Commercial aircraft in war
The difference between aircraft for commercial and wartime uses is delineated, but the interchangability between the two is also discussed. Airships in both roles is also presented.
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The difference between aircraft for commercial and wartime uses is delineated, but the interchangability between the two is also discussed. Airships in both roles is also presented.
Single-event upset from heavy ions in measured for advanced commercial microprocessors, comparing upset sensitivity in registers and d-cache for several generations of devices. Multiple-bit upsets and asymmetry in registers upset cross sections are also discussed.
The transfer and commercialization of technology from academic institutions and federal laboratories to private sector firms can provide a stimulus to regional economic development.
Destructive single event effects (DSEE) are a main concern for pioneers attempting to use COTS (commercial-off-the-shelf) devices in space, so a COTS instrument full of such devices is particulary scary.
We show heavy ion test results of a commercial production-level ReRAM. The memory array is robust to bit upsets. However the ReRAM system is vulnerable to SEFIs due to upsets in peripheral circuits, including the sense amplifier.
Single event effect data is presented on the Analog Devices AD7984. The recent heavy-ion test results showcase application-specific results for the commercial part in its intended application.
This presentation describes the accelerating use of Commercial off the Shelf (COTS) parts in space applications. Component reliability and threats in the context of the mission, environment, application, and lifetime. Provides overview of traditional approaches applied to COTS parts in flight applications, and shows challenges and potential paths forward for COTS systems in flight applications it's all about data!
Commercial Crew Program Launch Operations Support
For more than a decade, the Jet Propulsion Laboratory (JPL) and Los Alamos National Laboratory (LANL) have managed a multi-agency funded effort to develop a space reactor power system. The SP-100 Program has developed technologies required for space power systems that can be implemented in the industrial and commercial sectors to improve our competitiveness in the global economy.
The NASA Engineering and Safety Center (NESC) sponsored a Technical Assessment relating to the utilization of commercial-off-the-shelf (COTS) electrical, electronic, and electromechanical (EEE) parts in spaceflight systems at NASA Centers. The assessment had two primary goals. The first was to capture each NASA Centers’ current practices, best practices, lessons learned and Center-proposed recommendations on the use of COTS EEE parts and assemblies in critical ground support equipment (GSE). The second was to provide recommendations on the use of COTS, including a set of current best practices based on the Centers’ current and best practices and the NESC team’s discussions. One key achievement made by the assessment team was the characterization of the term Industry Leading Parts Manufacturers (ILPMs) as parts manufacturer with high volume automatic production facilities and which can provide documented proof of the technology, process and product qualification, and its implementation of the best practices for “zero defects” for parts quality, reliability and workmanship. The assessment concluded with numerous findings, takeaways and recommendations that will be discussed during this presentation.
This paper presents the results of uncertainty modeling of sonic boom noise generation from commercial supersonic transport considering the Spalart-Allmaras (SA) turbulence modeling parameters as well as Mach number, angle of attack and altitude. Sample generation and analysis for this uncertainty model was performed by UQPCE, which is a software package developed at the NASA Langley Research Center. To build the uncertainty model, 42 cases of sonic boom noise calculation were performed. Computation of the ground noise can be briefly summarized in two steps. First, the near field pressure waveforms are sampled from CFD calculation using the NASA Langley’s FUN3D solver. Second, this information is passed to an atmospheric propagation code, sBOOM, which solves an augmented Burger’s equation and simulates how the near field waveforms will change while passing through the atmosphere. The ground signature is further processed to obtain the perceived loudness, PLdB. Having a high spatial resolution near the shockwave in the CFD calculation is critical in sonic boom noise prediction. Because the variation in the input parameters for the current uncertainty quantification (UQ) study is likely to lead to change in shock location, angle and strength, the grid adaptation for shock capturing is independently applied for each condition. The final mesh used in the CFD calculation consists of approximately 420 million cells. The pressure signatures are sampled at three, four and five body lengths away from the aircraft to make sure the three dimensional effects around the aircraft are resolved. The results of the UQ analysis shows that within the three aleatory variables, the angle of attack had the most impact against ground noise, followed by the altitude and the Mach number. Between the two SA model parameters, the Kármán constant (𝜅) was significantly more important than the turbulent Prandtl number (𝜎), but these two parameters were only marginally significant in the overall prediction variance in ground noise. The UQ procedure explained in this paper can be widely applied to other model parameters.
