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Several novel active and passive means for the suppression of pilot-induced oscillations are considered in the paper. The potential of the proposed means in eliminating Category I, II, and III pilot-induced oscillations was studied in ground-based simulation for two controlled element dynamics corresponding to an aerospace vehicle and a second-generation supersonic transport. The experiments demonstrated that the highest effectiveness in suppressing pilot-induced oscillations and improving task performance is provided by integrating both proposed active suppressors with one of the passive prefilters. • Novel nonlinear prefilters eliminate Category 1, 2, and 3 PIO events. • Proposed novel active suppressors are effective means for PIO elimination. • Integration of prefilters and active suppressors provides the best task performance. [ABSTRACT FROM AUTHOR]

A new renewable energy-driven advanced plant is designed and developed to produce multiple useful outputs, namely electricity, heat, cooling, hydrogen, and monomethylhydrazine (as space shuttle fuel) using solar and wind energies locally available. A specific location needed for this kind of unique work is identified as the Kennedy Space Center (KSC), which is known as located on Merritt Island, in the state of Florida (USA). It is also one of the National Aeronautics and Space Administration's (NASA) ten field centers. Since December 1968, KSC has been NASA's primary launch center of American spaceflight, research, and technology. This paper presents a comprehensive analysis of the subsystems that constitute the newly proposed system potentially for KSC and highlights their complex relationships and synergies. Leveraging renewable energy sources, such as concentrated solar power (CSP) and wind energy, coupled with the subsystem uniquely, such as the regenerative Rankine cycle, multi-stage flash (MSF) desalination unit, hydrogen production process, and Li–Br absorption chiller, the KSC's system maximizes energy conversion efficiency while minimizing environmental impact. Noteworthy outcomes include daily water production of 177.63 kg/s and hydrogen production of 169.61 kg/day, alongside annual energy contributions of 212,692,688 kWh for CSP and 66,158,552 kWh for wind turbines. More than that, it produces 23.04 kg/s MMH as fuel. Additionally, the overall energy and exergy efficiencies of the system are 30.6% and 33% respectively. Despite challenges, such as low efficiencies in certain subsystems, like mono methyl hydrazine (MMH) production, ongoing research and development efforts aim to optimize processes and enhance sustainability. [ABSTRACT FROM AUTHOR]

On July 20, 1969, Neil Armstrong and Buzz Aldrin took the first human steps on a celestial body other than Earth. Just over two weeks later, on August 4, NASA presented to a committee charged with making recommendations on the U.S. post-Apollo space program a bold plan of continued lunar and Martian exploration. Over the next six months, that plan was decisively rejected by the administration of President Richard M. Nixon. In 1970, NASA canceled the final two Apollo missions to the Moon, and on January 5, 1972, President Nixon announced approval of the space shuttle program. Focusing the U.S. space program on operating the space shuttle and building a space station has kept the United States human space flight program confined to low Earth orbit for over four decades. There are lessons to be learned from the post-Apollo decisions in the United States for today's attempts to gain political support for a renewed and sustainable program of human exploration of the Moon, Mars, and other solar system destinations. This paper, drawing on in-depth research on the events of the 1969–1972 period in U.S. space policy, will discuss those lessons. [ABSTRACT FROM AUTHOR]

The Shuttle Hypervelocity Impact Database documents damage features on each Orbiter from micrometeoroids (MM) and orbital debris (OD). Data is divided into tables for crew module windows, payload bay door radiators and thermal protection systems along with other miscellaneous regions. The database contains nearly 3000 records, with each providing impact feature dimensions, location on the vehicle and relevant mission information. Additional detail on the type and size of particle that produced the damage site is provided when sampling data and definitive spectroscopic analysis results are available. Relationships assumed when converting from observed feature sizes in different shuttle materials to particle sizes will be presented. [ABSTRACT FROM AUTHOR]

