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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 631 records · Page 35
All sourcesNASA NTRSDOE OSTI
NASA NTRS2011

Study of the Dependence on Magnetic Field and Bias Voltage of an AC-Biased TES Microcalorimeter

At SRON we are studying the performance of a Goddard Space Flight Center single pixel TES microcalorimeter operated in the AC bias configuration. For x-ray photons at 6keV the AC biased pixel shows a best energy resolution of 3.7eV, which is about a factor of 2 worse than the energy resolution observed in identical DC-biased pixels. To better understand the reasons of this discrepancy, we investigated the detector performance as a function of temperature, bias working point and applied magnetic field. A strong periodic dependence of the detector noise on the TES AC bias voltage is measured. We discuss the results in the framework of the recent weak-link behaviour observed inTES microcalorimeters.

Bandler, Simon↗
NASA NTRS2012

Entry, Descent, and Landing for Human Mars Missions

One of the most challenging aspects of a human mission to Mars is landing safely on the Martian surface. Mars has such low atmospheric density that decelerating large masses (tens of metric tons) requires methods that have not yet been demonstrated, and are not yet planned in future Mars missions. To identify the most promising options for Mars entry, descent, and landing, and to plan development of the needed technologies, NASA's Human Architecture Team (HAT) has refined candidate methods for emplacing needed elements of the human Mars exploration architecture (such as ascent vehicles and habitats) on the Mars surface. This paper explains the detailed, optimized simulations that have been developed to define the mass needed at Mars arrival to accomplish the entry, descent, and landing functions. Based on previous work, technology options for hypersonic deceleration include rigid, mid-L/D (lift-to-drag ratio) aeroshells, and inflatable aerodynamic decelerators (IADs). The hypersonic IADs, or HIADs, are about 20% less massive than the rigid vehicles, but both have their technology development challenges. For the supersonic regime, supersonic retropropulsion (SRP) is an attractive option, since a propulsive stage must be carried for terminal descent and can be ignited at higher speeds. The use of SRP eliminates the need for an additional deceleration system, but SRP is at a low Technology Readiness Level (TRL) in that the interacting plumes are not well-characterized, and their effect on vehicle stability has not been studied, to date. These architecture-level assessments have been used to define the key performance parameters and a technology development strategy for achieving the challenging mission of landing large payloads on Mars.

Munk, Michelle M.↗
NASA NTRS2012

Study of the Dependency on Magnetic Field and Bias Voltage of an AC-Biased TES Microcalorimeter

At SRON we are studying the performance of a Goddard Space Flight Center single pixel TES microcalorimeter operated in an AC bias configuration. For x-ray photons at 6 keV the pixel shows an x-ray energy resolution Delta E(sub FWHM) = 3.7 eV, which is about a factor 2 worse than the energy resolution observed in an identical DC-biased pixel. In order to better understand the reasons for this discrepancy we characterized the detector as a function of temperature, bias working point and applied perpendicular magnetic field. A strong periodic dependency of the detector noise on the TES AC bias voltage is measured. We discuss the results in the framework of the recently observed weak-link behaviour of a TES microcalorimeter.

Gottardi, L.↗
NASA NTRS2013

The Importance of Earth as a Meteor Detector

In order to understand the complex meteoroid environment that threatens spacecraft in near Earth space, ground based observational techniques provide us with an effective option for evaluating the important parameters of flux, speed, mass, density and directionality. While no observational method (in ]situ or ground based detectors) provides bias free measurements of direct quantities, there are several benefits to using the Earth as a detector for calibrating meteoroid models that extend to the inner Solar System and beyond Earth fs orbit. The Earth constantly interacts with meteoritic particles from comets and asteroids as they evolve from their parent objects through dynamical processes. Modeling these dynamical processes with a physics ]based approach can help reveal the causes of observational features but developing those models involves constraining sequences of poorly defined parameters. These parameters must be tuned to a particular detector that offers direct or indirect measurements of mass, density, flux and speed - the quantities used in evaluating penetration risk. The following topics will be discussed: a) Consistency between ground based and in.situ measurements of flux in Earth orbit. b) Consistency between radar and electro.optical speed determinations and agreement of these with dynamical studies. c) The fact that there are six sporadic sources which cannot be determined by integrated line of sight emissivity: Observations using IRAS or COBE cannot give you all important directionality needed for risk evaluations. d) The large collecting area of the Earth s atmosphere compared to in.situ detectors gives better number statistics in the threat regime. The NASA Meteoroid Environment Office utilizes ground based radar and electro.optical measurements to calibrate the Meteoroid Engineering Model (MEM). As MEM is an engineering design model our main emphasis is on threat size particle, speed, flux and directionality. However, MEM has acknowledged limitations particularly with regard to source strength as a function of mass and work is proceeding with improved distributions that will rectify many of these shortcomings.

