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The Urban Air Mobility (UAM) Market Study is an in-depth study for ODM market leveraging identified key technical barriers to understand community interests and market conditions from all aspects such as regulations, economics, public acceptance, airspace operations and safety.
This chapter summarizes the mission architecture for the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission, ranging from its scientific rationale to the history of its realized conception to itspresent-day organization and management. This volume in the PACE Technical Report series focuses ontrade studies that informed the formulation of the mission in its pre-Phase A (2014-2016; pre-formulation:define a viable and affordable concept) and Phase A (2016-2017; concept and technology development).With that in mind, this chapter serves to introduce the mission by providing: a brief summary of thescience drivers for the mission; a history of the direction of the mission to NASA's Goddard Space Flight Center (GSFC); a synopsis of the mission's and instruments' management and development structures; and a brief description of the primary components and elements that form the foundation ofthe mission, encompassing the major mission segments (space, ground, and science data processing) and their roles in integration, testing, and operations.
NASA's UAS Traffic Management (UTM) project concluded its second flight demonstration activity in late October 2016. This activity demonstrated the capabilities and functionality incorporated into its Technical Capability Level 2 (TCL2) concept, which envisions future operations that are low density, capable of being performed over sparsely populated areas, and allow for a concurrent mix of longer duration, beyond visual-line-of-sight flights and shorter flights within visual-line-of-sight (VLOS). To incorporate these features into a flight demonstration, a scenario-based approach was taken to address different aspects of the TCL2 environment and to meet defined objectives. This paper will describe elements of how the flight activity was conducted and present analyses regarding UTM operations, system messages, and alerting as they pertained to meeting the demonstration objectives and shedding light on research questions and lessons learned.NASA was able to successfully demonstrate complex UTMoperations in a TCL 2 environment in collaboration withindustry partners and the Reno-Stead Airport UAS test range.A scenario-based approach to the demonstration provided arelevant means through which the key elements and objectivesof the test could be captured. Although issues were identifiedthrough the testing and feedback of test participants, theoverall results were in line with the overall UTM objective ofsafely enabling large-scale UAS operations in low altitudeairspace.
NASA's UTM project is conducting research on a traffic management concept for small unmanned aircraft systems (UAS) flying in low altitude, uncontrolled airspace. The project started in 2015 and is developing prototype UTM systems of successively complex technical capability levels (TCL) that are tested in the field. To date TCL levels 1-3 have been tested and TCL 4 will be tested in the summer of 2019. Project results are transferred to the FAA and industry to advance the adoption, implementation, and design standards of future UTM systems.
As future flight crews on long duration deep space missions are expected to operate more autonomously, considerations must be given to onboard capabilities and human-computer teaming that will fortify the safety net traditionally provided by the Mission Control Center. In August 2018, the Human Factors and Behavioral Performance Element of NASA's Human Research Program convened a Technical Interchange Meeting (TIM) on Autonomous Crew Operations at NASA Ames Research Center to address how intelligent technologies can be utilized to augment crew capabilities to support real-time anomaly response. In this paper, we highlight three topic areas discussed at the TIM that have direct implications for future crew anomaly response capabilities: smart structures, cognitive assistants, and manpower.
The Nuclear Power and Propulsion Technical Discipline Team has directed an effort to consider possible improvements to the launch approval process as it relates to fission reactors. To that end, Reference 1 described possible general design criteria and risk criteria for fission reactors. At the time that Reference 1 was completed, it was felt that additional examination of reentry issues was warranted. This paper presents the next step in that examination, which is to accurately describe and frame the problem and suggest safety criteria that might apply to inadvertent reentry. The report includes a discussion of the issues associated with different types of inadvertent reentry, the possible consequences of those events, a review of previous work in the area, security and nonproliferation issues, and options for safety requirements that might be considered. Note that safety requirements can have significant mission implications, e.g., no operation below a certain orbit.