Abstract: Long-term analysis of data from two radiation detection instruments on the International Space Station (ISS) shows that the docking of the Space Shuttle drops down the measured dose rates in the region of the South Atlantic Anomaly (SAA) by a factor of 1.5–3. Measurements either by the R3DE detector, which is outside the ISS at the EuTEF facility on the Columbus module behind a shielding of less than 0.45gcm−2, and by the three detectors of the Liulin-5 particle telescope, which is inside the Russian PEARS module in the spherical tissue equivalent phantom behind much heavier shielding demonstrate that effect. Simultaneously the estimated averaged incident energies of the incoming protons rise up from about 30 to 45MeV. The effect is explained by the additional shielding against the SAA 30–150MeV protons, provided by the 78 tons Shuttle to the instruments inside and outside of the ISS. An additional reason is the ISS attitude change (performed for the Shuttle docking) leading to decreasing of dose rates in two of Liulin-5 detectors because of the East–West proton fluxes asymmetry in SAA. The Galactic Cosmic Rays dose rates are practically not affected. [Copyright &y& Elsevier]

Abstract: Given the diversity of missions it has accomplished and the myriad of adaptations it has undergone, the US Space Shuttle is widely regarded as a highly flexible space vehicle. With the Shuttle’s upcoming 2011 retirement, it is instructive to survey the history of this vehicle’s flexibility for the insights it can provide to the design and characterization of flexibility in future space systems. Data are presented on the evolution of mission requirements over time for 120 missions performed by the Space Shuttle over a period of some 27 years. Distinct trends in the time domain – as well as their causes – are identified and discussed, and early manifest plans from 1982 serve as a confirmation that these trends were not originally anticipated. Eight examples are then presented of engineering modifications that allowed the Shuttle to adapt and accommodate these requirement changes. Several additional instances of Shuttle flexibility are explored, such as post-Columbia disaster modification, upgrade programs and derived vehicles, and one case in which flexibility was inhibited by an early design decision. [ABSTRACT FROM AUTHOR]

Abstract: Char deposits on recovered fragments of space shuttle Columbia windowpanes were analyzed to further understand the events that occurred during orbiter reentry and breakup. The TEM analysis demonstrated that oxides of aluminum and titanium mixed with silicon oxides to preserve a history of thermal conditions to which portions of the vehicle were exposed. The presence of Ti during the beginning of the deposition process, along with the thermodynamic phase precipitation upon cool down, indicated that temperatures well above the Ti melt point were experienced. The stratified observations implied that additional exothermic reactions, expectedly metal combustion of a Ti–6Al–4V structure, had to occur for oxide formation. Results are significant for aerospace vehicles, where thermal protection system (TPS) breaches could cause material originally designed for substructural applications to be in direct path with reentry plasma. [Copyright &y& Elsevier]

Abstract: The loss of the space shuttle Columbia in 2003 was caused by the impact of foam insulation on the leading edge of the wing. The foam strike created a hole in reinforced carbon–carbon panel 8 that led to excessive heating during re-entry, loss of the integrity of the left wing, and subsequent loss of the vehicle and crew. In the 2.5 years following the accident, there was a concerted effort to understand the impact threat to the space shuttle system. The effort was a large one, and was comprised of five integrated parts: (1) identifying the debris that can be shed by the External Tank and Solid Rocket Boosters; (2) determining the impact speeds and angles that debris can strike the Orbiter; (3) quantifying the amount of damage to the thermal protection system caused by those strikes; (4) estimating the temperature rise in the damaged regions during re-entry; and (5) deciding whether the temperature rise is sufficient to affect structural integrity. Each of these parts was addressed through experimentation and the development of what are called within the space shuttle program Critical Math Models. These models are extensively verified and validated to give high confidence in their results and are baselined by the shuttle program. This paper overviews the extensive experimental and modeling efforts of the return-to-flight program, emphasizing the impact testing and modeling. [Copyright &y& Elsevier]

