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Power quality has become a subject of increased attention for electrical power systems on both commercial and military aircraft. Several power quality guidelines and specification documents exist that govern today's power system operation and the contributing characteristics of electrical load equipment. This paper presents power quality requirements for future Boeing commercial airplanes, driven by advances in aerospace applications of power electronic equipment, increased load demand and complexity, as well as new power system architectures. The influence of new equipment types on electrical system power quality is described including the effects of motor controllers, AC power converters, and large dynamic loads. The impact of power type classifications such as variable frequency AC power and multiple DC voltage levels is also discussed. Simulation results are presented to develop and validate these power quality requirements.

The International Space Station (ISS) Environmental Control and Life Support (ECLS) system includes regenerative and non-regenerative technologies that provide the basic life support functions to support the crew, while maintaining a safe and habitable shirtsleeve environment. This paper provides a summary of the U.S. ECLS system activities over the past year, covering the period of time between May 2001 and April 2002. The ISS continued permanent crew operations, with Phase 2 completion accomplished during this period. Work continued on the Phase 3 elements with Node 3 proceeding toward a final design review and the regenerative ECLS equipment proceeding into manufacturing.

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.

Solid Waste Management (SWM) requirements need to be defined prior to determining what technologies should be developed by the Advanced Life Support (ALS) Project. Since future waste streams will be highly mission-dependent, missions need to be defined prior to developing SWM requirements. The SWM Working Group has used the mission architectures outlined in the System Integration, Modeling and Analysis (SIMA) Element Reference Missions Document (RMD) as a starting point in the requirement development process. The missions examined include the International Space Station (ISS), a Mars Dual Lander mission, and a Mars Base. The SWM Element has also identified common SWM functionalities needed for future missions. These functionalities include: acceptance, transport, processing, storage, monitoring and control, and disposal. Requirements in each of these six areas are currently being developed for the selected missions.

Schedule/Cost Risk, politics, competition for capital dollars are all factors affecting our project decisions and choices. Not understanding the key elements of a project that will contribute to schedule and cost risk will invariably result in overruns that can quickly absorb the returns expected from the investment. This paper attempts to provide the project team with a model that considers some risk factor elements to assist with the selection of project alternatives and more intelligent schedule/cost estimating.

The distribution of loads between the components of a structural assembly depends not only on their dimensions and material properties but also on the stiffness of fasteners connecting the components. So, the accuracy of the finite element analysis is influenced much by the fastener representation in the model. This paper describes an approach designed specifically for joints with connected plates modeled by shell elements located at plates mid planes. The procedure is based on definition of independent components of a fastener joint flexibility, analysis of each component, and their assembly to represent a complete plate-fastener system of the joint. The proposed modeling technique differs from the traditional approach where all the connected plates are modeled coplanar. The traditional approach is based on calculating a single spring rate for a particular combination of fastener and plate properties.

Crewmember ingress of the International Space Station (ISS) before that time accorded by the original ISS assembly sequence, and thus before the ISS capability to adequately control the levels of temperature, humidity, and carbon dioxide, poses significant impacts to ISS Environmental Control and Life Support (ECLS). Among the most significant considerations necessitated by early ingress are those associated with the capability of the Shuttle Transportation System (STS) Orbiter to control the aforementioned levels, the capability of the ISS to deliver the conditioned air among the ISS elements, and the definition and distribution of crewmember metabolic heat, carbon dioxide, and water vapor. Even under the assumption that all Orbiter and ISS elements would be operating as designed, condensation control and crewmember comfort were paramount issues preceding each of the ISS Missions 2A and 2A.1.

Burr research is undeniably highly complex. In order to advance understanding of the process involved several techniques are being implemented. First a detailed and thorough examination of the burr forming process is undertaken. The technique is difficult, intricate and time consuming, but delivers a large amount of vital physical data. This information is then used in the construction of empirical models and, in some case lead to development of FEM models. Finally using the model as a template, related burr formation problems that have not been physically examined can be simulated and the results used to control process planning resulting in the reduction of burr formation. We highlight this process by discussing current areas of research being followed at the University of California in collaboration with Boeing and the Consortium on Deburring and Edge Finishing (CODEF).

This paper is an explanation of some of the Flight Test Safety (FTS) methods used to reduce the risk associated with military rotorcraft development. Two flight test programs are addressed, the V-22 Osprey tiltrotor and the RAH-66 Comanche helicopter. A short history of the development of each program is provided as background information. Some of the challenges and strengths of joint ventures are also identified and discussed. Four critical elements of an FTS program are identified: 1) Organizational Risk Management (ORM), 2) issue/anomaly resolution, 3) incident recording and corrective action documentation and 4) interface between FTS and other organizations. Methods used in the two programs to address these elements are reviewed and can be applied to other flight test programs.

This paper identifies an approach to the definition of a National Airspace System (NAS) architecture which will support the future development of the U.S. air transportation system, consistent with long-range needs of the various users of the NAS. The approach outlined identifies the development of an FAA preliminary design methodology, with supporting tools and processes to provide the basis for NAS modernization. This approach begins with the quantification of the primary long-range objectives of the NAS, which the system architecture must support over its design life. These objectives are the basis of the mission analysis and requirements development, which, in turn, are used for technology tradeoff studies and the baselining of an architecture for evaluation.

A study was conducted to investigate the impacts of obstacles on pilot performance, workload, and perceptions of safety in a visual flight rule (VFR) obstacle-rich environment (ORE). The study was conducted using a piloted simulation of a single-rotor, multi-engine helicopter operating in a highly detailed urban visual scene database. The database contained multiple obstacle types, with variable obstacle heights and densities. Nine pilots completed the approaches and departures into and out of a heliport located in the center of the generic urban environment. Two flight routes offered unique presentations of terrain and obstacle types. Obstacle height/density and time of day/lighting parameters were systematically manipulated. A multi-dimensional data collection methodology employing the simultaneous collection of direct aircraft state, pilot performance data, pilot physiological data and pilot subjective responses was employed.

A review is made of previously reported status of the augmentor wing concept, including test work of de Havilland Aircraft of Canada and the NASA Ames Research Center. More recent NASA data which formed the basis for proceeding with a flight research vehicle program on the Buffalo CV-7A are discussed. This background is used to show potential application to a turbofan-powered production airplane concept whose highly integrated propulsion and aerodynamics show promise for a very quiet STOL. Proposed future augmentor wing development programs are also briefly discussed.