SACRAMENTO, Calif. --- Aerojet, a GenCorp company, has completed testing of its Advanced Combined Cycle Integrated Inlet (ACCII). The test campaign, performed at the NASA Langley Unitary Plan Wind Tunnel (UPWT) test facility, was the result of a collaboration of government and industry.
Aerojet funded the design and fabrication of the ACCII test article, and the Air Force Research Laboratory in Dayton, OH, invested in both the test facility costs and Aerojet for key analysis efforts.
"This was a great opportunity to work with the Turbine Engine Division, the Aeronautical Sciences Division of the Air Vehicles Directorate, and our industry partners at Aerojet to explore some of the critical design issues in integrating gas turbine and scramjet propulsion cycles into a single highly integrated propulsion system," said Parker Buckley, Chief of the Aerospace Propulsion Division at AFRL. As a collaboration partner, NASA provided test equipment and manpower as well.
The ACCII test program represents the latest in a long history of combined-cycle approaches to manufacture ever faster aircraft. During the 1960s, the venerable SR-71 Blackbird flew to speeds of Mach 3 using a turbo-ramjet combination cycle. Today, aerospace engineers remain challenged with developing technologies for aircraft capable of flight from runway takeoff to Mach 7 (about one- and a-half miles per second) or better, with conventional jet fuels. Concepts have been studied by the U.S. Air Force and NASA -- from applications such as high speed strike / reconnaissance to low cost 'airplane-like' space launch vehicles.
Turbine Based Combined Cycle (TBCC) propulsion has been one accepted standard for these future high speed aircraft designs. TBCC combines the low-speed performance and reliability of turbine engines with the performance and simplicity of a dedicated high-speed Scramjet engine. For years, designers have wrestled with the challenge of how to gracefully transition between the low speed and high speed engines as the vehicle accelerates.
Aerojet's patented ACCII, part of a suite of key combined cycle engine technologies, integrates the needs of the turbine engine and the scramjet engine into one elegant design. "The ACCII inlet provides a true 'combined cycle' approach, allowing smooth transition from low- to high-speed operation through the mission, as if the aircraft had one engine system," said Dick Bregard, Aerojet's vice president of Defense Programs.
The highly instrumented test article was tested for more than three weeks. The broad test program evaluated influences of several flight conditions as well as multiple hardware configurations. The objective of the test campaign -- to provide data for correlation of design methods and analytical tools -- was met successfully. The team will be analyzing the data in more detail throughout the coming weeks. "We have obtained a wealth of data from this program that will help us confidently develop future combined-cycle propulsion applications for the DoD and NASA," said Dr. David Davis, Chief Engineer of Aerojet's Inlet team.
Aerojet is a world-recognized aerospace and defense leader principally serving the missile, space propulsion and armaments markets. GenCorp is a leading technology-based manufacturer of aerospace and defense products and systems with a real estate segment that includes activities related to the entitlement, sale and leasing of the company's excess real estate assets.
Aerojet Demonstrates Combined Cycle Inlet to Enable Hypersonic Flight