• A simulation-based risk assessment method, inspired by human reasoning, is proposed. • Engineering knowledge about the system is explicitly used to guide the simulation. • An exploration strategy is used to generate risky scenarios in complex systems. • The method is utilized to perform risk assessment of a Space Shuttle ascent phase. Probabilistic risk assessment (PRA) is a systematic process of examining how engineered systems work to ensure safety. With the growth of the size of dynamic systems and the complexity of the interactions between hardware, software, and humans, it is extremely difficult to enumerate risky scenarios by the traditional PRA methods. In this study, a new dynamic probabilistic risk assessment methodology is proposed that employs a new exploration strategy to generate risky scenarios. The proposed methodology consists of three main modules, including simulation, planner, and scheduler. In this methodology, the engineering knowledge of the system is explicitly used to guide the simulation module to achieve higher efficiency and accuracy. The engineering knowledge is reflected in the planner module which is responsible for generating plans as a high-level map to guide the simulation. The scheduler module is responsible for guiding the simulation by controlling the timing and occurrence of the random events. In this paper, modules of the proposed methodology, and their interactions are explained in detail. The developed methodology is used to perform risk assessment of a Space Shuttle ascent phase, and results show the effectiveness of the proposed platform. [ABSTRACT FROM AUTHOR]

Abstract: While the first space station in American culture was described in an 1869 work of fiction in the Atlantic Monthly, in the twentieth century the idea proliferated through all cultures as the sine qua non enabling technology for space exploration. In the latter part of the 1960s many in the leadership of NASA realized that the kind of resources that had been made available for the sprint to the Moon that was Project Apollo would not be repeated. They turned to advocating the development of major projects that would create for the United States a permanent infrastructure in space, and eventually the capability to leave Earth permanently. This involved as its centerpieces the development of an orbital workshop leading to a space station, and a reusable vehicle to transport people and cargo to and from Earth orbit with a modicum of efficiency. This found realization through the building of the International Space Station (ISS) at the end of the century. But even as ISS became a reality, on February 1, 2003, its role was made tenuous by the loss of the Columbia space shuttle and the grounding of the fleet. On January 14, 2004, moreover, President George W. Bush announced a reorientation of NASA''s programs to emphasize a return to the Moon and a human expedition to Mars. In that context, he advocated the retirement of the Space Shuttle by 2010 and the ending of U.S. involvement in ISS before 2020. Suddenly, the space station had become irrelevant to American efforts in space. The history of space stations and their development over time, and what it portends for the future of space policy, is the subject of this essay. [Copyright &y& Elsevier]

Abstract: The brackets that secure the liquid oxygen feed line to the external tank are known locations of frost and ice growth during the pre-launch period following fuel loading. This experimental program quantified the reduction in adhesion that resulted when ice phobic coatings were applied to test coupons that simulated the bracket surface. Double lap shear testing of coated and uncoated coupons provided robust test specimens and consistent load response patterns with exceptional resolution. Ice was grown as strong and consistently as possible for these tests and then subjected to temperature decreases comparable to those of the bracket. All tests were conducted at a constant temperature of −112 °C (−170 °F) and included uncoated controls with each group of samples. The program evolved in three phases. Phase 1 evaluated a wide range of coatings, and showed that Rain-X mixed with MP-55 powdered Teflon (RXM) was an outstanding coating to reduce ice adhesion to Koropon coated aluminum. Coating material retained on the ice surface following each test indicated failure in the coating and the potential for loss of effectiveness with repeated ice formation and release. Phase 2 evaluated modifications to RXM that might enhance durability while maintaining effectiveness. However, the modified mixtures did not improve coating durability or ice release. Phase 3 focused on the effects of mixing method, cure time, wiping off of excess coating, and coating resistance to weathering by water. A progressive coating loss again occurred through repeat test cycles, but performance generally improved. Results also indicated that cure times longer than 1.5 h prior to coating disturbance are needed for optimal performance. The MP-55 remaining on coupon surfaces after 3 cycles of testing and on one untested coupon from the same group was measured with XPS. The tested coupons retained slightly less MP-55 than the untested coupon, confirming the loss of coating. Contact angle analysis of these same coupons showed that the hydrophobic performance of the tested surfaces was largely preserved. Scanning electron microscopy with an energy dispersive spectroscopy elemental map indicated that the MP-55 was evenly dispersed throughout the coated surface, and abrasive wiping did not remove a significant portion of the Teflon. Test results suggest follow-up studies to refine the optimal coating formulation, mixing and application procedures, and understanding of reaction processes, cure time, and coating durability. Double lap shear testing and XPS analysis can quantify ice adhesion and coating profile thickness changes with cycling, and is capable of resolving these remaining issues. [Copyright &y& Elsevier]

