Interactive Sonic Boom Display
A supersonic shock wave forms a cone of pressurized air molecules that propagates outward in all directions and extends to the ground. Factors that influence sonic booms include aircraft weight, size, and shape, in addition to its altitude, speed, acceleration and flight path, and weather or atmospheric conditions. NASA's Real-Time Sonic Boom Display takes all these factors into account and enables pilots to control and mitigate sonic boom impacts. <strong>How It Works</strong> Armstrong's technology incorporates 3-dimensional (3D) Earth modeling and inputs of 3D atmospheric data. Central to the innovation is a processor that calculates significant information related to the potential for sonic booms based on an aircraft's specific operation. The processor calculates the sonic boom near a field source based on aircraft flight parameters, then ray traces the sonic boom to a ground location taking into account the near field source, environmental condition data, terrain data, and aircraft information. The processor signature ages the ray trace information to obtain a ground boom footprint and also calculates the ray trace information to obtain Mach cutoff condition altitudes and airspeeds. Prediction data are integrated with a real-time, local-area moving-map display that is capable of displaying the aircraft's currently generated sonic boom footprint at all times. A pilot can choose from a menu of pre-programmed maneuvers such as accelerations, turns, or pushovers and the predicted sonic boom footprint for that maneuver appears on the map display. This allows pilots to select or modify a flight path or parameters to either avoid generating a sonic boom or to place the sonic boom in a specific location. The system also provides pilots with guidance on how to execute a chosen maneuver. <strong>Why It Is Better</strong> No other system exists to manage sonic booms in-flight. NASA's approach is unique in its ability to display in real time the location and intensity of shock waves caused by supersonic aircraft. The system allows pilots to make in-flight adjustments to control the intensity and location of sonic booms via an interactive display that can be integrated into cockpits or flight control rooms. The technology has been in use in Armstrong control rooms and simulators since 2000 and has aided several sonic boom research projects. Aerospace companies have the technological capability to build faster aircraft for overland travel; however, the industry has not yet developed a system to support flight planning and management of sonic booms. The Real-Time Sonic Boom Display fills this need. The capabilities of this cutting-edge technology will help pave the way toward overland supersonic flight, as it is the key to ensuring that speed increases can be accomplished without disturbing population centers.
This technology computes adaptable, fuel/cost-efficient, and flyable descent profiles for one or more aircraft for a particular airport, an arrival route, and a specific period of time. When used by ATC, it can aid the design of arrival procedures and assist the Efficient Descent Advisor (EDA) to realize its full benefits in guiding arrival flights through the transition airspace. When used by airlines, it can potentially reduce the direct operating costs of their arrival flights, particularly for those flying to outstation airports. The algorithms select a descent profile, characterized by a flight-path angle or a descent rate, for one or a group of arrival flights. The minimum-fuel strategy achieves the most fuel benefit but requires communication of the profile in real time (e.g., via data link or voice communication). The other two strategies are less efficient but simpler to implement, and can be used to define more efficient arrival procedures. The algorithm compares fuel and flyability of each trajectory and selects a profile based on aggregated fuel benefits. Three strategies for selecting the descent profile are proposed. The minimum fuel strategy achieves the most fuel benefit but requires communication of the profile in real time such as data link or voice communication. The other two strategies are less efficient but simpler, and can be used in defining an arrival procedure.
Miniaturized High-Speed Modulated X-Ray Source (MXS)
The MXS produces electrons by shining UV light from an LED onto a photocathode material such as magnesium. The electrons are then accelerated across several kV and into a chosen target material; deceleration produces X-rays characteristic of the target. The MXS uses an electron multiplier for high X-ray production efficiency. The MXS is more compact, rugged, and power-efficient than standard X-ray sources. It can be manufactured using commercially available components and 3D printed housing, resulting in a low cost to manufacture. Unlike traditional X-ray sources, the MXS does not require a filament or vacuum and cooling systems. Most importantly, enabling rapid and arbitrary modulation allows using X-rays in the time domain, a new dimension to X-ray applications.