NASA performed research and development of technologies and requirements for traffic management of small Unmanned Aircraft Systems (UAS). In this effort, a small UAS off-nominal situation reporting system was developed to capture information from off-nominal situations to understand their nature and reduce occurrences. This Technical Memorandum (TM) describes the reporting system and analysis of 116 off-nominal situation reports from 352 small UAS operations, which were conducted at two flight test ranges in Summer 2019.
This report documents the 2008 Turbomachinery Technology Assessment and Recommendations of the NASA-led Aerothermodynamics Technical Working Group (TWG). It includes technology review, assessment, and recommendation for future research and development. The areas covered are summarized as follows. Inlet Flow Distortion Sensitivity and Stability, Tip Leakage Flows in High-Pressure Cores, Endwall Contouring, Turbine Tip Flows, Combustor and Cooled-Turbine Interaction, Highly Loaded Low-Pressure Turbines.
Advanced composite structures are increasingly becoming the norm for use in military and commercial aircraft. Many of these structures are in places that are prone to high energy dynamic impact (HEDI) such as a wing or fuselage structures subjected to bird strike or a fan blade out event. Certification testing is expensive and industry currently lacks to the tools to perform reliable certification by analysis or smarter testing. As such, the NASA Advanced Composites Consortium HEDI team was formed with representatives from aerospace original equipment manufacturers, government research laboratories, and academia to advance the state-of-the-art in emerging progressive damage and failure analysis (PDFA) methods in a two phase program. These PDFA approaches have the ability to predict ply-by-ply level damage in composite structures, but to date, have not been thoroughly vetted for HEDI events. In this paper, the technical path that is used in Phase II of the program is presented.
Autonomous in-air wingtip docking of aircraft offers significant opportunity for system level performance gains for numerous aircraft applications. Several of the technical challenges facing wingtip docking of fixed-wing aircraft are addressed in this paper, including: close proximity aerodynamic coupling; mechanisms and operations for robust docking; and relative state estimation methods. A simulation framework considering the aerodynamics, rigid-body dynamics, and vehicle controls is developed and used to perform docking sensitivity studies for a system of two 5.5% scale NASA Generic Transport Model aircraft. Additionally, proof of- concept testing of a candidate docking mechanism designed to move the primary wingtip vortex inboard suggests the viability of such an approach for achieving robust docking.
How can we improve our ability to predict the weather-tomorrow, next week, and into the future? How is the Earth's climate changing? What causes such change? And what are its costs? What can the atmospheres of distant planets teach us about our own planet and its evolution? The Laboratory for Atmospheres is helping to answer these and other scientific questions about our planet and its neighbors. The Laboratory conducts a broad theoretical and experimental research program studying all aspects of the atmospheres of the Earth and other planets, including their structural, dynamical, radiative, and chemical properties, with the overarching goal to provide better understanding and to improve prediction of the Earth's climate. Vigorous research is central to NASA's exploration of the frontiers of knowledge. NASA scientists play a key role in conceiving new space missions, providing mission requirements, and carrying out research to explore the behavior of planetary systems, including, notably, the Earth's. Our Laboratory's scientists also supply outside scientists with technical assistance and scientific data to further investigations not immediately addressed by NASA itself. Laboratory scientists submit competitive research proposals with diverse scientific or technological approaches to NASA and other Federal agencies to acquire research support. The Laboratory management strives to provide a working environment that promotes creativity, competition, and openness. The Laboratory for Atmospheres is a vital participant in NASA's research program. Our Laboratory often has relatively large programs, sizable satellite missions, or observational campaigns that require the cooperative and collaborative efforts of many scientists. We ensure an appropriate balance between our scientists' responsibility for these large collaborative projects and their need for an active individual research agenda. This balance allows members of the Laboratory to continuously improve their scientific credentials. The Laboratory places high importance on promoting and measuring quality in its scientific research. We strive to assure high quality through peer-review funding processes that support approximately 90% of the work in the Laboratory. The overall quality of our scientific efforts is evaluated periodically by committees of advisors from the external scientific community, as detailed in Appendix 2 of this document. Members of the Laboratory interact with the general public to support a wide range of interests in the atmospheric sciences. Among other activities, the Laboratory raises the public's awareness of atmospheric science by presenting public lectures and demonstrations, by making scientific data available to wide audiences, by teaching, and by mentoring students and teachers. Section 6 presents details of the Laboratory's outreach activities during 2002. The Laboratory is also committed to addressing the demographic imbalances that exist today in the atmospheric and space sciences. We must address these imbalances for our field to enjoy the full benefit of all of the Nation's talent. The Laboratory makes substantial efforts to attract new scientists to the fields of atmospheric and space sciences. We strongly encourage the establishment of partnerships with Federal and state agencies that have operational responsibilities to promote the societal application of Earth sciences.