Abstract: Visual observations by space shuttle astronauts have described a phenomenon in which spatially distant thunderstorm cells seem to reciprocally “ignite” lightning flashes in a semi-cyclic sequence. Lightning occurring in one cell is immediately followed by lightning in other cells, separated by tens or hundreds of kilometers. We present quantitative analysis of lightning observations conducted within the framework of the MEIDEX-sprite campaign on board the space shuttle Columbia in January 2003 [Yair, Y., Israelevich, P., Devir, A., Moalem, M., Price, C., Joseph, J., Levin, Z., Ziv, B., Teller, A., 2004. New sprites observations from the space shuttle. Journal of Geophysical Research 109, D15201/10.1029/2003JD004497]. Video footage of 6 storm systems with varying flash rates, which occurred over Africa, South America, Australia and the Pacific Ocean were analyzed. It is found that when the storm flash rate was high, lightning activity in horizontally remote electrically active cells became clustered, with bursts of nearly simultaneous activity separated by quiet periods. The recurrence time was ∼2.5s, close to the previously reported time delay between consecutive ELF transient signals in the Schumann resonance range [Füllekrug, M., 1995. Schumann resonances in magnetic filed components. Journal of Atmospheric and Terresterial Physics 57, 479–484]. We propose that this behavior is similar to the collective dynamics of a network of weakly coupled limit-cycle oscillators [Strogatz, S.H., 2000, From Kuramoto to Crawford: exploring the onset of synchronization in populations of coupled oscillators. Physica, D, 1–20]. Thunderstorm cells embedded within a mesoscale convective system (MCS) constitute such a network, and their lightning frequency is best described in terms of phase-locking of a globally coupled array [Kourtchatov, S.Y., Yu, V.V., Likhanskii, V.V., Napartovitch, A.P., Arecchi, F.T., Lapucci, A., 1995 Theory of phase locking of globally coupled laser arrays. Phys. Rev. A 52, 4089–4094]. Comparison of basic parameters of the lightning networks with predictions of random-graph models reveals that the networks cannot be described by the classical random-graph model [Erdos, P., Renyi, A., 1960. On the evolution of random graphs. Publ. Math. Inst. Hung. Acad. Sci., 5, 17–61], but are more compatible with generalized random-graphs with a prescribed degree distribution [Newman, M.E.J., Strogatz, S.H., Watts, D.J., 2001. Random graphs with arbitrary degree distributions and their applications. Phys. Rev. E 64, 026118] that exhibit a high clustering coefficient and small average path lengths. Such networks are capable of supporting fast response, synchronization and coherent oscillations [Lago-Fernandez, L.F., Huerta, R., Corbacho, F., Siguenza, J.A., 2000. Fast response and temporal coherent oscillations in small-world networks. Physical Review Letters 84, 2758–2761]. Several physical mechanisms are suggested to explain the observed phenomenon. [Copyright &y& Elsevier]

