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This paper describes the continued development of a membrane-based subsystem designed to recover up to 99.5% of the water from various spacecraft waste waters. Specifically discussed are 1) the design and fabrication of an energy-efficient reverse-osmosis (RO) breadboard subsystem; 2) data showing the performance of this subsystem when operated on a synthetic wash-water solution-including the results of a 92-day test; and 3) the results of pasteurization studies, including the design and operation of an in-line pasteurizer.

Glass fabric composites have important applications in pipes, aircraft, and spacecraft structures, including microwave transparent structures, impact-resistant parts of the wing, fuselage deck and many other load-bearing structures.

In spaceflight operations, the training a crewmember receives on responding to onboard emergencies is of utmost importance. In a high-stress, high-adrenaline situation, crewmembers will have to rely heavily on the training they have received to properly execute the correct procedural response. Working within multiple constraints, NASA instructors have developed and continuously fine-tuned the emergency response training in an effort to make it both as efficient and effective as possible.

This paper presents a Military Space Plane design concept. While the current military space plane activity is focused on rocket-powered concepts, the concept presented here is powered by a rocket-based combined cycle engine that uses both rocket and air-breathing engine cycles. The design concept is the reference SSTO design concept used in the NASA HRST ANSER study. The reference concept is a derivative of the NASA air-breathing Access to Space study SSTO design concept. The Access to Space air-breathing vehicle's combined cycle engine was replaced by the Aerojet rocket-based combined cycle engine. The orbital performance capability of the reference design concept is presented for 100 n mi., polar, and 225 n mi., 51 deg. orbits. The sensitivity of GTOW to payload and margin is also presented.

A miniature quadrupole mass spectrometer array and gas chromatograph have been designed and built for NASA flight missions. Without the gas chromatograph the mass spectrometer is to be used for detection, by astronauts in EVA, of N2, O2, the hydrazines, and NH3 leaks in the hull of the International Space Station, and of adsorbed hydrazines on the astronauts’ suits. The fully-adapted astronaut system, with all software and visual readout, is called the Trace Gas Analyzer. When interfaced with the miniature gas chromatographic system, the mass spectrometer will be useful for a variety of NASA missions involving more complex gas mixtures. The missions include planetary exploration (to Venus, Europa, Titan, etc.), as well as cabin-air monitoring for long-duration human flight to the Moon, Mars, and beyond.

Current spacesuit life support systems use consumable absorbents for carbon dioxide and odor control, condensing heat exchangers and high-speed rotary separators for humidity control, and easily-contaminated water-ice sublimators for waste heat removal, resulting in complex hardware with high consumables/power usage and maintenance. The Mobile Liquid Venting Membrane Separator (VMS) performs these life support functions with low logistics penalties. It exploits pressure-swing absorption and temperature-controlled evaporation to transport carbon dioxide, humidity, odor, and waste heat to space vacuum. The Mobile Liquid VMS removes carbon dioxide, humidity, and odors from air by absorption into a hydrophilic liquid circulating around a solvent loop. Waste heat is transferred from thermal sources into the solvent loop through a heat exchanger.

This paper describes a model-based approach to diagnosing electrical faults in electrical power systems. Until recently, model-based reasoning has only been applied to physical systems with static, persistent states, and with parts whose behavior can be expressed combinatorially, such as digital circuits. Our research is one of a handful of recent efforts to apply model-based reasoning to more complex systems, those whose behavior is difficult or impossible to express combinatorially, and whose states change continuously over time. The chosen approach to representation is loosely based on the idea of the equation network proposed in [6]. This requires a more complex component and behavior model than for simpler physical devices. The resulting system is being tested on fault data from the SSM/PMAD power system breadboard being developed at NASA-MSFC [9].

A vehicle capable of transferring human crews, modules, rovers, and logistics to and from the moon already exists; it is the International Space Station (ISS). The Station’s orbit can be modified to include the moon at one focus and Earth at the other. At that point, ISS will stay in Earth-moon orbit indefinitely. Exploration crews will ride ISS to the moon where they will drop to the surface or remain in lunar orbit. Robotic explorers and surface and logistics modules will be transported to the moon the same way, while samples will be returned to Earth by the reverse process.

Serviceable spacecraft fluid systems require component designs that facilitate on-orbit maintenance. In response to this need, Moog has developed a modular fluid interface utilizing a unique disconnect technology that has improved performance characteristics such as reliability, safety, pressure drop and spillage.