The NASA Unmanned Aircraft Systems (UAS) Traffic Management (UTM) Project executed the fourth and final UTM Technical Capability Level demonstration between May and August 2019. Two Federal Aviation Administration (FAA)-designated UAS test sites managed the range, partners, and operations to meet the requirements set forth by the UTM Project. All stakeholders supported the execution of the flight testing through close collaboration. Results of the demonstration indicate the viability of the UTM concept to manage large scale operations and contingencies in an urban environment. The demonstration also provided insight into key technological gaps that must be addressed before such operations are routine, safe, and efficient. Standardization efforts related to UTM and the industry participants of those efforts can leverage the results and experiences of this flight activity to accelerate and more firmly ground forthcoming standards. The FAA and other regulators will be able to leverage results to inform future rule-making and identify additional gaps that require further analysis.
This white paper has a technical focus meant to provide background to those unfamiliar with the challenges of high temperature electronics, and an understanding of why new surface mission concepts are now viable for Venus and other applications. It describes that, for the first time, high temperature electronics have been developed to enable a paradigm change in extended duration Venus surface exploration. This white paper concentrates on the advances made in Silicon Carbide (SiC) integrated circuit (IC) electronics that have matured to a state where a simple long-life scientific probe is feasible for Venus surface operations. These electronics have been demonstrated for more than a year at 500˚C, 60 days in high-fidelity simulated Venus surface conditions chamber, and have been integrated and demonstrated with prototype long-lived scientific observation sensor technology. Continued maturation of these needed high temperature electronics and sensors is ongoing in the Long-Lived In-Situ Solar System Explorer (LLISSE) project to provide an operational system including sensor control and operation, signal processing, power management, and communications in the early part of the 2020’s. A key focus of this work includes increasing the complexity and decreasing the power consumption of the ICs which will pave the way to enhanced capabilities, such as long-duration Venus seismic measurements. Other IC development efforts include high temperature memory, terrestrial based characterization of volcanic magma, and development of a simple microprocessor. This electronics has also shown to have exceptionally high radiation tolerance, and thus have relevance for a broad range of solar system exploration. Although presently at the level of complexity of 1970-1980 silicon-based electronics, such electronics can enable breakthroughs in Venus planetary exploration akin to 1970s-launched planetary exploration successes (such as Viking and Voyager).
