Jon Holladay

John F. Kennedy set the tone for NASA’s culture in 1961 during his famous speech on going to the Moon, “We choose to go to the Moon not because it’s easy, but because it’s hard; because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone...” That culture has never faded, even across NASA’s diverse spectrum of missions. The continuous challenge to do what is hard or near… Show more

John F. Kennedy set the tone for NASA’s culture in 1961 during his famous speech on going to the Moon, “We choose to go to the Moon not because it’s easy, but because it’s hard; because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone...” That culture has never faded, even across NASA’s diverse spectrum of missions. The continuous challenge to do what is hard or near impossible includes the requirement for innovation. Innovation is the importance of what we do, but also how we do it. With a goal of improving the way NASA’s workforce engineers its systems, the Systems Engineering (SE) Technical Discipline Team (TDT) has partnered with numerous facets of the NASA workforce to better enable innovation in how we work. Over the past year, three diverse teams made progress toward that goal by looking at the way we levy technical standards, improving understanding and integrated risk (cost, schedule, and technical), reducing project risk by better management of mass growth, and moving SE into the model based digital domain. A brief summary of each team’s efforts follows. Show less

Engineers from every technical discipline provide the critical subsystems necessary for NASA’s spaceflight missions. But ensuring these integrated subsystems will operate seamlessly at lift-off and successfully transport their payloads to their destinations requires the input of another technical discipline, systems engineering.

The primary motivations for establishing the MBSE Pathfinder were to advance the Agency's applications of MBSE and capture lessons-learned to inform the next steps. The MBSE Pathfinder had four teams working in parallel for eight months on different topics of interest to NASA. The teams were encouraged to learn, and use creativity and innovation in their system modeling. The results were captured via reports, webinars, and a knowledge capture meeting. The approach taken for the MBSE Pathfinder… Show more

The primary motivations for establishing the MBSE Pathfinder were to advance the Agency's applications of MBSE and capture lessons-learned to inform the next steps. The MBSE Pathfinder had four teams working in parallel for eight months on different topics of interest to NASA. The teams were encouraged to learn, and use creativity and innovation in their system modeling. The results were captured via reports, webinars, and a knowledge capture meeting. The approach taken for the MBSE Pathfinder was very successful in providing a number of lessons-learned for NASA and for other organizations considering MBSE or pathfinder efforts, and in building a very strong and collaborative user community. Show less

Serve on advisory committee for DoD and NASA annual workshop to improve Systems Engineering via more robust and intentional application of analytical capabilities to the design, development test and evaluation or aeronautical and aerospace systems and missions. Moderated panel focused on integration of decision analytics and next generation digital tools for data visualization.

Invited to provide government perspective on subject panel. Also moderated panel on different applications of SE within broad spectrum of NASA missions from Aeronautics, Science, Human Spaceflight and Technology.

... in a manner that honors the three driving objectives of safety, affordability, and sustainability, SLS development leverages existing NASA spacefight assets, infrastructure, and workforce, and a commonality- based approach for evolution. Using proven legacy hardware and infrastructure with a heritage of success helps keep NASA’s exploration launch vehicle program safe and affordable while also expediting delivery of a near-term capability. By planning for enhancements based on… Show more

... in a manner that honors the three driving objectives of safety, affordability, and sustainability, SLS development leverages existing NASA spacefight assets, infrastructure, and workforce, and a commonality- based approach for evolution. Using proven legacy hardware and infrastructure with a heritage of success helps keep NASA’s exploration launch vehicle program safe and affordable while also expediting delivery of a near-term capability. By planning for enhancements based on commonalities, SLS will evolve into the most powerful launch vehicle ever fown in a manner that is affordable and sustainable for the nation. Show less

The Space Launch System (SLS) is envisioned as a heavy-lift vehicle that will provide the foundation for future beyond-low-Earth orbit (LEO) exploration missions. Previous studies have been performed to determine the optimal configuration for the SLS and the applicability of commercial off-the-shelf in-space stages for Earth departure. Currently, NASA is analyzing the concept of an Exploration Upper Stage (EUS) that will provide LEO insertion and Earth departure burns. This paper explores… Show more

The Space Launch System (SLS) is envisioned as a heavy-lift vehicle that will provide the foundation for future beyond-low-Earth orbit (LEO) exploration missions. Previous studies have been performed to determine the optimal configuration for the SLS and the applicability of commercial off-the-shelf in-space stages for Earth departure. Currently, NASA is analyzing the concept of an Exploration Upper Stage (EUS) that will provide LEO insertion and Earth departure burns. This paper explores candidate in-space stages based on the EUS design for a wide range of beyond LEO missions. Mission payloads will range from small robotic systems up to human systems with deep space habitats and landers. Mission destinations will include cislunar space, Mars, Jupiter, and Saturn. Show less

Overview of SLS Dual Use Upper Stage baseline.

