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At least 217 records · Page 12

2022 Small Turbine Certification Awardee: Ryse Energy LLC - Americas

To meet the growing demands of the distributed wind market and comply with current U.S. standards, Ryse Energy LLC-Americas (Ryse Energy, formerly Primus Wind Power) plans to update all six products in its AIR Range family of micro wind turbines. A new, more cost-effective circuit board will be paired with other hardware upgrades, advanced control algorithms, and a Bluetooth function that allows users to more easily program and control the turbine. This Competitiveness Improvement Project (CIP) award will fund certification testing of the new circuit board to make sure it meets American National Standards Institute/American Clean Power Association (ANSI/ACP) and UL Federal Communications Commission (FCC) safety and quality standards. Primus Wind Power developed the prototype for the new circuit board with an earlier round of CIP funding, and Primus has received CIP awards supporting other certification and optimization projects.

CIP↗

Formal Approaches to Ensuring the Safety of Space Software

A viewgraph describing formal approaches taken to assure the safety of space software is presented. The topics include: 1) Certifiable Program Generation; 2) Certification Framework; 3) Annotation Generation; 4) Experiments; and 5) Future Work.

Denney, Ewen↗

Bootstrapping Multi-Agent Unmanned Aerial Vehicle (UAV) System Integration Using Ground-Based Assets: Lessons Learned

In support of the Autonomy Teaming and TRAjectories for Complex Trusted Operational Reliability (ATTRACTOR) project, a fleet of unmanned ground vehicles (UGVs) was developed as a test and evaluation (T\&E) platform to reduce system integration gaps between simulation and live flight hardware. While simulation and hardware-in-the-loop bench testing provide adequate environments for preliminary validation, differences in system deployment architecture, software interfaces, and hardware infrastructure increase the risks to safety, property, and the project. Given ATTRACTOR’s goal of establishing a basis of certification of trust and trustworthiness in multi-agent autonomous systems, bridging these gaps was critical to successful project execution and feasibility assessment. In this paper we present the UGV fleet and its role in speeding up system integration, smoothing the transition from simulation to flight, and providing researchers an easy-to-use hardware test bed. An overview of the hardware and software on-board the vehicles is provided along with supporting infrastructure. The system integration process is documented including results in supporting both the overarching design reference mission (DRM) of ATTRACTOR and individual research efforts conducted since the creation of the fleet. Finally, we discuss the practical lessons learned regarding the testing, deployment, and operation of multi-agent autonomous systems.

Matthew P. Vaughan↗

Leveling Arguments: Easier Said Than Done

The aerospace industry’s current desire to rapidly adopt new technologies is inconsistent with the traditional approach to creating new aerospace certification standards. To address this, an FAA-sponsored international Overarching Properties Working Group comprising industry representatives and certifying agencies has introduced the concept of Overarching Properties (OPs). OPs provide a foundation for proposing alternative Means of Compliance (MoC) by demonstrating a product's possession of the Intent, Correctness, and Innocuity properties. Handling criticality levels with the OPs is in its infancy but still required to integrate alternative MoC into the existing aerospace certification infrastructure. This paper examines the impact of criticality levels on the creation and evaluation of OP-related arguments (OPRAs), specifically focusing on the Auxiliary Power Unit (APU) system. The study highlights the need for tailored OPRA creation based on assigned criticality levels and proposes self-assessment techniques to strengthen arguments. This research serves as a stepping stone in exploring criticality levels for OPs and bridging the gap in aerospace certification practices.

argument↗

Validation and Verification of Future Integrated Safety-Critical Systems Operating under Off-Nominal Conditions

Loss of control remains one of the largest contributors to aircraft fatal accidents worldwide. Aircraft loss-of-control accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents and reducing them will require a holistic integrated intervention capability. Future onboard integrated system technologies developed for preventing loss of vehicle control accidents must be able to assure safe operation under the associated off-nominal conditions. The transition of these technologies into the commercial fleet will require their extensive validation and verification (V and V) and ultimate certification. The V and V of complex integrated systems poses major nontrivial technical challenges particularly for safety-critical operation under highly off-nominal conditions associated with aircraft loss-of-control events. This paper summarizes the V and V problem and presents a proposed process that could be applied to complex integrated safety-critical systems developed for preventing aircraft loss-of-control accidents. A summary of recent research accomplishments in this effort is also provided.

