI), of Ewing, New Jersey, specializes in advanced engineering services, including fluid dynamic modeling and analysis for aeronautics research. Its clients include government agencies, as well as the aerospace, nuclear, and pharmaceutical industries, and it has been partnering with NASA since its inception.

The company has converted years of NASA-funded research efforts into a variety of commercial products. For example, 1987 and 1992 NASA Small Business Innovation Research (SBIR) grants on helicopter wake modeling resulted in software code used in a blade redesign program for Carson Helicopters, of Perkasie, Pennsylvania, that simultaneously increased the payload of its Sikorsky S-61 helicopter by 2,000 pounds and increased cruise speeds at 10,000 feet by 15 knots.

Follow-on development of this same rotorcraft model, based on 1999 and 2002 NASA SBIR work, resulted in a $24 million revenue increase for Sikorsky Aircraft Corporation, of Stratford, Connecticut, as part of the company’s rotor design efforts.

Altogether, the company has completed a number of SBIR projects with NASA, including early rotorcraft work done through Langley Research Center, but more recently, out of Ames.

This rotorcraft model software code, marketed by CDI as the Comprehensive Hierarchical Aeromechanics Rotorcraft Model (CHARM), is a tool for studying helicopter and tiltrotor unsteady free wake modeling, including distributed and integrated loads, and performance prediction.