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Recurring Causes of Human Spaceflight Mishaps During Flight Tests and Early Operations

An analysis of recurring causes underlying human spaceflight mishaps that occurred during flight tests and early operations was performed. Eight mishaps from the Apollo, Soyuz, Skylab, Space Shuttle, and Constellation Programs (i.e., the Ares-1X test flight) and early commercial suborbital operations were included in the study. Detailed event analyses were performed for the historical mishaps and aggregate data analyses conducted to identify recurring issues. The nine most frequent issues were inadequate technical controls or risk management practices, incomplete procedures, system design and development issues, inadequate inspection or secondary verification requirements, failures of organizations to learn from previous incidents, inadequate schedule controls, inadequate task analyses or design processes, flaws in the design of organizations, and issues with organizational safety cultures.

Human Spaceflight

iPAS: AES Flight System Technology Maturation for Human Spaceflight

In order to realize the vision of expanding human presence in space, NASA will develop new technologies that can enable future crewed spacecraft to go far beyond Earth orbit. These technologies must be matured to the point that future project managers can accept the risk of incorporating them safely and effectively within integrated spacecraft systems, to satisfy very challenging mission requirements. The technologies must also be applied and managed within an operational context that includes both on-board crew and mission support on Earth. The Advanced Exploration Systems (AES) Program is one part of the NASA strategy to identify and develop key capabilities for human spaceflight, and mature them for future use. To support this initiative, the Integrated Power Avionics and Software (iPAS) environment has been developed that allows engineers, crew, and flight operators to mature promising technologies into applicable capabilities, and to assess the value of these capabilities within a space mission context. This paper describes the development of the integration environment to support technology maturation and risk reduction, and offers examples of technology and mission demonstrations executed to date.

Othon, William L.

Architecting a Human Spaceflight Program

Presentation reviews: (1) What is Architecting, (2) Constellation "Architecture", (3) Human Exploration Architecture (HEFT) Architecting Effort, (4) Forward work in Human Spaceflight Architecting

Human Exploration Architecture (HEFT)

Modeling the Risk of U.S. Offshore Oil & Gas Exploration-Well Drilling, Commercial Nuclear Plants, and Human Spaceflight

Probabilistic Risk Assessment (PRA) has been applied in different industries for many years. Each industry and technology area presents varying challenges and priorities, and the risk models therefore need to be somewhat different. This paper compares aspects of risk modeling of offshore drilling, nuclear plant operation, and human spaceflight. Risk models in all three technology areas have certain high-level similarities: (1) they employ redundancy and diversity in their means to prevent or mitigate risk, including a mix of active and passive systems designed to respond to off-normal evolutions; (2) they are affected by human reliability; (3) their models require consideration of coupling between scenario structure and scenario phenomenology. But in examining the models in more detail, one sees important differences in methodology and emphasis. For purposes of comparison, this paper discusses aspects of a risk model of an offshore drilling operation in the U.S. Gulf of Mexico, focusing on where such a development differs in important ways from models of commercial U.S. nuclear plants and models developed for human spaceflight.

Boyer, Roger L.

Next Steps in Planetary Protection for Human Spaceflight

Planetary protection is defined as: a) the prevention of contamination of extraterrestrial bodies by terrestrial microorganisms, and b) biohazard containment of returned samples from bodies in the Solar System that could harbor life.1 While the majority of interplanetary missions to date have involved robotic exploration, future missions will include human explorers. Current planetary protection requirements do not address the unique challenges associated with human exploration. The purpose of this abstract is to review planetary protection efforts for crewed missions and provide a forward plan for implementing them at the systems level. Article IX of the UN Outer Space Treaty of 1967 provides the definition of planetary protection, outlined above.1 COSPAR holds the international standard in line with this treaty2, while NASA's Planetary Protection Policy (NPD 8020.7G) outlines the U.S. implementation of the COSPAR standard. 3;4 NPI 8020.7 groups future human spaceflight planetary protection studies as follows: 1) microbial monitoring, 2) contamination mitigation and control, and 3) environmental effects. Additionally, a NPI 8020.7 outlines a five-step plan for forward work: 1) a literature review, 2) community inputs, 3) completion of recommended studies, 4) developing a draft NPR, and 5) implementation with NASA teams. The literature review was published in 2016.5 Inputs from the community were gathered at the Planetary Protection Knowledge Gaps for Human Extraterrestrial Missions, held in 2015.6 Johnson and Race (2016) outlined notional requirements and prioritized studies needed before final requirements can be produced. This prior work sets the stage for completing the necessary studies and finalizing planetary protection requirements for human spaceflight. We propose a continuation of the systems engineering approach adopted thus far. The challenges associated with the implementation of notional requirements will be quantified in detailed discussions with internal stakeholders. The status and results of high-priority studies that have been completed since 2016 or are ongoing will be incorporated into discussions with stakeholders. In this way, we plan to bridge the gap between the science behind planetary protection and the engineering development that will implement it, allowing finalized planetary protection requirements to be developed for future human space missions.