This paper reports on a maintenance and reliability simulation program recently put into operation at Douglas Aircraft Company, instigated by the NASA-Langley study for Manned Orbital Research Laboratory, (MORL). The program has some features which should be of interest to the aerospace industry in general, and in particular, those companies concerned with space travel and space station inflight maintenance problems. The program has been used to yield valuable information about queue lengths, maintenance time, trade-off analysis of reliability versus spare weight, crew size, and mission length. The paper discusses the Monte Carlo methods used, the program logic, and special features that distinguish this program.

A CELSS has been defined based on current or near-term technology. The CELSS was sized to support the metabolic load of four people on the Moon for ten years. A metabolic load of 14 MJ/person/day is assumed, including an average of 2.6 hr of EVA/person/day. Close to 100% closure of water, and oxygen, and 85% closure of the food loop is assumed. With 15% of the calories supplied from Earth, this should provide adequate dietary variety for the crew along with vitamin and mineral requirements. Other supply and waste removal requirements are addressed. The basic shell used is a Space Station Freedom 7.3 m (24 ft) module. This is assumed to be buried in regolith to provide protection from radiation, meteoroids, and thermal extremes. A solar dynamic power system is assumed, with a design life of 10 years delivering power at 368 kWh/kg. Initial estimates of size are that 73 m2 of plant growth area are required, giving a plant growth volume of about 73 m3.

Although full-scale tests are more believable because they mimic actual spacecraft conditions, they are expensive and time consuming. The spiral orbit tribometer compromises between the two extremes.

Spacecraft designs incorporating a propulsion system powered by a more efficient fuel would greatly reduce the oxidizer to payload ratio. ...In this presentation, a revolutionary new vehicle is proposed that incorporates silane-based fuels into an air-breathing spacecraft design that achieves orbit via low ascent angles, where it then switches to onboard oxidizer.

The need for higher performance and long-life cryogenic cooling system, along with already stringent requirements for vibration, compactness, and mass, is self evident in spacecraft instruments especially for long space missions. It is therefore an object of this study to provide a system that has the potential to meet these challenges.

The author illustrates the scientific bases and experimental results of a solar energy collector, which has characteristics enabling it to collect the energy of the sun at a temperature high enough for modern heat engines. This absorber, whose basic part consists of a honeycomb structure, has the property to let the solar energy pass through, and to stop nearly completely the reradiation of the collected thermic energy. It is light and easily packaged in small volume and, therefore, fits space vehicles, for which the only energy available is solar energy. On earth, its possible low cost might make it economically competitive with the traditional sources of energy.

A new heat carrier for thermal management of spacecrafts, nanofluid, was prepared by suspending nanoscaled copper particles in the conventional process fluid.

The determination of a proper time step for transient analysis using CINDA, SINDA or MITAS can be a serious problem. Too large a time step can cause serious errors; too small a time step can be expensive for large thermal networks. There was no simple method to determine proper time steps and the resulting accuracy prior to the development of the subroutine FBECHK by J. T. Skladany and F. A. Costello. This paper describes a new method incorporating the theory of FBECHK into a new execution routine that is more efficient and can accurately consider discrete changes in heating due to such events as solar eclipses and thermostatic switching of heaters.

This paper describes an innovative design of a new biofiltration test lab for investigating the capability of biofiltration process for removal of ersatz multi-component gaseous streams representative of spacecraft contaminants released during long-term space travel. The lab setup allows a total of 24 bioreactors to receive identical inlet waste streams at stable contaminant concentrations via use of permeations ovens, needle valves, precision orifices, etc.

In order to build spacecraft thermal models and to compute temperatures, Alcatel Cannes uses a complete and coherent software chain: CORATHERM.

A new method is developed for calculating the low energy neutron flux in a space environment which is protected from galactic cosmic rays (GCR) and solar particle events (SPE) by shielding materials. Our calculations are compared with low energy neutron flux flight data recorded on four different STS low earth orbit missions. We also compare our neutron flux calculations with the low energy neutron flux data recorded by MIR. The low energy neutron flux calculations can be described as a deterministic method for solving the Boltzmann equation for the light ion flux associated with a given environment. Existing Monte Carlo neutron flux simulations associated with the MIR and ISS space stations are also compared with our deterministic method for calculating neutron flux.