Fundamental Aeronautics Program. The goal of this group is to create technologies and tools needed for airbreathing access to space and other planetary atmospheres.3
Subsonic Fixed Wing Project
The Subsonic Fixed Wing project is the largest project by funding within the Fundamental Aeronautics Program. It has logged millions of flight hours while focusing on two main objectives: (1) to develop prediction and analysis tools in order to reduce uncertainty and (2) to create concepts and technologies to improve noise, emissions, and the performance of the aircraft. These objectives are significant in that they can address demands from NextGen and also improve subsonic air transportation. There are currently 300+ in-house and contracted personnel for the project, with 55+ NASA Research Announcements (NRAs) to academia and businesses as well as various partnerships.4
The stated technical challenge of the Subsonic Fixed Wing project is to explore and develop tools, technologies, and concepts for improved energy efficiency and environmental compatibility for the sustained growth of commercial aviation.5 The environmental challenges include reducing perceived noise and reducing harmful emissions. The efficiency challenges include reducing drag through efficient aerodynamics, reducing weight through new lightweight aircraft structures and propulsion systems, and increasing propulsion system efficiencies. Inherent in all of these challenges is the need to improve tools and analysis techniques.
Tools being developed under the Subsonic Fixed Wing project such as the Fiber Optic Sensing System will advance the ability to determine the health of new lightweight structures, which will improve overall vehicle performance. This capability will be applicable to all flight regimes; however, it has been assigned to the Subsonic Fixed Wing project because it has the greatest opportunity to proceed to flight test under this project.
The planned testing of alternative fuels is also a part of the Subsonic Fixed Wing project even though the new fuels should be usable in rotorcraft and supersonic vehicles. Inter-program collaboration with NASA’s Aviation Safety Program has been conducted in pursuit of new and more robust control system development. The Subsonic Fixed Wing project is also advocating the Planned Cargo Aircraft Precision Formations for Increased Range and Efficiency program. This project is a collaboration with the Defense Advanced Research Projects Agency Formation Flight Program.
Subsonic Rotary Wing Project
Helicopters have been used extensively in the military, and now are being used increasingly in civil operations that include medical evacuation, off-seashore exploration, disaster evacuation, and emergency relief operations. A major inhibition for widespread use of helicopters in the civil market is their life-cycle cost (an order of magnitude higher than that of fixed wing aircraft), which stems from low rotor and propulsion efficiency, high vibratory loads, and unacceptable noise signatures. To increase the structural, aerodynamic, and propulsion efficiencies of the integrated systems, enhancements in rotor aeromechanics in conjunction with variable-speed propulsion system are being explored. A key challenge is to develop robust comprehensive design tools using high-fidelity prediction methodologies.6
The Subsonic Rotary Wing project currently conducts research in support of the Next Generation Air Transportation System and the civil sector. In terms of research, three main areas are currently focused on: efficiency,
3 NASA Fundamental Aeronautics Program, presentation to the National Research Council Committee on NASA’s Aeronautics Flight Research Capabilities, April 20, 2011, Slide 9.
4 NASA Fundamental Aeronautics Program, presentation to the National Research Council Committee on NASA’s Aeronautics Flight Research Capabilities, April 20, 2011, Slides 18-19.
5 NASA Dryden Research Center, “Overview,” presentation to the National Research Council Committee on NASA’s Aeronautics Flight Research Capabilities, April 20, 2011, Slide 116.
6 NASA Fundamental Aeronautics Program, presentation to the National Research Council Committee on NASA’s Aeronautics Flight Research Capabilities, April 20, 2011, Slides 20-21.