Mitchell, Julie

Assessing Engine Hot Fire Data for Human Spaceflight Applications

Development and certification of liquid engine systems for human spaceflight missions requires exhaustive analysis to meet the NASA’s requirements for engine health, reliability, and performance. The techniques used to assess requirement conformance and test-to-test engine health pose many unique challenges including the unusually large scale of data, complex component and system analysis, and rigorous engineering judgement standards. To address these challenges, NASA Marshall Space Flight Center’s Engine Systems branch has developed and maintained a robust software suite and operational processes that satisfy programmatic requirements levied on engines and the 7 Elements of Flight Rationale. Analysis at a systems level includes subsystem assessment of components such as turbomachinery and combustion devices as well as structural and fluid dynamics and transient and steady-state assessment at a systems level. Some of the most important tools to accomplish this analysis are automated script databases, creation of historical and statistical comparisons, and parameters calculated at the full data rate. These tools greatly simplify the crucial processes of anomaly investigation, limit monitoring, health assessment, and timely communication of key conclusions drawn from hot fire testing and flight data analysis.

Data Assessment

Assessing Engine Hot Fire Data for Human Spaceflight Applications

Development and certification of liquid engine systems for human spaceflight missions requires exhaustive analysis to meet the NASA’s requirements for engine health, reliability, and performance. The techniques used to assess requirement conformance and test-to-test engine health pose many unique challenges including the unusually large scale of data, complex component and system analysis, and rigorous engineering judgement standards. To address these challenges, NASA Marshall Space Flight Center’s Engine Systems branch has developed and maintained a robust software suite and operational processes that satisfy programmatic requirements levied on engines and the 7 Elements of Flight Rationale. Analysis at a systems level includes subsystem assessment of components such as turbomachinery and combustion devices as well as structural and fluid dynamics and transient and steady-state assessment at a systems level. Some of the most important tools to accomplish this analysis are automated script databases, creation of historical and statistical comparisons, and parameters calculated at the full data rate. These tools greatly simplify the crucial processes of anomaly investigation, limit monitoring, health assessment, and timely communication of key conclusions drawn from hot fire testing and flight data analysis.

Data Assessment

NASA Human Spaceflight Architecture Team: Lunar Surface Exploration Strategies

NASA s agency wide Human Spaceflight Architecture Team (HAT) has been developing Design Reference Missions (DRMs) to support the ongoing effort to characterize NASA s future human exploration strategy. The DRM design effort includes specific articulations of transportation and surface elements, technologies and operations required to enable future human exploration of various destinations including the moon, Near Earth Asteroids (NEAs) and Mars as well as interim cis-lunar targets. In prior architecture studies, transportation concerns have dominated the analysis. As a result, an effort was made to study the human utilization strategy at each specific destination and the resultant impacts on the overall architecture design. In particular, this paper considers various lunar surface strategies as representative scenarios that could occur in a human lunar return, and demonstrates their alignment with the internationally developed Global Exploration Roadmap (GER).

Mueller, Rob P.

