Tiltrotor Test Rig Team including NFAC receives NASA award

by Raquel March
AEDC Public Affairs

9/24/2013 - ARNOLD AIR FORCE BASE, TENN. -- NASA Ames Research Center recognized the Tiltrotor Test Rig Development Team with a Group Achievement Award at its annual NASA Agency Honor Award ceremony Aug. 29.

The multi-agency TTR Development Team is comprised of NASA Ames Research Center, the U.S. Army and Arnold Engineering Development Complex personnel teaming with Bell Helicopter and Triumph Aerospace Systems. The team received the award "for envisioning and developing the Tiltrotor Test Rig to provide a new national test capability for next generation military and civilian tilt rotor systems."

NASA, the U.S. Army and the U.S. Air Force joined to develop the large scale prop-rotor test system for AEDC's National Full-Scale Aerodynamic Complex, located at NASA Ames Research Center. It is designed to test prop-rotors up to 26 feet in diameter at speeds up to 300 knots. The combination of size and speed is unprecedented and is necessary for research into 21st-century tiltrotors and other advanced rotorcraft concepts. TTR will provide critical data for validation of state-of-the-art design and analysis tools.

The TTR is designed to be used in the 40- by 80-foot and the 80- by 120-foot wind tunnels. TTR is a horizontal axis rig and rotates on the test section turntable to face the rotor into the wind at high speed, or fly edgewise at low speed (100 knots), or at any angle in between.

The TTR is designed to accommodate a variety of rotors. The first rotor planned for testing is taken from the Bell/Agusta 609 vertical take-off and landing (VTOL) aircraft.

For maximum accuracy, rotor forces will be measured by a dedicated balance installed between the gearbox and the rotor. Rotor torque will be measured by an instrumented drive shaft.

Other organizations included in the award are contractor support organizations Jacobs Technology, Inc., AECOM, RS Morris Construction, Monterey Technologies, Inc., Thomson Aerospace & Defense, Lufkin Industries, Kern Steel Fabricators, and ElectroMechanical Engineering Associates.

Summary of TTR design capabilities:

Wind speed - 300 knots axial, 180 knots edgewise
Rotational speed - from 126 to 630 rpm

Rotor thrust - 20,000 lb. steady; 30,000 lb. peak
In-plane force (resultant) - 5000 lb. steady; 10,000 lb. peak

Moment (resultant) - 30,000 ft-lb steady; 60,000 lb. peak
Shaft torque - 48,000 ft-lb. steady; 72,000 lb. peak

Power - 6000 hp max

(Courtesy of NASA)