Koehler, Heather↗
NASA NTRS2013

Composite Design and Manufacturing Development for Human Spacecrafts

The Structural Engineering Division at the NASA Johnson Space Center (JSC) has begun work on lightweight, multi‐functional pressurized composite structures. The first candidate vehicle for technology development is the Multi‐Mission Space Exploration Vehicle (MMSEV) cabin, known as the Gen 2B cabin, which has been built at JSC by the Robotics Division. Of the habitable MMSEV vehicle prototypes designed to date, this is the first one specifically analyzed and tested to hold internal pressure and the only one made out of composite materials. This design uses a laminate base with zoned reinforcement and external stringers, intended to demonstrate certain capabilities, and to prepare for the next cabin design, which will be a composite sandwich panel construction with multi‐functional capabilities. As part of this advanced development process, a number of new technologies were used to assist in the design and manufacturing process. One of the methods, new to JSC, was to build the Gen 2B cabin with Out of Autoclave technology to permit the creation of larger parts with fewer joints. An 8‐ply pre‐preg layup was constructed to form the cabin body. Prior to lay‐up, a design optimization software called FiberSIM was used to create each ply pattern. This software is integrated with Pro/Engineer to allow for customized draping of each fabric ply over the complex tool surface. Slits and darts are made in the software model to create an optimal design that maintains proper fiber placement and orientation. The flat pattern of each ply is then exported and sent to an automated cutting table where the patterns are cut out of graphite material. Additionally, to assist in lay‐up, a laser projection system (LPT) is used to project outlines of each ply directly onto the tool face for accurate fiber placement and ply build‐up. Finally, as part of the OoA process, a large oven was procured to post‐cure each part. After manufacturing complete, the cabin underwent modal and pressure testing (currently in progress at date of writing) and will go on to be outfitted and used for further ops usage.

Litteken, Douglas↗
NASA NTRS2011

Laboratory Testing of a Phased Induced Amplitude Apodization (PIAA) Coronagraph

We present high-contrast images from laboratory testing of a Phase Induced Amplitude Apodization (PIAA) coronagraph at NASA's High Contrast Imaging Testbed (HCIT). Using a deformable mirror and wavefront estimation and control algorithms, we create a 'dark hole' in the monochromatic point-spread function with an inner working angle of (2.05 f lambda/D), with a mean intensity 3.5x10(exp -8). We discuss the contributions to this floor, and the techniques being developed to improve it. We also present simulations that investigate the effect of Lyot stops of various sizes, and conclude that a Lyot stop is necessary for 10(exp -9) performance but that an annular postapodizer is not necessary.

deformable mirror↗
NASA NTRS2016

BRDF Characterization and Calibration Inter-Comparison between Terra MODIS, Aqua MODIS, and S-NPP VIIRS

The inter-comparison of reflective solar bands (RSB) between Terra MODIS, Aqua MODIS, and SNPP VIIRS is very important for assessment of each instrument's calibration and to identify calibration improvements. One of the limitations of using their ground observations for the assessment is a lack of the simultaneous nadir overpasses (SNOs) over selected pseudo-invariant targets. In addition, their measurements over a selected Earth view target have significant difference in solar and view angles, and these differences magnify the effects of Bidirectional Reflectance Distribution Function (BRDF). In this work, an inter-comparison technique using a semi-empirical BRDF model is developed for reflectance correction. BRDF characterization requires a broad coverage of solar and view angles in the measurements over selected pseudo-invariant targets. Reflectance measurements over Libya 1, 2, and 4 desert sites from both the Aqua and Terra MODIS are regressed to a BRDF model with an adjustable coefficient accounting for the calibration difference between the two instruments. The BRDF coefficients for three desert sites for MODIS bands 1 to 9 are derived and the wavelength dependencies are presented. The analysis and inter-comparison are for MODIS bands 1 to 9 and VIIRS moderate resolution radiometric bands (M bands) M1, M2, M4, M5, M7, M8, M10 and imaging bands (I bands) I1-I3. Results show that the ratios from different sites are in good agreement. The ratios between Terra and Aqua MODIS from year 2003 to 2014 are presented. The inter-comparison between MODIS and VIIRS are analyzed for year 2014.

