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A consortium of interested parties has conducted an experimental characterization of two Tau parallel kinematic machines which were built as a part of the EU-funded project, SMErobot1. Characteristics such as machine stiffness, work envelope, repeatability and accuracy were considered. This paper will present a brief history of the Tau parallel machine, the results of this testing and some comment on prospective application to the aerospace industry.

Boeing has contracts for military application of twin engine airplanes generically identified in this paper as the MX airplane. Unlike previous derivatives, the MX airplanes are produced with a streamlined manufacturing process to improve cost and schedule performance. The final assembly of each MX airplane includes a series of integration tests, called factory functional tests (FFTs), which are modified from those of typical commercial versions and verify correctness of equipment installation and basic functionalities. Two airplanes have been through the production line resulting in a number of FFT lessons learned. Addressed are the power distribution lessons learned: 1) the expanded coverage of the basic automated power-on generation system test, 2) the need for a manual wire continuity test, 3) salient features of the power distribution tests, and 4) keys to make first pass power distribution test smooth and successful.

Computational Fluid Dynamics airflow models for the Waste and Hygiene Compartment (WHC) in the U.S. Laboratory module and Node 3 were developed and examined. The International Space Station (ISS) currently provides human waste collection and hygiene facilities in the Russian Segment Service Module (SM) which supports a three person crew. An additional set of Russian hardware, known as the system, is planned for the United States Operational Segment (USOS) to support expansion of the crew to six persons. Integration of the Russian system into the USOS incorporates direct Environmental Control and Life Support System (ECLSS) interfaces to allow more autonomous operation. A preliminary design concept was used to create a geometry model to evaluate the air interaction with the module cabin at varied locations and performance of the avionics fan placed in WHC. The Russian and the privacy protection bump-outs (Kabin) were included into the present modeling.

The System Architecture Virtual Integration (SAVI) program is a collaboration of industry, government, and academic organizations within the Aerospace Vehicle System Institute (AVSI) with the goal of structuring a new integration process that relies on a “single-truth” architectural framework. The SAVI approach of “Integrate, then Build” provides a modern distributed development environment which arrests the propagation of requirements errors through the development life cycle. It does so by capturing design assumptions and shared properties of the system design in an authoritative, annotated architectural model. This reference model provides a common, analyzable framework for confirming that system requirements remain complete, consistent, and correct at all levels of system decomposition. Core concepts of SAVI include extensive use of model-based system engineering tools and use of a “single-truth” reference architectural model.

The Shuttle retirement in 2010 will force the ISS program to reconsider how to supply the Station with nitrogen and oxygen for six to ten more years beyond 2010. The major options for post-Shuttle retirement resupply are resupply via transfer vehicle, the use of small Intervehicular Activity (IVA) high pressure tanks, “stockpile” enough gas to support International Space Station (ISS) through end of life, or generate the necessary gases onboard the Station. The method chosen to sustain the ISS will serve as a building block for producing new minimally dependent environmental control and life support systems for future manned missions to the Moon, Mars and beyond.

The development of new commercial airliners is a very risky proposition. To get it right, airframe manufacturers must balance new technologies and manufacturing methods with global participation and business considerations. The 787 is Boeing's popular new wide body aircraft incorporating state of the art composites design and manufacturing methods. But new technology alone is not enough. A new logistics system was needed to integrate global partners in order to fully benefit from new technologies. The Boeing 747-400 Dreamlifter is a special purpose 747-400 modified to transport Boeing 787 airplane components through various stages of manufacturing.

The temperature and humidity of the air within the habitable areas of the International Space Station are controlled by a set of hardware and software collectively referred to as the Temperature and Humidity Control (THC) subassembly. This subassembly 1) controls the temperature of the cabin air based on a crew selected temperature, 2) maintains humidity within defined limits, and 3) generates a ventilation air flow which circulates through the cabin. This paper provides descriptions of the components of the THC subassembly, their performance ranges, and the control approach of the hardware. In addition, the solutions of the design challenges of maintaining a maximum case radiated noise level of NC 45, controlling the cabin air temperature to within ±2°F of a setpoint temperature, and providing a means of controlling microbial growth on the heat exchanger surfaces are described.

As pieces of the International Space Station (ISS) enter their test phase, access to information and data from the test laboratories must be made immediately available to analysts, managers, and customers. The Virtual Laboratory (VLAB) concept provides remote access to laboratory test data and other information, indirectly as archived data or directly as real-time data off the test bed. We applied VLAB to a life support system hardware test (the Trace Contaminant Control System, TCCS) in the Life Support Technology Center (LSTC). In this paper we describe the VLAB concept in the context of the TCCS hardware test.

The proliferation and growth of microorganisms in the Internal Active Thermal Control System (IATCS) aboard the International Space Station (ISS) has been of significant concern since 2001. Initial testing and assessments of biocides to determine bacterial disinfection capability, material compatibility, stability (rate of oxidative degradation and identification of degradation products), solubility, application methodology, impact on coolant toxicity hazard level, and impact on environmental control and life support systems identified a prioritized list of acceptable biocidal agents including glutaraldehyde, ortho-phthalaldehyde (OPA), and methyl isothiazolone. Glutaraldehyde at greater than 25 ppm was eliminated due to NASA concerns with safety and toxicity and methyl isothiazolone was eliminated from further consideration due to ineffectiveness against biofilms and toxicity at higher concentrations.