Belcastro, Christine M.↗

Commercial Crew Program and the Safety Technical Review Board

The Commercial Crew Program (CCP) is unique to any other program office at NASA. After the agency suffered devastating budget cuts and the Shuttle Program retired, the U.S. gave up its human spaceflight capabilities. Since 2011 the U.S. has been dependent on Russia to transport American astronauts and cargo to the International Space Station (ISS) and back. NASA adapted and formed CCP, which gives private, domestic, aerospace companies unprecedented reign over America's next ride to space. The program began back in 2010 with 5 companies and is now in the final phase of certification with 2 commercial partners. The Commercial Crew Program is made up of 7 divisions, each working rigorously with the commercial providers to complete the certification phase. One of these 7 divisions is Systems Engineering and Integration (SE&I) which is partly comprised of the Safety Technical Review Board (STRB). The STRB is primarily concerned with mitigating improbable, but catastrophic hazards. It does this by identifying, managing, and tracking these hazards in reports. With the STRB being in SE&I, it significantly contributes to the overall certification of the partners' vehicles. After the partners receive agency certification approval, they will have the capability to provide the U.S. with a reliable, safe, and cost-effective means of human spaceflight and cargo transport to the ISS and back.

crew transportation system↗

Quo Vadis Payload Safety?

As we complete the preparations for the fourth Hubble Space Telescope (HST) servicing mission, we note an anniversary approaching: it was 30 years ago in July that the first HST payload safety review panel meeting was held. This, in turn, was just over a year after the very first payload safety review, a Phase 0 review for the Tracking and Data Relay Satellite and its Inertial Upper Stage, held in June of 1977. In adapting a process that had been used in the review and certification of earlier Skylab payloads, National Aeronautics and Space Administration (NASA) engineers sought to preserve the lessons learned in the development of technical payload safety requirements, while creating a new process that would serve the very different needs of the new space shuttle program. Their success in this undertaking is substantiated by the fact that this process and these requirements have proven to be remarkably robust, flexible, and adaptable. Furthermore, the payload safety process has, to date, served us well in the critical mission of safeguarding our astronauts, cosmonauts, and spaceflight participants. Both the technical requirements and their interpretation, as well as the associated process requirements have grown, evolved, been streamlined, and have been adapted to fit multiple programs, including the International Space Station (ISS) program, the Shuttle/Mir program, and most recently the United States Constellation program. From its earliest days, it was anticipated that the payload safety process would be international in scope, and so it has been. European Space Agency (ESA), Japan Aerospace Exploration Agency (JAXA), German Space Agency (DLR), Canadian Space Agency (CSA), Russian Space Agency (RSA), and many additional countries have flown payloads on both the space shuttle and on the ISS. Our close cooperation and long-term working relationships have culminated in the franchising of the payload safety review process itself to our partners in ESA, which in turn will serve as a roadmap for extending the franchise to other Partners.

Fodroci, Michael P.↗

Certification of a Modified Research Public Aircraft

NASA Ames Research Center has several aircraft that have been modified to conduct aeronautical and scientific research. NASA's purpose is to provide research to improve safety of flight and support scientific research for Mission to Planet Earth. Our research and platform aircraft have been modified to fit the needs of the scientific and research programs. Because NASA's aircraft have been modified and operated as public aircraft, certification of airworthiness on many are not current. Some of our aircraft are military aircraft and were never certificated. This paper discusses the process of bringing a modified B200 King Air aircraft certification current to meet Federal Aviation Regulations.

Forsyth, T. J.↗

Conversion-Integration of MSFC Nonlinear Signal Diagnostic Analysis Algorithms for Realtime Execution of MSFC's MPP Prototype System

NASA's advanced propulsion system Small Scale Magnetic Disturbances/Advanced Technology Development (SSME/ATD) has been undergoing extensive flight certification and developmental testing, which involves large numbers of health monitoring measurements. To enhance engine safety and reliability, detailed analysis and evaluation of the measurement signals are mandatory to assess its dynamic characteristics and operational condition. Efficient and reliable signal detection techniques will reduce the risk of catastrophic system failures and expedite the evaluation of both flight and ground test data, and thereby reduce launch turn-around time. During the development of SSME, ASRI participated in the research and development of several advanced non- linear signal diagnostic methods for health monitoring and failure prediction in turbomachinery components. However, due to the intensive computational requirement associated with such advanced analysis tasks, current SSME dynamic data analysis and diagnostic evaluation is performed off-line following flight or ground test with a typical diagnostic turnaround time of one to two days. The objective of MSFC's MPP Prototype System is to eliminate such 'diagnostic lag time' by achieving signal processing and analysis in real-time. Such an on-line diagnostic system can provide sufficient lead time to initiate corrective action and also to enable efficient scheduling of inspection, maintenance and repair activities. The major objective of this project was to convert and implement a number of advanced nonlinear diagnostic DSP algorithms in a format consistent with that required for integration into the Vanderbilt Multigraph Architecture (MGA) Model Based Programming environment. This effort will allow the real-time execution of these algorithms using the MSFC MPP Prototype System. ASRI has completed the software conversion and integration of a sequence of nonlinear signal analysis techniques specified in the SOW for real-time execution on MSFC's MPP Prototype. This report documents and summarizes the results of the contract tasks; provides the complete computer source code; including all FORTRAN/C Utilities; and all other utilities/supporting software libraries that are required for operation.