This paper presents the results of uncertainty modeling of sonic boom noise generation from commercial supersonic transport considering the Spalart-Allmaras (SA) turbulence modeling parameters as well as Mach number, angle of attack and altitude. Sample generation and analysis for this uncertainty model was performed by UQPCE, which is a software package developed at the NASA Langley Research Center. To build the uncertainty model, 42 cases of sonic boom noise calculation were performed. Computation of the ground noise can be briefly summarized in two steps. First, the near field pressure waveforms are sampled from CFD calculation using the NASA Langley’s FUN3D solver. Second, this information is passed to an atmospheric propagation code, sBOOM, which solves an augmented Burger’s equation and simulates how the near field waveforms will change while passing through the atmosphere. The ground signature is further processed to obtain the perceived loudness, PLdB. Having a high spatial resolution near the shock wave in the CFD calculation is critical in sonic boom noise prediction. Because the variation in the input parameters for the current uncertainty quantification (UQ) study is likely to lead to change in shock location, angle and strength, the grid adaptation for shock capturing is independently applied for each condition. The final mesh used in the CFD calculation consists of approximately 420 million cells. The pressure signatures are sampled at three, four and five body lengths away from the aircraft to make sure the three dimensional effects around the aircraft are resolved. The results of the UQ analysis shows that within the three aleatory variables, the angle of attack had the most impact against ground noise, followed by the altitude and the Mach number. Between the two SA model parameters, the Kármán constant (𝜅) was significantly more important than the turbulent Prandtl number (𝜎), but these two parameters were only marginally significant in the overall prediction variance in ground noise. The UQ procedure explained in this paper can be widely applied to other model parameters.
This is to present the NESC assessment "Recommendations on Use of Commercial-Off-The-Shelf (COTS) Electrical, Electronic, and Electromechanical (EEE) Parts for NASA Missions" at the Microelectronics Reliability and Qualification Workshop hosted by Aerospace Corporation in February 8-10, 2022. The assessment has two Phases, Phase I on NASA Center current practices on use of COTS and Phase II on DoD and FAA current practices on use of COTS and NESC guidance on COTS selection, application and verification processes. Phase I report was published as NASA/TM−20205011579 and NESC-RP-19-01490 in December 2020. The presentation also includes the scope of the Phase II of the assessment, which is expected to be completed in March-April, 2022.
Most commercial cylindrical 18650 Lithium-Ion (Li-Ion) cells have two internal protective devices: the Positive Temperature Coefficient (PTC) and the Current Interrupt Device (CID). The PTC protects the cells under external short conditions and the CID protects the cells under overcharge conditions. While proven to be effective at the single cell and small-size battery levels, these devices do not always offer protection when used in high-voltage and high-capacity battery designs.
This paper explores the application of established roadmapping approaches in standards planning and roadmap development to support mission assurance objectives. Mission assurance requires proactive planning across multiple domains including technical, schedule, cost, organizational, and policy. The intersection of these domains happens at the enterprise level, and enterprise systems engineering processes can systematically guide mission assurance activities, including development of standards roadmaps. Standards planning and development is a critical contributor to an effective mission assurance strategy, although standards are often developed and adopted reactively. Technology and standards planning is a key Enterprise Process Management activity, as identified by the Systems Engineering Body of Knowledge, and technology and standards roadmaps are strategic tools used to enable that process. Technology roadmapping has proven effective in guiding enterprise architecture and concept design, and standards planning supports enterprise requirements definition and management. However, there are limited methodologies to guide such standards planning activities. The application of technology roadmapping principles to standards planning formalizes the process and establishes a repeatable framework for standards development and integration. The framework development described in this paper fills a methodological gap by adapting proven roadmapping techniques to standards planning. Through a comparison of roadmapping methodologies and a case study analysis, this approach outlines a systematic process for anticipating and planning standards needs. In the case of developing a standards integration roadmap for NASA’s Office of Safety and Mission Assurance (OSMA), technology roadmapping principles were adapted to develop a roadmap framework to allow NASA and OSMA to define an agency-wide standards integration plan for commercial and industry safety and mission assurance standards. The outcome highlights key adaptations required for roadmapping in a standards context and describes the process steps to formalize a standards planning activity. The roadmapping framework adapted for standards development and integration enables more strategic, forward-looking standards planning and allows for better alignment between evolving capabilities and mission assurance requirements. Beyond its application to mission assurance, this methodology can be transferred to other domains requiring standards development, providing a systematic approach that integrates systems engineering principles into policy strategy and decision-making processes.
This fact sheet highlights best practices and guidelines around HVAC and space use for commercial office operators.
A fact sheet of best practices and guidelines around HVAC and space use for commercial office operators.
This fact sheet summarizes resources available to commercial organizations to help them make the business case for and implement energy submetering.