Industry Initiated Core Safety Attributes for Human Spaceflight for the 7th IAASS Conference

Now that the NASA Commercial Crew Program (CCP) is beginning its full certification contract for crew transportation to the International Space Station (ISS), is it time for industry to embrace a minimum set of core safety attributes? Those attributes can then be evolved into an industry-led set of basic safety standards and requirements. After 50 years of human space travel sponsored by governments, there are two basic conditions that now exist within the international space industry. The first, there is enough of a space-faring history to encourage the space industry to design, develop and operate human spaceflight systems without government contracts for anything other than services. Second, industry is capable of defining and enforcing a set of industry-based safety attributes and standards for human spaceflight to low-Earth orbit (LEO). This paper will explore both of these basic conditions with a focus on the safety attributes and standards. In the United States, the Federal Aviation Administration (FAA) is now starting to dialogue with industry about the basic safety principles and attributes needed for potential future regulatory oversight. This process is not yet formalized and will take a number of years once approval is given to move forward. Therefore, throughout the next few years, it is an excellent time and opportunity for industry to collaborate together and develop the core set of attributes and standards. As industry engages and embraces a common set of safety attributes, then government agencies, like the FAA and NASA can use that industry-based product to strengthen their efforts on a safe commercial spaceflight foundation for the future. As the commercial space industry takes the lead role in establishing core safety attributes, and then enforcing those attributes, the entire planet can move away from governmental control of design and development and let industry expand safe and successful space operations in LEO. At that point the governmental agencies can focus on oversight of the industries' defined standards and enforcement for common welfare of the space-faring populous and overall public safety.

crew transportation

Lessons Learned in Architecting Human Spaceflight Programs

This paper discusses the fundamentals of architecting a major human spaceflight program and the lessons that can be learned from Constellation. Constellation is/was NASA's program to implement a new generation of human exploration missions to the moon and beyond. It is/was a tightly-coupled program where a unique set of architectural challenges can be seen and evaluated to better understand how architecting of such systems can be improved upon in the future. While the specific issues discussed in this paper derive from the current Constellation architecture they share threads with previously-crewed systems including Apollo and Shuttle and are likely to be common to any human exploration system or system of significant technical and programmatic complexity.

Muirhead, Brian

An Integrated Reliability and Physics-Based Risk Modeling Approach for Assessing Human Spaceflight Systems

This paper presents an integrated reliability and physics-based risk modeling approach for assessing human spaceflight systems. The approach is demonstrated using an example, end-to-end risk assessment of a generic-crewed space transportation system during a reference mission to the International Space Station. The behavior of the system is modeled using analysis techniques from multiple disciplines in order to properly capture the dynamic time- and state- dependent consequences of failures encountered in different mission phases. We discuss how to combine traditional reliability analyses with Monte Carlo simulation methods and physics-based engineering models to produce loss-of- mission and loss-of-crew risk estimates supporting risk-based decision-making and requirement verification. This approach facilitates risk-informed design by providing more realistic representation of system failures and interactions; identifying key risk-driving sensitivities, dependencies, and assumptions; and tracking multiple figures of merit within a single, responsive assessment framework that can readily incorporate evolving design information throughout system development.

Risk assessment

Contamination Mitigation Strategies for Long Duration Human Spaceflight Missions

Contamination control issues are particularly challenging for long-term human spaceflight and are associated with the search for life, dynamic environmental conditions, human-robotic-environment interaction, sample collection and return, biological processes, waste management, long-term environmental disturbance, etc. These issues impact mission success, human health, planetary protection, and research and discovery. Mitigation and control techniques and strategies may include and integrate long-term environmental monitoring and reporting, contamination control and planetary protection protocols, habitation site design, habitat design, and surface exploration and traverse pathways and area access planning.

enviroment

The Importance of Multilateral Safety Requirements for Human Spaceflight

The International Space Station (ISS) Program initially implemented safety requirements in a series of bilateral agreements between NASA and each International Partner. As the program matured and multilateral processes began to be developed, the differences between these bilaterally agreed requirement sets became more significant. Efforts to develop multilateral safety requirements were hampered for many reasons including assessment of national standards used in the bilateral agreements, requirements baselines for existing contracts, and resource limitations to address requirements changes late in the development and operations phases. To avoid similar requirements issues in the future, international safety requirements need to be developed for human spaceflight. This paper will provide the background of the ISS bilateral Safety and Mission Assurance requirements and processes, describe the activities to develop multilateral safety requirements and processes, and give examples of issues that were encountered. Further, the paper will make recommendations regarding the development of international safety requirements for human spaceflight and the safety topics to be addressed.