Chang, Tiejun↗
NASA NTRS2018

Agency Agreements Process Champion Support Intern

This document will provide information on the 2018 Spring semester NIFS Intern who represented the Office of Chief Financial Officer (OCFO) as a Reimbursable Accountant at Kennedy Space Center (KSC). This intern supported the Agency Agreements Process Champions and Team Lead, Susan Kroskey, Sandy Massey and Mecca Murphy, with major initiatives to advance the KSC OCFO's vision of creating and innovating healthy financial management practices that maximize the value of resources entrusted to NASA. These initiatives include, but are not limited to: updating the Agency Guidance and NASA Procedural Guidance 9090.1 Agreements, implementing a new budget structure to be utilized across all centers, submitting a Call Request (CRQ) to enhance non-federal customer reporting, initiating a discussion to incorporate a 3-year funding program for NASA agreements, and undertaking the Office of Inspector General (OIG) Audit. In support of these initiatives, this intern identified technical methods to enhance and reduce the workload of financial processes for reimbursable and non-reimbursable agreements, prepared reports in support of accounting functions, and performed administrative work and miscellaneous technical tasks in support of the OCFO as requested. In conclusion of the internship, the intern will become knowledgeable on reimbursable accounting, reimbursable policy, types of reimbursable agreements, the agreements process, estimated pricing reports, and the roles and responsibilities of the Financial Accounting and Financial Services offices.

Process Champion↗
NASA NTRS2019

NASA GIBS and Worldview: Bringing 20 Years of Terra Data into View

For nearly 10 years, the NASA Global Imagery Browse Services (GIBS) and Worldview interactive mapping site have provided users full resolution visualizations of Terra land, cryosphere, ocean, and atmosphere science parameters available within hours of acquisition. Over that time, GIBS and Worldview have expanded their Terra visualization suite to include even more parameters covering the entire mission of science data. Users can now view daily visualizations of nearly 50 near-real time and over 125 science quality science parameters from Terra instruments. These visualizations provide a unique capability for a broad user base to interact and discover the wealth of information sense by instruments on the Terra platform. By viewing Terra-based visualizations in a single location, users can correlate retrievals across instruments. Additionally, GIBS and Worldview include visualizations from many other platforms, allowing for an even greater data discovery capability.The GIBS and Worldview teams continue to work with Terra instrument science teams to add more visualized layers, as well as supporting visualization updates as the data is continually improved. Additionally, the GIBS interfaces and Worldview site are actively working on improved visualization functionality, including vector- and granule/swath-based products, to better address the expanding needs of its user community. This presentation will focus on an overview of existing and future visualization products and capabilities that have supported, and will support, a broad use of Terra data in science, media, and application communities.

Cechini, Matthew↗
NASA NTRSDate not supplied

Guidance for Designing Safety into Urban Air Mobility: Hazard Analysis Techniques

The national airspace system is exceptionally safe, specifically in terms of commercial air traffic operations. The introduction of innovative aircraft (such as electric vertical takeoff and landing vehicles) undergoing novel operations (such as for an urban air passenger carrying mission) is a potential disruptor to the current means of regulating and ensuring the safety of air travel. The aviation industry and associated regulatory bodies are adapting their approaches to assuring system safety to enable these new paradigms. However, any system safety analysis requires that a hazard assessment be performed. In this work, we consider the Functional Hazard Assessment (FHA) and Systems Theoretic Process Analysis (STPA) techniques for hazard assessment and evaluate whether they can be used in a complementary fashion for regulatory approval purposes. We perform an FHA and an STPA on an electric vertical takeoff and landing (eVTOL) vehicle undergoing an urban air mobility (UAM) passenger carrying reference scenario and present excerpts of this analysis. We then draw parallels between the techniques and highlight elements where they naturally reinforce to each other’s results, specifically in the consideration of hazard severity with respect to flight phases, the design of hazard mitigations, and the applicability of the results to all types of regulatory approvals (e.g., type certification, operational approval, and crew training).

