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The Volatile organic analyzer (VOA) has been operated on the International Space Station (ISS) throughout 2002, but only periodically due to software interface problems. This instrument provides near real-time data on the concentration of target volatile organic contaminants in the spacecraft atmosphere. During 2002, a plan to validate the VOA operation on orbit was implemented using an operational scheme to circumvent the software issues. This plan encompassed simultaneous VOA sample runs and collection of archival air samples in grab sample containers (GSC). Agreement between the results from GSC and VOA samples is needed to validate the VOA for operational use. This paper will present the VOA validation data acquired through November 2002.

Space suits for advanced missions have baselined radiators as the primary means of heat rejection in order to minimize consumables and logistics requirements. While radiators have been used in the active thermal control system for spacecraft since Gemini, the use of radiators in spacesuits introduces many unique requirements. These include the ability to reduce the amount of heat rejection when overcooling or overheating of the crew member is a concern. Overcooling can occur with low metabolic rates, cold environments or a combination of the two, and overheating can occur with high metabolic rates in a warm environment. The main goal of the Radiator Advanced Demonstrator (RAD) program is to build and fly a radiator on the current Extravehicular Mobility Unit (EMU) in order to verify thermal performance capabilities in actual flight conditions. The RAD incorporates an aluminum plate separated from the primary water panel with a silicone gasket.

The Volatile Organic Analyzer (VOA) was launched to the International Space Station (ISS) aboard STS-105 in August 2001. This instrument has provided the first near real-time data on the concentrations of trace contaminants in a spacecraft atmosphere. The VOA data will be used to assess air quality on ISS in nominal and contingency situations. Until the VOA presence on ISS, archival samples that were analyzed weeks if not months after the flight were the only means to obtain spacecraft air quality data on volatile organic compounds (VOCs). Especially in contingency situations, real-time data is important to help direct crew response and measure the effectiveness of decontamination efforts. The development and certification of the VOA has been chronicled in past ICES papers. This paper will discuss the preparation of the VOA for ISS operations. Also, examples of VOA data acquired during flight will be presented to demonstrate the value of the instrument in assessing the ISS environment.

A technology project to produce a new space suit for planetary applications started in January of 1997, with a thermal vacuum test of the system, including a suited crew member, expected in the year 2000. This will be a progress report on the activities that occurred during the project's first year. The four year project is funded out of Code M at NASA Headquarters and is an effort to integrate the latest EVA technology into a maintainable modular design. The project will use as much off-the-shelf hardware as practical in an effort to lower development cost and decrease development time. Three pressurized garment configurations will be evaluated and two different portable life support systems will be built. The first year was primarily spent developing laboratories, bench-top working laboratory subsystems, analytical models, and the overall requirements and architecture of the system.

Spacecraft that must operate in cold environments at reduced heat load are at risk of radiator freezing. For a vehicle that lands at the Lunar South Pole, the design thermal environment is 215 K, but the radiator working fluid must also be kept from freezing during the 0 K sink of transit. A radiator bypass flow setpoint control design such as those used on the Space Shuttle Orbiter and ISS would require more than 30% of the design heat load to avoid radiator freezing during transit - even with a very low freezing point working fluid. By changing the traditional active thermal control system (ATCS) architecture to include a regenerating heat exchanger inboard of the radiator and using a regenerator bypass flow control valve to maintain system setpoint, the required minimum system heat load can be reduced by more than half. This gives the spacecraft much more flexibility in design and operation. The present work describes the regenerator bypass ATCS setpoint control methodology.

The Orion Crew and Service Modules are often compared to the Apollo Command and Service Modules due to their similarity in basic mission objective: both were dedicated to getting a crew to lunar orbit and safely returning them to Earth. Both spacecraft rely on the environmental control, life support and active thermal control systems (ECLS/ATCS) for the basic functions of providing and maintaining a breathable atmosphere, supplying adequate amount of potable water and maintaining the crew and avionics equipment within certified thermal limits. This assessment will evaluate the driving requirements for both programs and highlight similarities and differences. Further, a short comparison of the two system architectures will be examined including a side by side assessment of some selected system's hardware mass.