Subject Matter Expert Consultant, Architecture Study Team.

From Wikipedia, "According to a paper written by Dennis Tito, "the mission would require no maneuvers except small course corrections after a trans-Martian injection burn, [and] would allow no aborts. ... [It will] use low Earth orbit launch and crewed-spacecraft technology, outfitted for the long duration of a flight to Mars." The mission was a free return human mission to Mars and back.

NASA Marshall Space Flight Center (MSFC) in support of Exploration Systems Directorate (ESD) in Washington, DC has been developing approaches to track affordability across multiple Programs. The first step is to ensure a common definition of affordability: the discipline to bear cost in meeting a budget with margin over the life of the program. The second step is to infuse responsibility and accountability for affordability into all levels of the implementing organization since affordability is… Show more

NASA Marshall Space Flight Center (MSFC) in support of Exploration Systems Directorate (ESD) in Washington, DC has been developing approaches to track affordability across multiple Programs. The first step is to ensure a common definition of affordability: the discipline to bear cost in meeting a budget with margin over the life of the program. The second step is to infuse responsibility and accountability for affordability into all levels of the implementing organization since affordability is no single person’s job; it is everyone’s job. The third step is to use existing data to identify common affordability elements organized by configuration (vehicle/facility), cost, schedule, and risk. The fourth step is to analyze and trend this affordability data using an affordability dashboard to provide status, measures, and trends for ESD and Program level of affordability tracking. This paper will provide examples of how regular application of this approach supports affordable and therefore sustainable human space exploration architecture. Show less

Shows the high performing in-space stage options (new and existing) and appropriate mission design path that captures meaningful mission scenarios in the near-term. These include an uncrewed and crewed lunar flyby and large mass, direct transfer Jupiter/Europa science mission with the Delta Cryogenic Second Stage and Block 1 SLS.

Derived top-level approach to engine-out philosophy for a heavy lift launch vehicle based on an historical assessment of launch vehicle capabilities. Methodology not intended to present best path forward, but instead provides three parameters for assessment of a particular vehicle: Reliability (Loss of Mission & Loss of Crew), vehicle performance and cost.

High level trade space capture of the RAC Team 2 evaluation of high-performing, LOX/Hydrocarbon vehicles. Engine options included F-1A-class gas generator cycle engines, modular approaches to oxygen-rich staged combustion engines, foreign engine alternatives, and combinations of existing & planned domestic engine options.

Overview of the assessed technology options for the chemical LOX/LH2 propellant-based approach for Mars mission design. These technologies include automated rendezvous & docking, in-space cryogenic propellant transfer, passive & active cryogenic fluid management techniques, low mass micrometeoroid & orbital debris shielding techniques, and large, lightweight, multi-use shrouds.

Discusses the architecture constructed from both a Nuclear-Thermal propulsion & Chemical, LOX/LH2 propulsion perspective, but focuses on the elements required to be delivered by a heavy-lift vehicle. Determines the potential for a reduction in the number of launches through the use of cryogenic propellant transfer, and finally shows the potential to transition to a commercial in-space propellant acquisition model with the heavy-lift vehicle only delivering the large mass components.