The International Space Station (ISS) program is nearing an assembly complete configuration with the addition of the final resource node module in early 2010. The Node 3 module will provide critical functionality in support of permanent long duration crews aboard ISS. The new module will permanently house the regenerative Environment Control and Life Support Systems (ECLSS) and will also provide important habitability functions such as waste management and exercise facilities. The ISS program has selected the Port side of the Node 1 “Unity” module as the permanent location for Node 3 which will necessitate architecture changes to provide the required interfaces. The USOS ECLSS fluid and ventilation systems, Internal Thermal Control Systems, and Avionics Systems require significant modifications in order to support Node 3 interfaces at the Node 1 Port location since it was not initially designed for that configuration.

The Selective laser sintering (SLS) process offers unique capabilities for production of complex, thin-walled geometries with internal features, integral attachments and flanges. The benefits of SLS have been realized on a variety of Boeing military platforms for a number of years. However, applications on commercial aircraft have been limited by material flammability requirements. To address this gap, Boeing, in cooperation with Advanced Laser Materials, developed a flame retardant polyamide material that is now commercially available (ALM FR-106). This paper introduces the general advantages of laser sintering as applied to the manufacturing of flight hardware and a description of the development of the flame retardant material in use.

A family of water-based sol-gel coatings has been developed as an environmentally-friendly alternative to traditional aerospace finishing materials and processes. The sol-gel hybrid network is based on a reactive mixture of an organo-functionalized silane with a stabilized zirconium complex. Thin films of the material self-assemble on metal surfaces, resulting in a gradient coating that provides durable adhesion for paints, adhesives, and sealants. Use of the novel coating as a surface pretreatment for the exterior of commercial aircraft has enabled environmental, health, and safety benefits due to elimination of hexavalent chromium, and flight test and early fleet survey data support the laboratory observations that the sol gel coating reduces the occurrence of “rivet rash” adhesion failures. Modifications of the basic inorganic/organic hybrid network have yielded multifunctional coatings with promise for applications such as corrosion control and oxidation protection.

The repairing of commercial aircraft is a complex task. Service engineers at Boeing's Commercial Aviation Services group specialize in providing crucial repair information and technical support for its many customers. This paper details factors that influence Boeing's response time to service requests and how to improve it. Information pertaining to over 5000 service requests from 2008 and 2009 was collected. From analysis of this data set, important findings were discovered. One major finding is that between 6 and 8 percent of service requests are late because time/date stamps used in reports were created in a different time zone.

An air quality simulation and assessment (AQSA) model was developed to simulate/evaluate the integrated system performance and obtain air quality characteristics and air contaminants inside the habitable compartments. This model applies both fixed control volume and quasi-steady-state approach for a multi-volume system to assess system performance, operating constraints, and capabilities. The model also integrates a state-of-the-art probabilistic analysis tool, UNIPASS, to compute failure probability due to the uncertainties of variables. In addition, this integrated model also predicts the most likely outcomes for analyzing risks and uncertainties as well as for quantitative toxicological evaluation. This model has been successfully and independently corrected/verified by NASA/JSC to be a very effective, reliable, and accurate tool, while providing savings in both the cost and time of the analysis.

The International Space Station (ISS) uses high efficiency particulate air (HEPA) filters to remove particulate matter from the cabin atmosphere. Known as Bacteria Filter Elements (BFEs), there are 13 elements deployed on board the ISS's U.S. Segment. The pre-flight service life prediction of 1 year for the BFEs is based upon performance engineering analysis of data collected during developmental testing that used a synthetic dust challenge. While this challenge is considered reasonable and conservative from a design perspective, an understanding of the actual filter loading is required to best manage the critical ISS Program resources. Thus testing was conducted on BFEs returned from the ISS to refine the service life prediction. Results from this testing and implications to ISS resource management are discussed. Recommendations for realizing significant savings to the ISS Program are presented.

Choosing the best approach to meet waste processing requirements for long duration space missions should be based on objective selection criteria that provide for subsystem operational availability at the lowest mission cost. Suitable criteria would include robustness, safety, and the minimization of mass, volume, power, cooling, crew time, and resupply requirements for the candidate technologies. The best candidate technologies based on data from historical missions and preliminary data from the Solid Waste Processing and Resource Recovery Workshop (SWPRRW) have been evaluated for cost effectiveness in processing crew waste loads as defined by identified waste models. Both PC and biological approaches were considered for each of three missions: the ISS mission, a Mars transit mission, and a “concentrated exploration” mission for the Mars surface. Results of this analysis are consistent for all three missions considered.

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.

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.

This paper presents a PC based mathematical and rapid prototyping technique for anthropometric accommodation in a maintenance environment using the principle of simulation based design. The developed technique is capable of analyzing anthropometric data using multivariate (Principal component Analysis) approach to describe the body size variability of any given population. A number of body size representative cases are established which, when used properly within the constraints of the maintenance environments, will ensure the accommodation of a desired percentage of a population. This technique evaluates the percentage accommodation of a given population for the environment using the specific manikin cases as boundary conditions. In the case where any member of a maintenance crew cannot be accommodated, the technique has the capability of informing the designer of the environment why the member(s) is/are not accommodated.

Jet fighter missions have been known to last extended period of time. The need for a comfortable and safe seat has become paramount considering that fact that uncomfortable seats can lead to numerous health issues. Several health effects like numbness, pressure sore, low back pain, and vein thrombosis have been associated with protracted sitting. The cushion, and of late the installation rail angle are the only components of the ejection seat system that can be modified to reduce these adverse effects. A comprehensive static comfort evaluation study for ejection seats was conducted. It provides comparison between a variety of operational and prototype cushions (baseline cushion, honeycomb and air-cushion) and three different installation rail angles (14°, 18°, and 22°). Three operational cockpit environment mockups with adjustable installation rail angle were built. Ten volunteer subjects, six females and four males, ages 19 to 35, participated in the seat comfort evaluation.