Abstract: In the GENEX (GENe EXpression) spaceflight experiment (flown on STS-87), six surface sterilized soybean seeds (Glycine max cv McCall) were inserted into each of 32 autoclaved plastic seed growth pouches containing an inner germination paper sleeve (for a total of 192 seeds). The pouches were stowed within a mid-deck locker until Mission Flight Day 10, at which time an astronaut added water to initiate the process of seed germination on-orbit and subsequently transferred them to four light-tight aluminum canisters called BRIC-60s (Biological Research In Canisters). We report here on the morphological characteristics of: (1) the recovered flight plants (N =177), (2) the corresponding ground control population (N =183), plus (3) additional controls grown on the ground under clinostat conditions (N =93). No significant morphological differences were found between the flight, ground control and clinorotated treatments for either the cotyledons or hypocotyls. There were, however, significantly longer primary roots produced in the flight population relative to the ground control population, which in turn had significantly longer primary roots than the clinorotated population. This same pattern was observed relative to the production of lateral roots (flight>control>clinorotated). Taken together with previous literature reports, we believe that there is now sufficient evidence to conclude that plants grown under conditions of microgravity will generally exhibit enhanced root production relative to their ground control counterparts. Some causes underlying this phenomenon are speculated on. [Copyright &y& Elsevier]

Abstract: The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle physics experiment that will study cosmic rays in the ∼100MeV to 1TeV range and will be installed on the International Space Station (ISS) for at least 3 years. A first version of AMS-02, AMS-01, flew aboard the space shuttle Discovery from June 2 to June 12, 1998, and collected 108 cosmic ray triggers. Part of the Mir space station was within the AMS-01 field of view during the four day Mir docking phase of this flight. We have reconstructed an image of this part of the Mir space station using secondary π− and μ− emissions from primary cosmic rays interacting with Mir. This is the first time this reconstruction was performed in AMS-01, and it is important for understanding potential backgrounds during the 3 year AMS-02 mission. [Copyright &y& Elsevier]

Abstract: The explosion of space shuttle Columbia on 1 February 2003 shocked the nation and threatened to destroy the image and confidence NASA had labored years to restore in the wake of its poor handling of the Challenger disaster. This paper examines NASA''s crisis communications regarding Columbia''s explosion. It argues that the space agency did most things right in responding to the crisis, but it made errors that reflect serious and long-standing problems with its organizational culture. The paper concludes that NASA''s handling of the crisis ultimately helped the agency to maintain good will with Congress, the media, and the American public. It proposes that the space agency must fix flaws with its organizational culture, or it may be forced into the unenviable position of relying on crisis communications to protect its image and reputation. [Copyright &y& Elsevier]

Solid-waste treatment in space for Advanced Life Support, ALS, applications requires that the material can be safely processed and stored in a confined environment. Many solid-wastes are not stable because they are wet (40–90% moisture) and contain levels of soluble organic compounds that can contribute to the growth of undesirable microorganisms with concomitant production of noxious odors. In the absence of integrated Advanced Life Support systems on orbit, permanent gas, trace volatile organic and microbiological analyses were performed on crew refuse returned from the volume F “wet” trash of three consecutive Shuttle missions (STS-105, 109, and 110). These analyses were designed to characterize the short-term biological stability of the material and assess potential crew risks resulting from microbial decay processes during storage. Waste samples were collected post-orbiter landing and sorted into packaging material, food waste, toilet waste, and bulk liquid fractions deposited during flight in the volume F container. Aerobic and anaerobic microbial loads were determined in each fraction by cultivation on R2A and by acridine orange direct count (AODC). Dry and ash weights were performed to determine both water and organic content of the materials. Experiments to determine the aerobic and anaerobic biostability of refuse stored for varying periods of time were performed by on-line monitoring of CO2 and laboratory analysis for production of hydrogen sulfide and methane. Volatile organic compounds and permanent gases were analyzed using EPA Method TO15 by USEPA et al. [EPA Method TO15, The Determination of Volatile Organic Compounds (VOCs) in Ambient Air using SUMMA, Passivated Canister Sampling and Gas Chromatographic Analysis, 1999] with gas chromatography/mass spectrometry and by gas chromatography with selective detectors. These baseline measures of waste stream content, labile organics, and microbial load in the volume F Shuttle trash provide data for waste subsystem analysis and atmospheric management within the ALS Project. [Copyright &y& Elsevier]