Pido, Kelle

Evolution of Flexible Multibody Dynamics for Simulation Applications Supporting Human Spaceflight

During the course of transition from the Space Shuttle and International Space Station programs to the Orion and Journey to Mars exploration programs, a generic flexible multibody dynamics formulation and associated software implementation has evolved to meet an ever changing set of requirements at the NASA Johnson Space Center (JSC). Challenging problems related to large transitional topologies and robotic free-flyer vehicle capture/ release, contact dynamics, and exploration missions concept evaluation through simulation (e.g., asteroid surface operations) have driven this continued development. Coupled with this need is the requirement to oftentimes support human spaceflight operations in real-time. Moreover, it has been desirable to allow even more rapid prototyping of on-orbit manipulator and spacecraft systems, to support less complex infrastructure software for massively integrated simulations, to yield further computational efficiencies, and to take advantage of recent advances and availability of multi-core computing platforms. Since engineering analysis, procedures development, and crew familiarity/training for human spaceflight is fundamental to JSC's charter, there is also a strong desire to share and reuse models in both the non-realtime and real-time domains, with the goal of retaining as much multibody dynamics fidelity as possible. Three specific enhancements are reviewed here: (1) linked list organization to address large transitional topologies, (2) body level model order reduction, and (3) parallel formulation/implementation. This paper provides a detailed overview of these primary updates to JSC's flexible multibody dynamics algorithms as well as a comparison of numerical results to previous formulations and associated software.

Multibody dynamics

NASA Experience with Pogo in Human Spaceflight Vehicles

An overview of more than 45 years of NASA human spaceflight experience is presented with respect to the thrust axis vibration response of liquid fueled rockets known as pogo. A coupled structure and propulsion system instability, pogo can result in the impairment of the astronaut crew, an unplanned engine shutdown, loss of mission, or structural failure. The NASA history begins with the Gemini Program and adaptation of the USAF Titan II ballistic missile as a spacecraft launch vehicle. It continues with the pogo experienced on several Apollo-Saturn flights in both the first and second stages of flight. The defining moment for NASA s subsequent treatment of pogo occurred with the near failure of the second stage on the ascent of the Apollo 13 mission. Since that time NASA has had a strict "no pogo" philosophy that was applied to the development of the Space Shuttle. The "no pogo" philosophy lead to the first vehicle designed to be pogo-free from the beginning and the first development of an engine with an integral pogo suppression system. Now, more than 30 years later, NASA is developing two new launch vehicles, the Ares I crew launch vehicle propelling the Orion crew excursion vehicle, and the Ares V cargo launch vehicle. A new generation of engineers must again exercise NASA s system engineering method for pogo mitigation during design, development and verification.

Larsen, Curtis E.

How To Train Your Dragon (and Vice Versa) – Human Spaceflight Research and The First Commercial Crews

The International Space Station has been an orbiting laboratory for human spaceflight research for over 20 years. NASA’s human research implementation teams have worked to develop, refine, and execute pre-, in-, and post-flight sessions to collect critical research data that will enable future spaceflight missions. The teams have worked closely with the spaceflight vehicle teams, including those for Soyuz and the now retired Space Shuttle vehicles, to successfully conduct this research. As NASA has transitioned to commercial vehicles for transport of crews to the ISS, the implementation teams have expanded their scope to include the SpaceX and upcoming Boeing vehicles. This session will focus on the unique implementation needs for the first available commercial platform, SpaceX. We will identify implementation adjustments made to accommodate the SpaceX Dragon system, including crew training and preflight baseline data collection, inflight operations tied to landing, and postflight planning and crew testing, as well as offer lessons learned from the past three SpaceX long-duration crew missions. Representatives from the Flight Operations Directorate, including the Astronaut Office and the vehicle recovery team, will also provide their perspectives on this new system, and how it affects their work with the human research community. A panel discussion with dedicated time for Q&A will follow.

Pasha Morshedi