Jong, Jen-Yi↗

ISS Crew Transportation and Services Requirements Document

The ISS Crew Transportation and Services Requirements Document (CCT-REQ-1130) contains all technical, safety, and crew health medical requirements that are mandatory for achieving a Crew Transportation System Certification that will allow for International Space Station delivery and return of NASA crew and limited cargo. Previously approved on TN23183.

CCT-REQ-1130↗

ISS Crew Transportation and Services Requirements Document

The ISS Crew Transportation and Services Requirements Document (CCT-REQ-1130) contains all technical, safety, and crew health medical requirements that are mandatory for achieving a Crew Transportation System Certification that will allow for International Space Station delivery and return of NASA crew and limited cargo. Previously approved on TN38792.

Commercial Crew Program↗

Hydrogen applications in airport operations: a review using the Port Authority of New York and New Jersey as an illustrative airport system

Airports combine aircraft propulsion, ground operations, stationary power systems, and fuel logistics in ways that make emissions reduction technically and operationally complex. Existing studies often assess hydrogen applications in these areas separately, limiting understanding of the shared infrastructure, safety, and operational constraints that shape airport deployment. This review evaluates hydrogen across three airport-relevant operational domains: aviation propulsion, ground support equipment and vehicles, and stationary power systems. Within aviation propulsion, the review examines sustainable aviation fuel production and hydrogen-powered aircraft as two distinct hydrogen-relevant pathways. The Port Authority of New York and New Jersey is used as an illustrative airport system to relate the literature to a real operating context. Drawing on peer-reviewed studies, technical reports, demonstration projects, and public operational information, the review also includes screening-level calculations of hydrogen demand and potential CO 2 e reductions for selected applications. The findings show that hydrogen's role is highly application-specific. Near-term opportunities are strongest where hydrogen serves as a low-carbon process input, supports selected high-utilization ground equipment, or contributes to resilient stationary power-system configurations. Hydrogen-powered aircraft remain a longer-term option because storage, fueling infrastructure, certification, cost, and NO x management continue to constrain deployment. Across all domains, infrastructure readiness, fuel logistics, safety requirements, and leakage management emerge as recurring determinants of viability. Future research should focus on cross-domain infrastructure planning, comparative assessment of hydrogen against alternative pathways, improved treatment of leakage and non-CO 2 effects, and clearer safety and regulatory frameworks for airport deployment.

08 HYDROGEN↗

Liquid rocket engine flight certification

The following subject areas are covered: current rocket engine certification process; certification issues; engine characteristics; engine design and mission requirements; structural design criteria; structural design factors of safety; component/subsystem testing; system level development tests; certification/qualification tests; observations; and proposed actions/programs.

Richards, Steve↗

FSW Implementation on the Space Shuttle's External Tank

The Friction Stir Welding process developed by The Welding Institute (TWI) has found application throughout the transportation industry. This technique has proven to be a viable joining process for aluminum alloys, producing virtually defect free welds with improved mechanical properties as compared to conventional fusion welding. Lockheed Martin Space Systems - Michoud Operations has been developing this technology for application on aluminum 2219 and 2195 cryogenic tankage since 1995. This effort will come to fruition with implementation on the longitudinal welds of the External Fuel Tank (ET) of the Shuttle. To this end, sub-and full-scale demonstration programs coupled with process development and optimization have been complete. Full size ET tool has been designed, fabricated and are being installed at the Michoud Assembly Facility. Upon completion of the tooling certification and materials allowables testing, production will commence. This implementation will result in increased reliability and safety of flight for the Shuttle.

