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Journal Article

CFD Study of Ventilation and Carbon Dioxide Transport for ISS Node 2 and Attached Modules

2009-07-12
2009-01-2549
The objective of this study is to evaluate ventilation efficiency regarding to the International Space Station (ISS) cabin ventilation during the ISS assembly mission 1J. The focus is on carbon dioxide spatial/temporal variations within the Node 2 and attached modules. An integrated model for CO2 transport analysis that combines 3D CFD modeling with the lumped parameter approach has been implemented. CO2 scrubbing from the air by means of two ISS removal systems is taken into account. It has been established that the ventilation scheme with an ISS Node 2 bypass duct reduces short-circuiting effects and provides less CO2 gradients when the Space Shuttle Orbiter is docked to the ISS. This configuration results in reduced CO2 level within the ISS cabin.
Journal Article

Role of Power Distribution System Tests in Final Assembly of a Military Derivative Airplane

2009-11-10
2009-01-3121
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.
Journal Article

Self-Configuring Hybrid Duct System and Attachment Technologies for Environmental Control Systems

2009-11-10
2009-01-3277
Environmental Control Systems (ECS) ducts on airplanes are primarily fabricated from aluminum or thermoset composites, depending on temperature and pressure requirements. It is imperative to fabricate lightweight, cost effective, durable, and repairable systems with minimal tooling. It is also important that the duct systems are easy to assemble even with alignment issues resulting from structural variations, tolerance accumulation, variation from thermal expansion of different materials, and inherent duct stiffness. These requirements create an opportunity and need for a technology that can address all of these issues, while increasing performance at the same time. This report provides a background on current ECS ducting systems.
Journal Article

Estimating Return on Investment for SAVI (a Model-Based Virtual Integration Process)

2011-10-18
2011-01-2576
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.
Technical Paper

International Space Station (ISS) Carbon Dioxide Removal Assembly (CDRA) Desiccant/Adsorbent Bed (DAB) Orbital Replacement Unit (ORU) Redesign

2007-07-09
2007-01-3181
The Carbon Dioxide Removal Assembly (CDRA) is a part of the International Space Station (ISS) Environmental Control and Life Support (ECLS) system. The CDRA provides carbon dioxide (CO2) removal from the ISS on-orbit modules. Currently, the CDRA is the secondary removal system on the ISS, with the primary system being the Russian Vozdukh. Within the CDRA are two Desiccant/Adsorbent Beds (DAB), which perform the carbon dioxide removal function. The DAB adsorbent containment approach required improvements with respect to adsorbent containment. These improvements were implemented through a redesign program and have been implemented on units on the ground and returning from orbit. This paper presents a DAB design modification implementation description, a hardware performance comparison between the unmodified and modified DAB configurations, and a description of the modified DAB hardware implementation into the on-orbit CDRA.
Technical Paper

Analysis and Predicted Temperature Control of Crew Quarters added to Node 2 of the International Space Station

2007-07-09
2007-01-3071
Currently scheduled to be delivered to the International Space Station (ISS) in 2009, Crew Quarters (CQs) will be installed in the Node 2 Module. The CQs provide crewmembers with private space, a place to sleep, and minimal storage. Analysis is to be performed to determine if the United States Operational Segment (USOS) Node 2 can maintain temperature between 47°C and 62°C (65°F and 80°F) [units are CCGS with U.S unit in parenthesis] within the CQ. The analysis will concentrate on the nominal hot environmental case. Environmental heat is due to solar heating of the external shell of the ISS. Configurations including both three and four CQs are examined, as well as multiple configurations of the Low Temperature Loop (LTL) that flows through the Node 2 Common Cabin Air Assembly (CCAA). This paper describes the analysis performed to determine if Node 2 will be able to maintain cabin temperature between 47°C and 62°C (65°F and 85°F).
Technical Paper

Universal Splice Machine

2007-09-17
2007-01-3782
There is an increasing demand in the aerospace industry for automated machinery that is portable, flexible and light. This paper will focus on a joint project between BROETJE-Automation and Boeing called the Universal Splice Machine (USM). The USM is a portable, flexible and lightweight automated drilling and fastening machine for longitudinal splices. The USM is the first machine of its kind that has the ability not only to drill holes without the need to deburr, (burrless drilling) but also to insert fasteners. The Multi Function End Effector (MFEE) runs on a rail system that is mounted directly on the fuselage using a vacuum cup system. Clamp up is achieved through the use of an advanced electromagnet. A control cart follows along next to the fuselage and includes an Automated Fastener Feeding System. This paper will show how this new advancement has the capabilities to fill gaps in aircraft production that automation has never reached before.
Technical Paper