The rst designs for a heavy lift capability that would eventually be named Ares V were studied during ESAS, which began in 2005.3 From ESAS to the concept approved during LCCR as the Ares V MCR POD concept, NASA studied more than 1,700 con gurations of the Ares V. Following the LCCR POD, several trade studies were performed that resulted in an updated POD known as the Phase A-Cycle 3D (PA-C3D) concept. This section will summarize the evolution of Ares V from the ESAS trades up to the PA-C3D… Show more

The rst designs for a heavy lift capability that would eventually be named Ares V were studied during ESAS, which began in 2005.3 From ESAS to the concept approved during LCCR as the Ares V MCR POD concept, NASA studied more than 1,700 con gurations of the Ares V. Following the LCCR POD, several trade studies were performed that resulted in an updated POD known as the Phase A-Cycle 3D (PA-C3D) concept. This section will summarize the evolution of Ares V from the ESAS trades up to the PA-C3D concept, including the 51.00.39 concept that served as the entry point to the LCCR trade study. An overview of the Ares V development his- tory is shown in gure 3, including the LCCR trade space options and recommended POD concept approved by CxP, both of which will be detailed in later sections. A description of the major trades leading to the pre-51.00.39 concept follows. Show less

With over 4 yr of increased knowledge of the Ares V concept, an evolved vehicle con gu- ration, and established Ares V element teams in place for almost a year-and-a-half, the Ares V team assessed the capability offered by Ares V against the Mars Design Reference Mission (DRM) established in the Exploration Systems Architecture Study (ESAS)1 and later the Constellation Architecture Requirements Document (CARD). This provided valuable insight into the available performance capability to… Show more

With over 4 yr of increased knowledge of the Ares V concept, an evolved vehicle con gu- ration, and established Ares V element teams in place for almost a year-and-a-half, the Ares V team assessed the capability offered by Ares V against the Mars Design Reference Mission (DRM) established in the Exploration Systems Architecture Study (ESAS)1 and later the Constellation Architecture Requirements Document (CARD). This provided valuable insight into the available performance capability to low-Earth-orbit (LEO) and the available performance growth options available; the required functionality to launch, maintain, and assemble a Mars transfer vehicle (MTV) in LEO; and the capability of the Earth Departure Stage (EDS) to possibly perform the trans-Mars injection (TMI) maneuver if required. In addition, it allowed the Ares V team to assess the ability of the vehicle to be built, stored, transported, and launched at the required rate for the Mars architecture. Show less

NASA defined and began implementing plans for integrated ground and flight testing necessary to achieve the first human launch of Ares I. The individual Ares I flight hardware elements: the first stage five segment booster (FSB), upper stage, and J-2X upper stage engine, will undergo extensive development, qualification, and certification testing prior to flight. Key integrated system tests include the Main Propulsion Test Article (MPTA), acceptance tests of the integrated upper stage and upper… Show more

NASA defined and began implementing plans for integrated ground and flight testing necessary to achieve the first human launch of Ares I. The individual Ares I flight hardware elements: the first stage five segment booster (FSB), upper stage, and J-2X upper stage engine, will undergo extensive development, qualification, and certification testing prior to flight. Key integrated system tests include the Main Propulsion Test Article (MPTA), acceptance tests of the integrated upper stage and upper stage engine assembly, a full-scale integrated vehicle dynamic test (IVDT), aerodynamic testing to characterize vehicle performance, and integrated testing of the avionics and software components. The Ares I-X development flight test will provide flight data to validate engineering models for aerodynamic performance, stage separation, structural dynamic performance, and control system functionality. The Ares I-Y flight test will validate ascent performance of the first stage, stage separation functionality, and a high- altitude actuation of the launch abort system (LAS) following separation. The Orion-1 flight test will be conducted as a full, un-crewed, operational flight test through the entire ascent flight profile prior to the first crewed launch. Show less

a proposed system for mounting loaded pallets in the cargo bay of a next-generation space-shuttle- like spacecraft, such that the center of mass of the cargo would lie within a 1-in. (2.54-cm) cube that would also contain the center of mass of the spacecraft. The system would include (1) an algorithm for planning the locations of the pallets, given the geometric and weight proper- ties of the pallets, and the geometric re- strictions of the cargo bay; (2) quick- connect/quick-disconnect… Show more

a proposed system for mounting loaded pallets in the cargo bay of a next-generation space-shuttle- like spacecraft, such that the center of mass of the cargo would lie within a 1-in. (2.54-cm) cube that would also contain the center of mass of the spacecraft. The system would include (1) an algorithm for planning the locations of the pallets, given the geometric and weight proper- ties of the pallets, and the geometric re- strictions of the cargo bay; (2) quick- connect/quick-disconnect mounting mechanisms similar to those now used on air hoses; (3) other mounting mech- anisms, comprising mostly spring-loaded pins, in a locking subsystem that would prevent shifting of the pallets under load; and (4) mechanisms for perform- ing fine position adjustments to satisfy the center-of-mass requirement. Show less