Mallory S Graydon↗
NASA NTRS2020

Design Variants of a Common Habitat for Moon and Mars Exploration

The Common Habitat is a long-duration habitat concept based on the Skylab II architecture that leverages a single, multi-destination design applicable to microgravity Mars transit, 1/6 g lunar surface, 3/8 g Mars surface, and 1 g Earth. A trade study for the Common Habitat will address vertical versus horizontal internal orientation and a crew size of four or eight crew. This has resulted in the creation of four variants of the Common Habitat: Four Crew Horizontal Configuration, Four Crew Vertical Configuration, Eight Crew Horizontal Configuration, and Eight Crew Vertical Configuration. Design guidelines that shaped the four configurations are discussed, including: mission duration, destinations/missions, pressure vessel, hatches and docking, subsystems and utilities, lander integration and offloading, and eight-crew extensibility. Functional capabilities for crew-related systems are also discussed, including: private habitation, meal preparation, meal consumption, medical operations, exercise, group socialization and recreation, human waste collection, hygiene, logistics, spacecraft monitoring and commanding, mission planning, robotics and teleoperation, scientific research, maintenance and fabrication, and EVA. Each of the four Common Habitat designs will be presented, with a deck-by-deck description of each workstation, crew station, or subsystem along with an assessment of its degree of compliance with the guidelines and functional capabilities. Finally, forward work will be identified that will down-select a single Common Habitat. This includes multiple analyses that will be performed on the four variants, a down-selection process, and design refinement goals for the selected variant.

Habitability↗
NASA NTRS2018

Development of Low-Scatter Optical Edges for Starshades

Starshades, combined with future space telescopes, provide the ability to detect Earth-like exoplanets in the habitable zone by producing high contrast ratios at small inner working angles. The primary function of a starshade is to suppress light from a target star such that its orbiting planets are revealed. In order to do so, the optical edges of the starshade must maintain their precise in-plane profile to produce the necessary apodization function. However, an equally important consideration is the interaction of these edges with light emanating from our own Sun as scattered and/or diffracted sunlight can significantly degrade the achievable contrast. This paper describes the technical efforts performed to obtain precision, low-scatter optical edges for future starshades. Trades between edge radius (i.e. sharpness) and surface reflectivity have been made and small-scale coupons have been produced using scalable manufacturing processes. A custom scattered light testbed has been developed to quantify the magnitude of scattered light over all sun angles. Models have also been developed to make predictions on the level of reflected and/or diffracted light for various edge architectures. The results of these studies have established a current baseline approach which implements photochemical etching techniques on thin metal foils.

Bradley, Christine↗
NASA NTRSDate not supplied

Functional Task Tests in Partial Gravity During Parabolic Flight

BACKGROUND Critical mission tasks that are required by crews immediately after landing on a planetary surface are seat egress, jump, and walk. To be able to define an effective and comprehensive countermeasure strategy for preserving crew performance during exploration-class missions, there is a need to understand how these functional tasks are actually performed in partial gravity such as on the Moon or Mars. We propose to study the performance in the execution of these tasks during the partial gravity and hypergravity phases of parabolic flight. These tasks will be completed using the same equipment and procedures as the Standard Measures Sensorimotor protocol, which is performed by astronauts returning from spaceflight and by ground-based subjects after prolonged axial body unloading during bed rest. HYPOTHESIS We hypothesize that partial gravity during parabolic flight will cause acute changes in vestibular, proprioceptive, and sensorimotor functions, and these changes will impact the performance of mission critical tasks such as standing, walking, and jumping. The largest changes in performance are expected at the lowest gravity level (0.25g) because subjects will no longer be able to use the gravitational reference for the perception of vertical. Ultimately, this information could be used to assess performance risks and inform the design of countermeasures for NASA exploration-class human missions. METHODS Twelve subjects will be tested during three flights of 30 parabolas, including 10 parabolas at 0.25g, 10 parabolas at 0.5g and 10 parabolas at 0.75g. Subject also will perform tests in 1g between parabolas and in hypergravity (1.8g) during the pull-out phases. Subjects will perform the same tasks as those tested on astronauts returning from spaceflight: sit-to-stand and obstacle walk, tandem walk, jump down, and recovery from fall. Measurements will include: (a) the time for the subject to complete the test (sit-to-stand and obstacle walk, recovery from fall); (b) the time elapsed between the start of motion and the stabilization of upright posture (recovery from fall, jump down); (c) the mean sway speed during quiet standing (recovery from fall, jump down); (d) changes in heart rate and blood pressure (recovery from fall); (e) the percentage of correct steps and torso acceleration (tandem walk); and (f) the severity of motion sickness symptoms. RELEVANCE Although gravitational dose-response curves have been obtained for some biochemical systems in animals, these dose-responses are unknown for most human physiologic systems. Our study will compare the outcomes of 5 functional task tests in 0.25g, 0.5g, 0.75g, 1g, and 1.8g with those previously obtained in ground-based subjects after prolonged axial body unloading and in astronauts immediately after spaceflight. This comparison will help understanding the true extent of functional task performance deficits in partial gravity. The dose-response relationship between gravity level and task performance decrement also will help determining the gravity threshold for these functional tasks. ACKNOWLEDGEMENT This work is supported by the NASA’s Human Research Program Human Health Countermeasures Element