Hartley, Paula J.↗

Identification of Vehicle Health Assurance Related Trends

Trend analysis in aviation as related to vehicle health management (VHM) was performed by reviewing the most current statistical and prognostics data available from the National Transportation Safety Board (NTSB) accident, the Federal Aviation Administration (FAA) incident, and the NASA Aviation Safety Reporting System (ASRS) incident datasets. In addition, future directions in aviation technology related to VHM research areas were assessed through the Commercial Aviation Safety Team (CAST) Safety Enhancements Reserved for Future Implementations (SERFIs), the National Transportation Safety Board (NTSB) Most-Wanted List and recent open safety recommendations, the National Research Council (NRC) Decadal Survey of Civil Aeronautics, and the Future Aviation Safety Team (FAST) areas of change. Future research direction in the VHM research areas is evidently strong as seen from recent research solicitations from the Naval Air Systems Command (NAVAIR), and VHM-related technologies actively being developed by aviation industry leaders, including GE, Boeing, Airbus, and UTC Aerospace Systems. Given the highly complex VHM systems, modifications can be made in the future so that the Vehicle Systems Safety Technology Project (VSST) technical challenges address inadequate maintenance crew's trainings and skills, and the certification methods of such systems as recommended by the NTSB, NRC, and FAST areas of change.

Phojanamongkolkij, Nipa↗

TPSAS-NF1676L-25778-DND

Testing required to design and certify aircraft structures has increased dramatically with the growth in use of composite materials, and the development time and cost have become an issue as industry looks towards the next generation of aircraft. To help address this challenge, NASA has formed an industry-spanning consortium with the goal of cutting by 30% today's 10-year timeline for developing and certifying composite aircraft structures. This goal is to be achieved by infusing leading edge, physics-based tools to improve the prediction of the response and failure of composite aerospace structures. The plan for the public-private partnership of NASA, the FAA, airframe manufacturers, aircraft engine manufacturers, and several universities is to conduct joint research under the five-year Advanced Composites Program (ACP). The emphasis of the ACP project is the development of damage prediction and non-destructive inspection methods capabilities that are sufficiently reliable to enable a reduction in the element and subcomponent testing necessary for design and certification. ACP also is expected to create rapid design tools to speed preliminary design and improve safety and performance. A critical element of this research concerns the residual strength of postbuckled stiffened panels with impact damage. This presentation will discuss different aspects of ongoing research on the prediction of structural collapse due to skin/stiffener separation. In particular, the presentation will examine issues that must be addressed in the analysis, such as R-curve toughening, delamination migration, bridging, as well as some unexpected effects of ply orientation.

Carlos G Davila↗

Unique safety features and licensing requirements of the NuScale small modular reactor

Small modular reactors (SMR) offer a novel approach to the construction and operation of nuclear power plants. The NuScale VOYGR™ plant uses a simplified SMR design that is based on proven light-water reactor technology with substantial improvements in nuclear safety. It consists of a 250 MWt reactor core housed with other primary system components in an integral reactor pressure vessel surrounded by a steel containment vessel, all of which is immersed in a large pool of water that also serves as the ultimate heat sink. At the core of the NuScale safety case are three primary safety systems: the decay heat removal system, the emergency core cooling system, and the containment. The ability of the NuScale Power Module (NPM) passive safety systems to remove core decay heat for an unlimited duration is demonstrated through analysis of a beyond-design-basis extended loss of AC power with no replenishment of water to the ultimate heat sink or operator actions. The NuScale methodology to evaluate an indefinite loss of AC power uses the proprietary NRELAP5 systems analysis computer code. Analysis results show that the reactor coolant system liquid level above the core is maintained and that containment pressure remains below the vessel design pressure. Once full passive air cooling is established, containment pressure and temperature will decrease over time with decreasing core decay heat. NuScale received standard design approval in September 2020 and design certification in January 2023 for its 50 MWe NPM configured as a 12 module plant. NuScale is currently seeking standard design approval to increase its core power to 250 MWt, nominally 77 MWe per module, in a 6-module plant (VOYGR™-6) configuration. The high-level safety of NuScale’s SMR technology is foundational to a new standard of nuclear power plant resilience.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Assessing High-Intensity Radiated Fields (HIRF) from High-Power Antennas for Air Vehicle Safety

Advanced Air Mobility (AAM), including Urban Air Mobility (UAM), vehicles may be required to meet stringent High-Intensity Radiated Fields (HIRF) certification requirements. HIRF can cause interference and even damage to vehicle systems. A recently proposed map-based avoidance approach can help reduce HIRF protection costs compared to the standard approach. However, it necessitates knowing the locations, frequencies, and transmit powers of high-power antennas within the operating area. This study aims to provide the necessary transmitter data by utilizing regulatory license databases. Using New York City as a representative urban area, fixed transmitter data are presented for AM, FM, TV, satellite uplink, land-mobile radio, microwave link, weather radars, and others. The maximum effective isotropic radiated powers of the antenna are reported. The associated electric field envelopes at 100 feet (30.48 m) distance are compared against the current rotorcraft HIRF standard. The results show that the current standards for protecting vehicles are inadequate. Maps of regions with high HIRF are illustrated. Data for several other cities are also being considered.

HIRF↗