Unmanned Aircraft System (UAS) Traffic Management (UTM) refers to the service-based, cooperative approach to the management of small UAS in the National Airspace System that is safe, scalable, and fair. UTM provides the means to manage the airspace in a complementary manner that does not burden the current air traffic control workforce or infrastructure but allows the Air Navigation Service Provider to maintain its regulatory and operational authority of the airspace. A key feature of UTM is the ability to provide operators the means to strategically deconflict operations from others in the airspace through the digital exchange of information via supporting services. Through this approach, the four-dimensional operation volumes that encompass the intent of operators in a given area are discoverable and can be used for airspace awareness as well as planning conflict free operations that account for and avoid other operations. In certain cases, it is also possible to negotiate volume intersections for shared airspace use without the need to re-plan. In the NASA UTM concept, strategic deconfliction is the first layer of three in the overall conflict management model. The three layers of the conflict management model, which follow the International Civil Aviation Organization’s scheme [ICAO 2005] are: strategic conflict management, separate provision, and collision avoidance. In UTM, the strategic layer mostly occurs prior to departure, but is applicable to en route operations with sufficient planning horizon. The initial requirements for a strategic deconfliction capability within UTM are defined in a NASA publication [Rios 2018]. Within the concept and implementation of service-provided strategic deconfliction is the notion of priority. It is understood that there are instances in which an operation requires a priority designation within the UTM system and special handling accordingly to provide situation awareness and facilitate appropriate responses from other airspace users. Examples of situations requiring priority designation include: when an operator declares an emergency due to problems with the vehicle or its immediate surroundings; operations that are in support of certain organizations (e.g., public safety and first responders); or special missions that also require priority use of airspace (e.g., emergency medical deliveries). UAS Volume Reservations (UVRs) also relate to the topic of priority in the sense that the airspace that the volume encompasses has a different status or classification in which unassociated operations must vacate if inside, or avoid if outside, through strategic deconfliction with the volume. Operations that are specially permitted to access the UVR area are typically assigned priority status given the nature of their mission and their associated credentials. The ability to perform strategic deconfliction, handle certain operations with a priority distinction, and establish UVRs that are communicated throughout the UTM system, is predicated on an architecture that has been established through an evolutionary process in response to close collaboration with stakeholders from government and industry. Another important and influential aspect of these capabilities and architecture is the live, distributed flight tests that have been conducted across the Technical Capability Levels (TCLs) that culminated with a set of complex tests performed as part of TCL4 [Rios 2020]. The TCL4 flight test involved two FAA-designated UAS test sites building teams to collaborate with NASA’s UTM Project on the execution of several detailed, small UAS scenarios in urban environments.
Applications of the Global Positioning System (GPS) to Earth Science are numerous. The International GPS Service (IGS), a federation of government agencies and universities, plays an increasingly critical role in support of GPS-related research and engineering activities. Contributions from the IGS Governing Board and Central Bureau, analysis and data centers, station operators, and others constitute the 2001 / 2002 Technical Reports.
This presentation is intended to show to many future stakeholders to explain the work NASA has planned under the System-Wide Safety project's Complex Autonomous Systems Assurance technical challenge.
Genesis Flight Mechanics Simulation The NASA Engineering and Safety Center (NESC) consolidated and modernized a suite of legacy flight mechanics simulations, including the Flight Analysis and Simulation Tool (FAST), resulting in Genesis, a generic, multi-vehicle, variable-degree-of-freedom flight mechanics simulation for ascent, aerocapture, entry, descent, and landing (A2EDL) trajectory design. Genesis is more flexible, capable, and performant than FAST. It enables trajectory optimization and interactive trajectory generation. Its interoperability with Copernicus, an exo-atmospheric and interplanetary trajectory design tool, facilitates end-to-end trajectory optimization across all mission phases. Genesis is implemented in Julia, a new language for technical computing that combines the ease of use of scripting languages with the run-time performance of compiled languages.
This report documents the goals, organization and outcomes of a Technical Interchange Meeting (TIM) on Computational Materials Approaches for Qualification by Analysis, co-organized by NASA, NIST and the FAA. The TIM was held at NASA Langley Research Center on January 15-16, 2020. Approximately 60 subject matter experts (SMEs) representing 8 aerospace manufacturers, 7 government organizations and 2 universities participated. Expertise of the SMEs spanned the Technology Readiness Level (TRL) scale from the low-to-mid TRL focus of government laboratories and universities to the high TRL perspective of the regulatory organizations and aerospace manufacturers. During this TIM, the future needs of the government regulators and manufacturers motivated the overall discussion and framed the input given by the participants. Hence, the key objectives of the TIM were to understand existing gaps in model-based, e.g., computational materials, processing and performance predictions for aerospace materials and components and forecast how they can be matured to support material, process and part-level qualification and certification (Q&C). The TIM focused on process-intensive metallic materials technologies, including, but not limited to, additive manufacturing. Participation was roughly evenly divided among the processing and performance tracks, suggesting that both topic areas are generally perceived as being both valuable and requiring additional investment. The output of this TIM may be used by both participating and other organizations, in part, as guidance for future national efforts on maturing computational materials capabilities for use in the Q&C of advanced metallic material systems in aerospace applications.