Spacecraft are typically designed with a primary focus on weight in order to meet launch vehicle performance parameters. However, for pressurized and/or man-rated spacecraft, it is also necessary to have an understanding of the vehicle operating environments to properly size the pressure vessel. Proper sizing of the pressure vessel requires an understanding of the space vehicle's life cycle and compares the physical design optimization (weight and launch "cost") to downstream operational… Show more

Spacecraft are typically designed with a primary focus on weight in order to meet launch vehicle performance parameters. However, for pressurized and/or man-rated spacecraft, it is also necessary to have an understanding of the vehicle operating environments to properly size the pressure vessel. Proper sizing of the pressure vessel requires an understanding of the space vehicle's life cycle and compares the physical design optimization (weight and launch "cost") to downstream operational complexity and total life cycle cost. This paper will provide an overview of some major environmental design drivers and provide examples for calculating the optimal design pressure versus a selected set of design parameters related to thermal and environmental perspectives. Show less

The proposed paper will focus on the Project Management and Systems Engineering approach utilized to develop a set of both integrated and cohesive requirements for the Exploration Launch Office, within the Constellation Program. A summary of the programmatic drivers which influenced the approach along with details of the resulting implementation will be discussed as well as metrics evaluating the efficiency and accuracy of the various requirements development activities. Requirements… Show more

The proposed paper will focus on the Project Management and Systems Engineering approach utilized to develop a set of both integrated and cohesive requirements for the Exploration Launch Office, within the Constellation Program. A summary of the programmatic drivers which influenced the approach along with details of the resulting implementation will be discussed as well as metrics evaluating the efficiency and accuracy of the various requirements development activities. Requirements development activities will focus on the procedures utilized to ensure that technical content was valid and mature in preparation for the Crew Launch Vehicle and Constellation System s Requirements Reviews. This discussion will begin at initial requirements development during the Exploration Systems Architecture Study and progress through formal development of the program structure. Show less

A newly developed solid-state temperature controller will offer greater flexibility in the thermal control of aerospace vehicle structures. A status of the hardware development along with its implementation on the Multi- Purpose Logistics Module will be provided. Numerous advantages of the device will also be discussed with regards to current and future flight vehicle implementations.

The Multi-Purpose Logistics Module is the primary carrier for transport of pressurized payload to the International Space Station. Performing five missions within a thirteen month span provided a unique opportunity to gather a great deal of information toward understanding and verifying the orbital performance of the vehicle. This paper will provide a brief overview of the hardware history and design capabilities followed by a summary of the missions flown, resource requirements and… Show more

The Multi-Purpose Logistics Module is the primary carrier for transport of pressurized payload to the International Space Station. Performing five missions within a thirteen month span provided a unique opportunity to gather a great deal of information toward understanding and verifying the orbital performance of the vehicle. This paper will provide a brief overview of the hardware history and design capabilities followed by a summary of the missions flown, resource requirements and possibilities for the future. Show less

Aerospace applications with requirements for large capacity heat removal (launch vehicles, platforms, payloads, etc.) typically utilize a liquid coolant fluid as a transport media to increase efficiency and flexibility in the vehicle design. An issue with these systems however, is susceptibility to the presence of noncondensable gas (NCG) or air. The presence of air in a coolant loop can have numerous negative consequences, including loss of centrifugal pump prime, interference with sensor… Show more

Aerospace applications with requirements for large capacity heat removal (launch vehicles, platforms, payloads, etc.) typically utilize a liquid coolant fluid as a transport media to increase efficiency and flexibility in the vehicle design. An issue with these systems however, is susceptibility to the presence of noncondensable gas (NCG) or air. The presence of air in a coolant loop can have numerous negative consequences, including loss of centrifugal pump prime, interference with sensor readings, inhibition of heat transfer, and coolant blockage to remote systems. Hardware ground processing to remove this air is also cumbersome and time consuming which continuously drives recurring costs. Current systems for maintaining the system free of air are tailored and have demonstrated only moderate success. An obvious solution to these problems is the development and advancement of a passive gas removal device, or gas trap, that would be installed in the flight cooling system simplifying the initial coolant fill procedure and also maintaining the system during operations. The proposed device would utilize commercially available membranes thus increasing reliability and reducing cost while also addressing both current and anticipated applications. In addition, it maintains current pressure drop, water loss, and size restrictions while increasing tolerance for pressure increases due to gas build-up in the trap. Show less