Gilles Clement↗
NASA NTRSDate not supplied

RTG Radiator Efficiency in the Presence of Lunar Dust

The accumulation of Lunar dust on various surfaces is the subject of much recent study, yet is still poorly understood. Recent plans to return humans to the Moon as part of the Artemis program mean that the presence of robust infrastructure to support a permanent human presence is inevitable. Power supply systems, such as Radioisotope Thermoelectric Generators are a likely part of that infrastructure, but require radiative thermal dissipation through a series of radiator fins to function effectively. In this work, the results of a parametric study of the impact on radiator efficiency due to various quantities and types of lunar dust simulants are presented, determining that the impact from low levels of lunar dust accumulation is not significantly detrimental to the efficiency of Multi-Mission Radioisotope Thermoelectric Generator performance in a vacuum, but increased fidelity of data would improve these findings.

Dust↗
NASA NTRSDate not supplied

Functional Task Tests in Partial Gravity During Parabolic Flight

BACKGROUND Critical mission tasks required by crews immediately after landing on a planetary surface include walking, jumping, and egressing from a seat. Understanding how these functional tasks are performed in partial gravity such as on the moon or Mars is necessary to define effective and comprehensive countermeasure strategies for preserving crew performance during exploration-class missions. We propose to study the performance of these tasks during the partial gravity phases of parabolic flight. These tasks will be performed using the same equipment and procedures as those used with astronauts returning from spaceflight and with ground-based subjects after prolonged axial body unloading during bed rest (sensorimotor standard measures). HYPOTHESIS We hypothesize that partial gravity during parabolic flight will cause acute changes in vestibular, proprioceptive, and sensorimotor functions, and these changes will impact the performance of mission critical tasks such as standing, walking, and jumping. The largest changes in performance are expected at the lowest gravity level (0.25g) because subjects will no longer be able to use the gravitational reference for the perception of upright. Ultimately, this information could be used to assess performance risks and inform the design of countermeasures for NASA exploration-class human missions. METHODS Twelve subjects will be tested during three flights of 30 parabolas, including 10 parabolas at 0.25g, 10 parabolas at 0.5g, and 10 parabolas at 0.75g. Subjects also will perform tests in 1g between parabolas. The tasks will be the same as those tested on astronauts returning from spaceflight: sit-to-stand with obstacle walk, tandem rail balance, jump down, and recovery from fall. Measurements will include: (a) time to test completion (sit-to-stand with obstacle walk, recovery from fall); (b) time elapsed between the start of motion and the stabilization of upright posture (recovery from fall, jump down); (c) mean sway speed during quiet standing (recovery from fall, jump down); (d) changes in heart rate and blood pressure (recovery from fall); (e) balance time and torso accelerations (tandem rail balance); (f) cone of stability (jump down); and (g) severity of motion sickness symptoms. RELEVANCE Although gravitational dose-response curves have been obtained for some biochemical systems in animals, these dose-responses are unknown for most human physiologic systems. Our study will compare the outcomes of four functional task tests in 0.25g, 0.5g, 0.75g, and 1g with those previously obtained in ground-based subjects after prolonged axial body unloading and in astronauts immediately after spaceflight. These comparisons will help us understand the true extent of functional task performance deficits in partial gravity. The dose-response relationship between gravity level and task performance decrement also will help determining the gravity threshold for these functional tasks. ACKNOWLEDGEMENT This work is supported by the NASA’s Human Research Program Human Health Countermeasures Element.

