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Clothing supply has been examined for historical, current, and planned missions. For STS, crew clothing is stowed on the orbiter and returned to JSC for refurbishment. On Mir, clothing was supplied and then disposed of on Progress for incineration on re-entry. For ISS, the Russian laundry and 75% of the US laundry is placed on Progress for destructive re-entry. The rest of the US laundry is stowed in mesh bags and returned to earth in the Multi Purpose Logistics Module (MPLM) or in the STS middeck. For previous missions, clothing was supplied and thrown away. Supplying clothing without washing dirty clothing will be costly for long-duration missions. An on-board laundry system may reduce overall mission costs, as shown in previous, less accurate, metric studies. Some design and development of flight hardware laundry systems has been completed, such as the SBIR Phase I and Phase II study performed by UMPQUA Research Company for JSC in 1993.

The relationship between the duration and location of a manned space mission and significant life support resource costs is considered. These costs include mass, pressurized volume, energy, cooling and manpower. They are converted to common mass units (equivalent mass), and the probable range of values addressed. R&D and fabrication costs are hard to estimate and are not considered here, nor are any political constraints. With high equivalencies (e.g., cheap power), the relative effect of equipment mass is increased and in consequence the cost-effectiveness of bioregenerative life support rises dramatically.

The ALS Metric is the predominant tool for predicting the cost of ALS systems. Metric goals for the ALS Program are daunting, requiring a threefold increase in the ALS Metric by 2010. Compounding the problem is the slow rate new ALS technologies reach the maturity required for consideration in the ALS Metric and the slow rate at which new configurations are developed. This limits the search space and potentially gives the impression of a stalled research and development program. Without significant increases in the state of the art of ALS technology, the ALS goals involving the Metric may remain elusive. A paper previously presented at his meeting entitled, “Managing to the metric: An approach to optimizing life support costs.” A conclusion of that paper was that the largest contributors to the ALS Metric should be targeted by ALS researchers and management for maximum metric reductions.

Three distinct food system paradigms have been envisioned for long-term space missions. The Skylab, Mir and ISS food systems were based on single-serving prepackaged foods, ready to rehydrate and heat. Bioregenerative food systems, derived from crops grown and processed at the planetary station, have been studied at JSC and KSC. The US Antarctic Program’s Amundsen-Scott South Pole Base uses the third paradigm: bulk packaged food ingredients delivered once a year and used to prepare meals on the station. The packaged food ingredients are supplemented with limited amounts of fresh foods received occasionally during the Antarctic summer, trace amounts of herb and salad crops from the hydroponic garden, and some prepackaged ready to eat foods, so the Pole system is actually a hybrid system; however, it is worth studying as a bulk packaged food system because of the preponderance of bulk packaged food ingredients used.

Work defining advanced life support (ALS) technologies and evaluating their applicability to various long-duration missions has continued. Time-dependent and time-invariant costs have been estimated for a variety of life support technology options, including International Space Station (ISS) environmental control and life support systems (ECLSS) technologies and improved options under development by the ALS Project. These advanced options include physicochemical (PC) and bioregenerative (BIO) technologies, and may in the future include in-situ-resource utilization (ISRU) in an attempt to reduce both logistics costs and dependence on supply from Earth. PC and bioregenerative technologies both provide possibilities for reducing mission equivalent system mass (ESM). PC technologies are most advantageous for missions of up to several years in length, while bioregenerative options are most appropriate for longer missions. ISRU can be synergistic with both PC and bioregenerative options.