This paper describes observations and analyses of meteoroid and debris impact damage to the Space Shuttle Orbiter over the past decade. Since 1992, NASA Space Shuttle Orbiter post-flight inspection procedures have been altered to allow systematic identification and sampling of meteoroid/debris impacts in selected areas of the vehicle. These areas include the crew module windows and radiator panels that line the interior of the payload bay doors. In addition, other significant impact damage is identified and sampled on other critical surfaces or exposed structures such as wing leading-edge panels, external thermal-protection materials, radiator interconnect lines, and Ku-band antenna components. Samples of the impact damage are obtained and subjected to scanning electron microscope energy dispersive X-ray analysis to determine elemental composition of impactor materials recovered from the impact site. Based on these results, the source of the impact damage is categorized as meteoroid or debris, and debris particle types are identified. Historical trends indicate a large variability in debris impact rates from mission-to-mission with higher impact rates than average occurring more regularly since 1998. Predictions of post-flight damage are compared to observed damage using BUMPER code and as-flown attitude timelines. [Copyright &y& Elsevier]

During the quarter-century that Technology in Society has been published, great strides have been made in planetary exploration and space flight in near-Earth orbit, both with robotic spacecraft and with piloted space vehicles. Robotic spacecraft have visited every planet in the solar system and several hundred people have been in space learning how to live and work in that environment. The International Space Station is well on the way to completion and the Earth-orbiting “Great Observatories” have unlocked many of the secrets of the universe. There have also been great difficulties. Management failures have caused delays and cost increases in several major programs. Two of the five space shuttles, Columbia and Challenger, have been lost, at the cost of 14 human lives. NASA has not found a focus for its efforts around which the resources to operate a successful space exploration enterprise can be mobilized. Suggestions to remedy NASA’s management and programmatic problems are made in this paper. [Copyright &y& Elsevier]

The development of space food has been evolving since the Soviet cosmonaut, German Titov, became the first human to eat in space in August 1961. John Glenn was the first American to consume food, applesauce, on the third manned Mercury mission in August 1962. Before these events, there was no knowledge that humans would be able to swallow and, hence, eat in weightlessness. Space food development began with highly engineered foods that met rigid requirements imposed by spacecraft design and short mission durations. Improvements in the habitability of the spacecraft have permitted improvements in the quality of space food. As the missions became longer, the need for better nutrition, more variety, and easily consumable foods also became more important. Currently, the International Space Station astronauts have a wide variety of foods. The goal is to provide acceptable foods that taste similar to foods we eat here on Earth. Extended planetary stays will require even more variety and more technologic advances. Plants will be grown to recycle the air and water and will provide food for the crew. These harvested crops will need to be processed into safe, healthy, and acceptable food ingredients that can then be prepared into menu items. [ABSTRACT FROM AUTHOR]

An on-line, gas-monitoring system was developed to replace the older systems used to monitor for cryogenic leaks on the Space Shuttles before launch. The new system uses a mass spectrometer to monitor multiple locations on the Orbiter. The results of performance tests are reported in this article. [Copyright &y& Elsevier]

The chapter describes the human and environmental factors that dictate the way that displays must be designed for, and used in space. A brief history of the evolution of such display systems covers developments from the Mercury rockets to the International Space Station. [Copyright &y& Elsevier]

Human space missions have shown that human spaceflight is associated with a loss of body protein. Specific changes include a loss of lean body mass, decreased muscle mass in the calves, decreased muscle strength, and changes in plasma proteins and amino acids. The major muscle loss is believed to be associated with the antigravity (postural) muscle. The most significant loss of protein appears to occur during the first month of flight. The etiology is believed to be multifactorial with contributions from disuse atrophy, undernutrition, and a stress type of response. This article reviews the results of American and Russian space missions to investigate this problem in humans, monkeys, and rats. The relationship of the flight results with ground-based models including bedrest for humans and hindlimb unweighting for rats is also discussed. The results suggest that humans adapt to spaceflight much better than either monkeys or rats. [ABSTRACT FROM AUTHOR]