The efficiency of re-useable aerospace systems requires a focus on the total operations process rather than just orbital performance. For the Multi-Purpose Logistics Module this activity included special attention to terrestrial conditions both pre-launch and post-landing and how they inter-relate to the mission profile. Several of the efficiencies implemented for the MPLM Mission Engineering were NASA firsts and all served to improve the overall operations activities. This paper will provide… Show more

The efficiency of re-useable aerospace systems requires a focus on the total operations process rather than just orbital performance. For the Multi-Purpose Logistics Module this activity included special attention to terrestrial conditions both pre-launch and post-landing and how they inter-relate to the mission profile. Several of the efficiencies implemented for the MPLM Mission Engineering were NASA firsts and all served to improve the overall operations activities. This paper will provide an explanation of how various issues were addressed and the resulting solutions. Topics range from statistical analysis of over 30 years of atmospheric data at the launch and landing site to a new approach for operations with the Shuttle Carrier Aircraft. In each situation the goal was to "tune" the thermal management of the overall flight system for minimizing requirement risk while optimizing power and energy performance. Show less

The requirement for logistics re-supply of the International Space Station has provided a unique opportunity for engineering the implementation of NASA's first dedicated pressurized logistics carrier fleet. The NASA fleet is comprised of three Multi-Purpose Logistics Modules (MPLM) provided to NASA by the Italian Space Agency. ... Mission engineering of the MPLM program requires a broad focus on three distinct yet inter-related operations processes: pre-flight, flight operations, and… Show more

The requirement for logistics re-supply of the International Space Station has provided a unique opportunity for engineering the implementation of NASA's first dedicated pressurized logistics carrier fleet. The NASA fleet is comprised of three Multi-Purpose Logistics Modules (MPLM) provided to NASA by the Italian Space Agency. ... Mission engineering of the MPLM program requires a broad focus on three distinct yet inter-related operations processes: pre-flight, flight operations, and post-flight turn-around. Within each primary area exist several complex subsets of distinct and inter-related activities. Pre-flight processing includes the evaluation of carrier hardware readiness for space flight. This includes integration of payload into the carrier, integration of the carrier into the launch vehicle, and integration of the carrier onto the orbital platform. Flight operations include the actual carrier operations during flight and any required real-time ground support. Post-flight processing includes de-integration of the carrier hardware from the launch vehicle, de-integration of the payload, and preparation for returning the carrier to pre-flight staging. Typical space operations are engineered around the requirements and objectives of a dedicated mission on a dedicated operational platform (i.e. Launch or Orbiting Vehicle). The MPLM, however, has expanded this envelope by requiring operations with both vehicles during flight as well as pre-launch and post-landing operations. ... Discussion of the process flows and target areas for process improvement are provided in the subject paper. Special emphasis is also placed on supplying guidelines for hardware development. The combination of process knowledge and hardware development knowledge will provide a comprehensive overview for future vehicle developments as related to integration and transportation of payloads. Show less

Part 1. A test was conducted to determine the venting characteristics of multiple-layer insulation (MLI). It involved forcing air through four samples of MLI components and measuring the pressure differences and flow rates. Results from this test have been used to create a mathematical model of the flow through the MLI components. This model is used in a companion paper to predict the results of a second test and the venting behavior of MLI on the Space Station.

Part II. A test was… Show more

Part 1. A test was conducted to determine the venting characteristics of multiple-layer insulation (MLI). It involved forcing air through four samples of MLI components and measuring the pressure differences and flow rates. Results from this test have been used to create a mathematical model of the flow through the MLI components. This model is used in a companion paper to predict the results of a second test and the venting behavior of MLI on the Space Station.

Part II. A test was conducted to determine the venting characteristics of the multiple-layer insulation (MLI) to be installed on the Space Station Freedom (SSF). A full MLI blanket with inter-blanket joints was installed onto a model of a section of the SSF pressure wall, support structure, and debris shield. Data were taken from this test and were used to predict the venting of the actual Space Station pressure-wall/MLI/debris-shield assemply during launch and possible re-entry. It was found that the pressure differences across the debris shields and MLI blankets were well within the specified limits in all cases. Show less