System and Method for Providing a Real Time Audible Message to a Pilot
The invention provides receipt of text messages that are communicated by, or received by, aircraft that are within a selected distance from the inquiring pilots aircraft. This information is filtered by a Pilots Aircraft receiver using a list of Target Words and Phrases (TWP) for which the subject is of concern to the pilot. Messages containing one or more of the selected TWPs are presented in a selected order as text or, alternatively as a verbal message for review by the pilot. Upon receipt of the TWPs, the pilot determines if any action should be taken in order to avoid or minimize delay associated with the information. Communication between the inquiring pilot and any other pilot within the prescribed range, geographic sector, and/or time interval is implemented using a publish and subscribe approach to exchange relevant data. A pilot determines which information to share and with whom and from whom the pilot is interested in receiving information (subscribe). This approach will avoid the radio chatter that often accompanies a party line system. Each such message may be assigned a priority with messages having higher priority being given preference in a message queue. The messages can be filtered and received as coded or encrypted, depending upon a situation or security concerns.
New Wing Design Exponentially Increases Total Aircraft Efficiency
Adverse yaw, present in current aircraft design, is the adverse horizontal movement around a vertical axis of an aircraft; the yaw opposes the direction of a turn. As an aircraft turns, differential drag of the left and right wings while banking contributes to aircraft yaw. Proverse yaw—yawing in the same direction as a turn—would optimize aircraft performance. Initial results from flight experiments at Armstrong demonstrated that this wing design unequivocally established proverse yaw. This wing design further reduces drag due to lift at the same time. <strong>How It Works</strong> The Armstrong team (supported by a large contingent of NASA Aeronautics Academy interns) built upon the 1933 research of the German engineer Ludwig Prandtl to design and validate a scale model of a non-elliptical loaded wing that reduces drag and increases efficiency. The key to the innovation is reducing the drag of the wing through use of an alternative bell-shaped spanload, as opposed to the conventional elliptical spanload. To achieve the bell spanload, designers used a sharply tapered wing, with 12 percent less wing area than the comparable elliptical spanload wing. The new wing has 22 percent more span and 11 percent less area, resulting in an immediate 12 percent drag reduction. Furthermore, using twist to achieve the bell spanload produces induced thrust at the wing tips, and this forward thrust increases when lift is increased at the wingtips for roll control. The result is that the aircraft rolls and yaws in the same direction as a turn, eliminating the need for a vertical tail. When combined with a blended-wing body, this approach maximizes aerodynamic performance, minimizes weight, and optimizes flight control. <strong>Why It Is Better</strong> Conventional aircraft make use of elliptical loaded wings to minimize drag. However, achieving aircraft stability and control in conventional elliptical wings produces a strong adverse yaw component in roll control (i.e., the aircraft will yaw the opposite direction with application of roll control). Therefore, a vertical tail or some other method of direct yaw control is required, such as split elevons for use as drag rudders. The use of elliptical wings also results in a suboptimal amount of structure to carry the integrated wing bending moment. Adopting the bell-shaped spanload change results in an immediate 12 percent drag reduction. In addition, optimization of the overall aircraft configuration is projected to achieve additional significant overall performance increases.
Lightweight Energy Absorbing Composite Airframe Subfloor
This technology's conusoidal geometry is based on right-side-up and up-side down halfcones placed in an alternating and repeating pattern. This geometry combines a simple cone design with a sinusoidal beam geometry to create a structure that utilizes the advantages of both designs. The first major advantage of the conusoidal design is it provides crush trigger mechanisms due to dissimilar conical radii dimensions on the crash front. This is consistent with many energy absorbing (EA) designs which contain trigger mechanisms to limit the peak crush load and achieve acceptable crush initiation behavior. Second, because the conical walls are formed at an inward angle relative to the geometric centerline of each cone, the crushing is self-stabilizing. Finally, as the graphic below shows, the dissimilar radii create an inherent forward leaning angle, which offers advantages when examining loading conditions with a multi-axial component of loading. Many potential materials and layup combinations were candidates for the fabrication of the conusoidal EA. Specific interest was given to both the conventional and hybrid families of woven fabrics. Hybrid material systems consisting of carbon and aramid fibers were considered for use since they would potentially contain desirable characteristics that would serve as an advantage for energy absorbing performance. These material systems would offer both stiffness characteristics from the carbon fibers and deformation/ductility characteristics from the aramid fibers.