Verification of Supply Chain Quality for Perishable Tools

2007-09-17
2007-01-3813
Increased emphasis on standardizing processes and controlling variability in production operations includes validating perishable tools used in daily operations. Even though dealing with reputable manufacturers, many factors including communication, custom specifications and personnel turnover can lead to the perpetuation of mistakes if errors are not discovered and corrective action implemented. However, inspection is costly and inspection costs far outweigh many item costs unless considering product defects. A beneficial balance may be obtained by employing statistical sampling techniques similar to ISO 2859 [1] to verify the quality of incoming tools.
Technical Paper

3D Re-Engineering: A Comprehensive Process for Solving Production Assembly Fit Problems

1998-06-02
981835
Dimensional Management (DM) is a methodology to predict and control the impact of variation on assembly from, fit, and function. Application of Dimensional Management tools and other modeling and simulation techniques are combined in a process called 3D Re-Engineering for application to existing production designs. Analytical techniques for predicting the impact of variation on assembly fit, and corresponding methods for controlling variation are presented, as used in a production environment for root cause corrective action on existing assembly fit problems. Assembly variation analysis is typically performed early in the product development phases, by coordinating datums, assembly sequences, assembly methods, and detail part tolerances across the product development team.
Technical Paper

Integrated Air Interchange System Performance for Early Internatonal Space Station Assembly Missions

1998-07-13
981588
A multi-element fixed control volume integrated air interchange system performance computer model has been developed and upgraded for the evaluation/assessment of atmospheric characteristics inside the crew compartments of the mated Orbiter and International Space Station (ISS). In order to ensure a safe, comfortable, and habitable environment for all the astronauts during the Orbiter/ISS docked period, this model was utilized to conduct the analysis for supporting the early ISS assembly missions. Two ISS assembly missions #2A and #4A were selected and analyzed.
Technical Paper

Friction Stir Welding-A Revolutionary New Joining Method

1998-09-15
982149
Friction Stir Welding (FSW) can achieve high quality welds in aluminum alloys that are of interest to the aerospace industry (e.g. alloys 2014, 2219, 7050 and numerous aluminum-lithium alloys). The low distortion solid-phase welds exhibit metallurgical and mechanical properties, including fatigue, which are superior to conventional fusion welds achieved by arc processes. FSW, although a relatively new welding technique, has been systematically developed and proved by The Welding Institute (TWI) under contract to an international group of sponsors, one of which is The Boeing Company. To further validate the process, The Boeing Company conducted separate development activities including detailed mechanical testing of welds made from the FSW process.
Technical Paper

Laser Tracker Assisted Aircraft Machining and Assembly

2008-09-16
2008-01-2313
The patented (US 7,277,811 B1) Position Bar provides precise measurement, machining and drilling data for large Engineering and Tooling structure. The Position Bar also supports end item verification seamlessly in the same machining control code. Position Bar measurements are fast, accurate, and repeatable. The true centerline of the machine tool's spindle bearings are being measured to within .002 in a 20 foot cubic volume (20×20×20). True “I”, “J”, & “K” machine tool spindle positions are also precisely measured. Any Gantry or Post Mill Tool can be converted to a Coordinate Measurement Machine (CMM) with this laser tracker controlled Position Bar. Determinant Assembly (D.A.) holes, for fuselage and wing structures are drilled and then measured to within .006 in X, Y, & Z, over a 40 foot distance. Average laser tracker measurement time, per hole, is 2 seconds.
Technical Paper

Modification of the USOS to Support Installation and Activation of the Node 3 Element

2009-07-12
2009-01-2416
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.
Technical Paper

Efficient Assembly Integration and Test (EAIT) Moves Theory to Practice at a System Level to Effect Lean Outcomes on the Shop Floor

2009-11-10
2009-01-3169
This paper will describe the Efficient Assembly Integration and Test (EAIT) system level project operated as a partnership among Boeing business units, universities, and suppliers. The focus is on the successful implementation and sharing of technology solutions to develop a model based, multi-product pulsed line factory of the future. The EAIT philosophy presented in this paper focuses on a collaborative environment that is tightly woven with the Lean Initiatives at Boeing's satellite development center. The prototype is comprised of a platform that includes a wireless instrumentation system, rapid bonding materials and virtual test of guidance hardware there are examples of collaborative development in collaboration with suppliers. Wireless tools and information systems are also being developed across the Boeing Company. Virtual reality development will include university partners in the US and India.
Technical Paper

Portable Fastener Delivery and Installation System

2003-09-08
2003-01-2953
The Portable Fastener Delivery System or PFDS, has been developed at the Boeing St. Louis facility to streamline the manual fastener installation process. The PFDS delivers various fasteners, on demand, through a delivery tube to an installation tool used by the operator to install the fasteners in an aircraft assembly. This paper describes the PFDS in its current configuration, along with the associated Huck® International (now Alcoa Fastening Systems) installation tooling, as it is being implemented on the F/A-18E/F Nosebarrel Skinning application. As a “portable” system, the PFDS cart can be rolled to any location on the shop floor it might be needed. The system uses a removable storage cassette to cache many sizes and types of fasteners in the moderate quantities that might be required for a particular assembly task. The operator begins the installation sequence by calling for the particular fastener grip length needed using a wireless control pendant.
Technical Paper