T. R. Macaulay↗
DOE OSTI2025

LDRD conclusion poster - Synthesizing Heterometallic Uranium Single Crystals to Understand the Influence of the Secondary Metals on Uranyl Axial Bond Strength

Understanding how transition metals influenced the chemistry of lanthanide and actinide (f-element) materials is critical for advancing separation technologies, materials design, and coordination chemistry. This project examined how incorporating first-row transition metals affected the structural and spectroscopic properties of f-element coordination polymers. In uranium(VI)-based systems synthesized with 2,6-pyridinedicarboxylic acid (PDC) ligands, single-crystal X-ray diffraction and Raman spectroscopy revealed that the presence of transition metals shortened the uranyl axial bond and induced a blue shift in its symmetric stretching vibration—evidence of increased bond strength. Electronic structure analysis, including Density of States (DOS) calculations using density functional theory (DFT), revealed altered orbital overlaps and highlighted the role of transition metal d-orbitals in modulating bonding. Raman modes were modeled using truncated structural fragments in collaboration with the University of Notre Dame, and although the predicted frequencies were lower than experimental values, they remained within expected ranges. In parallel, similar experiments with cerium (Ce) in the presence of cobalt (Co) and PDC demonstrated multi-step single-crystal-to-single-crystal transformations—behavior not observed in the uranium systems. Initial products included light yellow, orange, and polycrystalline materials. Single-crystal X-ray diffraction studies, conducted in collaboration with the Colorado School of Mines, identified the yellow phase as monometallic Ce(PDC)2(H2O)2·4H2O and the orange phase as heterometallic Ce2Co(PDC)4(H2O)6. After standing in solution for one week, both phases fully transformed into a dark yellow crystalline phase, [Ce3(PDC)5(H2O)8].6(H2O). Remarkably, this transformation was reversible—disturbing the equilibrium by removing some crystals caused reversion to the initial Ce(PDC)2(H2O)2·4H2O phase, highlighting dynamic behavior. All three structures were previously unreported. Solid-state UV-visible and Raman spectroscopy further distinguished these phases, revealing ligand-to-metal charge transfer involving Ce and characteristic d–d transitions from Co(II). The precise mechanism driving these transformations remained unclear; however, pH-dependent experiments confirmed that the transformation did not occur when the pH decreased. Overall, the project demonstrated that transition metals could be employed to tune bonding interactions, structural dimensionality, and optical properties in f-element materials, establishing new pathways for designing functional heterometallic systems. The work resulted in several novel structural discoveries and fostered productive collaborations with the University of Notre Dame and the Colorado School of Mines.

37 - INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL C↗
NASA NTRS1996

[Formian 2 and a Formian Function for Processing Polyhedric Configurations]

The work began in October 1994 with the following objectives: (1) to produce an improved version of the programming language Formian; and (2) to create a means for computer aided handling of polyhedric configurations including the geodesic forms of all kinds. A new version of Formian, referred to as Formian 2, is being implemented to operate in the Windows 95 environment. It is an ideal tool for configuration management in a convenient and user-friendly manner. The second objective was achieved by creating a standard Formian function that allows convenient handling of all types of polyhedric configurations. In particular, the focus of attention is on polyhedric configurations that are of importance in architectural and structural engineering fields. The natural medium for processing of polyhedric configurations is a programming language that incorporates the concepts of 'formex algebra'. Formian is such a programming language in which the processing of polyhedric configurations can be carried out using the standard elements of the language. A description of this function is included in a chapter for a book entitled 'Beyond the Cube: the Architecture of space Frames and Polyhedra'. A copy of this chapter is appended.

Nooshin, H.↗
NASA NTRS2014

Reflections on Centaur Upper Stage Integration by the NASA Lewis (Glenn) Research Center

The NASA Glenn (then Lewis) Research Center (GRC) led several expendable launch vehicle (ELV) projects from 1963 to 1998, most notably the Centaur upper stage. These major, comprehensive projects included system management, system development, integration (both payload and stage), and launch operations. The integration role that GRC pioneered was truly unique and highly successful. Its philosophy, scope, and content were not just invaluable to the missions and vehicles it supported, but also had significant Agencywide benefits. An overview of the NASA Lewis Research Center (now the NASA Glenn Research Center) philosophy on ELV integration is provided, focusing on Atlas/Centaur, Titan/Centaur, and Shuttle/Centaur vehicles and programs. The necessity of having a stable, highly technically competent in-house staff is discussed. Significant depth of technical penetration of contractor work is another critical component. Functioning as a cohesive team was more than a concept: GRC senior management, NASA Headquarters, contractors, payload users, and all staff worked together. The scope, content, and history of launch vehicle integration at GRC are broadly discussed. Payload integration is compared to stage development integration in terms of engineering and organization. Finally, the transition from buying launch vehicles to buying launch services is discussed, and thoughts on future possibilities of employing the successful GRC experience in integrating ELV systems like Centaur are explored.

Launch Vehicle↗