Wind-tunnel Force Measurement Calibration System
During wind-tunnel testing, a balance is used to obtain high-precision measurements of the aerodynamic loads on an aircraft model. Most balance calibrations are conducted in a laboratory environment, where most of the nuisance variables, such as temperature, electrical noise, vibrations, etc., can be controlled. When the instrumentation is transferred to the test environment, the nuisance variables change as well as the behavior of the system. To ensure that the calibration of the balance is still valid for the change in environment, validation checks are conducted in the wind tunnel. Currently, multi-component test environment validation checks are mechanically complex, introduce uncertainties in the applied loads, and are time consuming. This technology is designed to address the challenge of evaluating wind-tunnel model system performance during test preparation activities. ILS is based on the force-vector concept where a single deadweight load is used to apply up to six loads simultaneously through changing the orientation of the wind-tunnel model system relative to gravity. As the orientation of the force balance changes relative to gravity, the applied load vector that is produced imparts varying load combinations and magnitudes. During typical force-balance checkout, multiple-component loads are not applied although researchers and wind-tunnel customers expect these types of complex loadings during testing. In addition, axial force (aerodynamic drag), which is the aerodynamic component of highest interest, is rarely checked during the checkout process. ILS permits a more robust evaluation of the laboratory calibration during checkout as opposed to current approaches that are used. Furthermore, since the ILS uses a single load and the design is mechanically simpler than the current checkout hardware, many sources of systematic error are removed from the process.
information technology and software
Traffic Aware Strategic Aircrew Requests (TASAR)
The NASA software application developed under the TASAR project is called the Traffic Aware Planner (TAP). TAP automatically monitors for flight optimization opportunities in the form of lateral and/or vertical trajectory changes. Surveillance data of nearby aircraft, using ADS-B IN technology, are processed to evaluate and avoid possible conflicts resulting from requested changes in the trajectory. TAP also leverages real-time connectivity to external information sources, if available, of operational data relating to winds, weather, restricted airspace, etc., to produce the most acceptable and beneficial trajectory-change solutions available at the time. The software application is designed for installation on low-cost Electronic Flight Bags that provide read-only access to avionics data. The user interface is also compatible with the popular iPad. FAA certification and operational approval requirements are expected to be minimal for this non-safety-critical flight-efficiency application, reducing implementation cost and accelerating adoption by the airspace user community. Awarded "2016 NASA Software of the Year"
mechanical and fluid systems
Smallsat attitude control and energy storage
Reaction spheres technology operate on a physics similar to reaction wheels, which by the conservation of angular momentum uses a rotating flywheel to spin a body in the opposite direction. Sphere systems that utilize magnetic torqueing rather than mechanical are also smaller, are more reliable, have low friction losses, and have improved lifetime performance. The proposed reaction sphere provides improved performance over traditional wheels and satisfies the push for component miniaturization, increased pointing accuracy, and power efficiency on CubeSats. Primary aims are to develop a low-friction method to contain a sphere in spaceflight and determine the feasibility of on-orbit momentum storage to supplement battery power. With appropriate placement of permanent magnets, the sphere systems can generate relatively equal value of momentum and torques for any spin axis. This sphere at any speed, produces more momentum than the wheels, resulting in faster attitude stability.
Compact, Lightweight, CMC-Based Acoustic Liner
NASA researchers are extending an existing oxide/oxide CMC sandwich structure concept that provides mono-tonal noise reduction. That oxide/oxide CMC has a density of about 2.8 g/cc versus the 8.4 g/cc density of a metallic liner made of IN625, thus offering the potential for component weight reduction. The composites have good high-temperature strength and oxidation resistance, allowing them to perform as core liners at temperatures up to 1000°C (1832°F). NASA's innovation uses cells of different lengths or effective lengths within a compact CMC-based liner to achieve broadband noise reduction. NASA has been able to optimize the performance of the proposed acoustic liner by using improved design tools that help reduce noise over a specified frequency range. One such improvement stems from the enhanced understanding of variable-depth liners, including the benefits of alternate channel shapes/designs (curved, bent, etc.). These new designs have opened the door for CMC-based acoustic liners to offer core engine noise reduction in a lighter, more compact package. As a first step toward demonstrating advanced concepts, an oxide/oxide CMC acoustic testing article with different channel lengths was tested. Bulk absorbers could also be used, either in conjunction with or in place of the liners internal chambers, to reduce noise further if desired.