AEDC, AFRL collaborate to make advances in hypersonic technology

by Deidre Ortiz
Arnold Engineering Development Complex Public Affairs

8/25/2014 - ARNOLD AIR FORCE BASE, Tenn. -- A highly successful integrated aerodynamic and aerothermal test and analysis of a twin scramjet-powered hypersonic cruise vehicle was completed in the Arnold Engineering Development Complex Hypervelocity Wind Tunnel 9 facility in White Oak, Md.

Researchers and engineers from AEDC and the U.S. Air Force Research Laboratory conducted the testing at Tunnel 9 as part of a scientific research effort program called Hypersonic International Flight Experimentation, or HIFEX.

HIFEX is a joint effort of AFRL and the German Aerospace Centre, or DLR, to advance the maturity of enabling technologies for the realization of a next-generation hypersonic aerospace system.

Douglas Dolvin, AFRL program manager of HIFEX, said the vehicle design tested in Tunnel 9 was unique because it was one that "had never been explored before."

As part of the HIFEX test, the effects of engine unstart on stability and aerodynamic heating of a complex hypersonic vehicle design were evaluated during the wind tunnel test prior to flight experimentation.

The HIFEX program was created to advance the maturity of technologies deemed enabling to the realization of a next-generation hypersonic aerospace systems. The program's goal was to investigate fundamental hypersonic phenomena and characterize the effectiveness of key technologies in a relevant hypersonic environment.

Dolvin explained hypersonic aerospace systems may enable a full spectrum aerospace force with the capability to perform seamless operations that transcend the continuum of air and space domains. Transformational missions currently envisioned include prompt call up and global reach, responsive precision strike and flexible maneuver through anti-access aerial denied regions.

"The research efforts also seek to advance the state-of-the-art in measurements and diagnostic instrumentation," he said. "This has culminated with the [recent] aerodynamic testing of the twin scramjet powered hypersonic cruise vehicle in the Tunnel 9 facility."

AEDC staff was commended for playing an integral role in the testing process, from beginning to end.

"The scientific and test communities worked hand-in-glove like a highly synchronized team," Dolvin said. "The AEDC test component was fully engaged with our HIFEX science component from the early conceptual level definition of the flight vehicle configuration through the development and test of the research model.

"The test director communicated often and effectively with AFRL's principal investigator. Together they formulated a test manifest which was comprehensive enough to capture the most critical aerodynamic phenomena yet responsive to constraints on time and costs."

Dolvin added AEDC's team provided critical support, especially whenever challenges arose.

"They were receptive to inputs from our scientific leads and responsive of the concerns of our on-site representatives," he said. "The knowledge base and experience of the AEDC team was extensive and evident. The high quality optical instruments and the measurements technologies employed, including extensive use of temperature sensitive paints, proved to be instrumental in capturing unsteady aerodynamic phenomena that have never been characterized before and formulating an understanding of complex interactions."

AEDC Commander Col. Raymond Toth received a letter of appreciation from leadership with the AFRL High Speed Systems Division, thanking test engineers Joseph Coblish, U.S. Air Force, and Inna Kurits, with Aerospace Testing Alliance, for their assistance and dedication during the Tunnel 9 test.

"Bottom line is the HIFEX test experience at AEDC White Oak was exceptional," Dolvin said. "The AEDC [Tunnel 9] team has a lot to be proud of out there and I consider myself to be truly blessed to be able to tap into an asset of such significant value to the nation."

John Lafferty, technical director for Tunnel 9, stated he too is pleased with how AEDC and AFRL teams worked together in completing this test and expects the partnership will lead to the success of future tests.

"The collaboration between AFRL and Tunnel 9 is a two-way street," he said. "Becoming aware of the issues and testing needs related to scramjet vehicle testing has allowed us to advance our measurements for this and future tests of its kind. Hopefully this collaboration will continue."

In addition to HIFEX, AEDC has partnered with AFRL to identify, develop and execute several advanced technology programs, such as the Assymetric Scramjet Engine Test and Hypersonic International Flight Research Experimentation programs. AEDC will also be continuing its hypersonic research and test future with AFRL through its hypersonic branch now on site at AEDC.