Post-Flight Sampling and Loading Characterization of Trace Contaminant Control Subassembly Charcoal

2003-07-07
2003-01-2487
Trace chemical contaminants produced by equipment offgassing and human metabolic processes are removed from the atmosphere of the International Space Station's U.S. Segment by a trace contaminant control subassembly (TCCS). The TCCS employs a combination of physical adsorption, thermal catalytic oxidation, and chemical adsorption processes to accomplish its task. A large bed of granular activated charcoal is a primary component of the TCCS. The charcoal contained in this bed, known as the charcoal bed assembly (CBA), is expendable and must be replaced periodically. Pre-flight engineering analyses based upon TCCS performance testing results established a service life estimate of 1 year. After nearly 1 year of cumulative in-flight operations, the first CBA was returned for refurbishment. Charcoal samples were collected and analyzed for loading to determine the best estimate for the CBA's service life.
Technical Paper

International Space Station (ISS) United States Carbon Dioxide Removal Assembly Blower Anomaly Resolution

2001-07-09
2001-01-2416
The Carbon Dioxide Removal Assembly (CDRA) is the primary carbon dioxide removal system located in the United States On-Orbit Segment (USOS) Laboratory module ‘Destiny’ and Node 3 on the International Space Station (ISS). CDRA is housed in a standard ISS rack defined as the Atmosphere Revitalization (AR) rack consisting of the CDRA, Trace Contaminant Control Subassembly and Major Constituent Analyzer. The AR subsystem operation and failure detection are controlled automatically using software that has provisions for override control. This paper will present the blower failure that was experienced during AR rack level and Laboratory ECLS integrated testing. The failure description, failure investigation findings and steps taken to return CDRA to flight will be covered.
Technical Paper

Assessment of Lithium Hydroxide Conservation Via International Space Station Control of Orbiter Carbon Dioxide

2002-07-15
2002-01-2271
In order to conserve mass and volume, it was proposed that the International Space Station (ISS) control the level of carbon dioxide (CO2) in the Space Shuttle Orbiter while the Orbiter is docked to the ISS. If successful, this would greatly reduce the number of lithium hydroxide (LiOH) canisters required for each ISS-related Orbiter mission. Because of the impact on the Orbiter Environmental Control and Life Support Subsystem (ECLSS), as well as on the Orbiter flight manifest, a Space Shuttle Program (SSP) analysis was necessary. STS-108 (ISS UF1) pre-flight analysis using the Personal Computer Thermal Analyzer Program (PCTAP) predicted that the ISS would be able to control the level of CO2 in the Orbiter (and throughout the stack) under nominal conditions with no supplemental LiOH required. This analysis assumed that the Carbon Dioxide Removal Assembly (CDRA) located in the U.S.
Technical Paper

Use of Electromagnetic and Vacuum Forces on Aircraft Assembly

2002-10-01
2002-01-2630
Decades ago our innovative grandfathers developed the first automated riveting machines based on hard automation using kinematics and tools attached to a C-frame. The C-frame serves multiple functions: First, it holds the upper and lower tools in fixed positions relative to each other; second, it translates upper active tooling forces to the lower tool; and third, it embraces the part placed between the upper and lower tool. C-frames and newly developed yoke, ring and gantry machines, used for low level (first, second) fuselage and wing assembly are growing in size to exorbitant proportions to satisfy requirements of larger and larger structures. High costs are dictated by massive kinematics and complex controls that provide stability, precision, and process speed. All this is mainly needed because we have to carry mechanical forces around the part, from upper to lower tool along the C-frame, gantry, yoke, bridge, etc.
Technical Paper

777X Control Surface Assembly Using Advanced Robotic Automation

2017-09-19
2017-01-2092
Fabrication and assembly of the majority of control surfaces for Boeing’s 777X airplane is completed at the Boeing Defense, Space and Security (BDS) site in St. Louis, Missouri. The former 777 airplane has been revamped to compete with affordability goals and contentious markets requiring cost-effective production technologies with high maturity and reliability. With tens of thousands of fasteners per shipset, the tasks of drilling, countersinking, hole inspection, and temporary fastener installation are automated. Additionally and wherever possible, blueprint fasteners are automatically installed. Initial production is supported by four (4) Electroimpact robotic systems embedded into a pulse-line production system requiring strategic processing and safeguarding solutions to manage several key layout, build and product flow constraints.
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