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The Department of Defense has made progress in modernizing its procurement of weapon systems. Modernization has identified a need to address Federal and military standards and specifications for parts, materials, and processes that represent many de facto national standards. The aerospace industry is proposing a transition to commercial specifications that meet the needs of Acquisition Reform. This paper reviews the history and benefits of modernization and describes the transition process.

Making TRANAIR an easier to use wing design tool is an important step toward reducing wing design cycle time. This paper shows the accuracy of TRANAIR in analysis mode for complex configurations with attached flow. This accuracy allows the design part to correctly predict improvements due to design changes. We show the current steps required for the MultiPoint (MP) design version of TRANAIR and the state of refinements toward increasing ease-of-use of this system. Finally, we discuss some of the proposed ways to further improve how the user interacts with the TRANAIR system for MP design.

A palladium catalytic oxidizer is being developed to remove plant-generated oxygen from a closed plant growth chamber, replacing the oxygen with carbon dioxide gas and water vapor. The device will provide a relatively simple means of preventing oxygen build-up within the chamber. It may also be used to simulate man-in-the-loop at whatever scale is desired. Discussion is provided on how the device fits in with the development of the closed plant growth environmental chamber in the short term and with controlled ecological life support systems (CELSS) development in the longer term. Alternative means of oxygen removal are compared. The results of preliminary kinetics testing is presented.

The purpose of the Permeable Membrane Experiment is to gather flight data on three areas of membrane performance that are influenced by the presence of gravity. These areas are: (1) liquid/gas phase separation, (2) gas bubble interference with diffusion through porous membranes and (3) wetting characteristics of hydrophilic membrane surfaces. These data are important in understanding the behavior of membrane/liquid/gas interfaces where surface tension forces predominate. The data will be compared with 1-g data already obtained and with predicted microgravity behavior. The data will be used to develop designs for phase separation and plant nutrient delivery systems and will be available to the life support community for use in developing technologies which employ membranes. A conceptual design has been developed to conduct three membrane experiments, in sequence, aboard a single Complex Autonomous Payload (CAP) carrier to be carried in the Shuttle Orbiter payload bay.

Future lunar science and exploration missions will involve the use of pressurized rovers for long duration lunar surface missions. Designs for pressurized rovers are being studied by NASA and the industry. This paper presents some results of work currently underway on the development of a rover simulator in the context of a new pressurized rover concept. A motion base simulator will play a vital role in generating rover vehicle design and performance requirements. A simulator based on a modular simulation (MODSIM) architecture, has been under study and development since 1991. The MODSIM approach will provide benefits of flexibility of modification, low cost, phased scheduling and ease of supportability when compared with more traditional simulator architectures. A lunar rover simulator based on MODSIM will help rover vehicle engineers to be productive through all phases of simulator development.

This paper describes the current USL outfitting with design and development changes incorporated during the past year. The International Space Station (ISS) USL is outfitted with eleven systems racks, an optical quality nadir window for earth viewing experiments and accommodations for thirteen International Standard Payload Racks (ISPRs). International payloads utilize this outfitting in a “shirt sleeve” environment by sharing allocated system resources and flight crew time to perform long term microgravity experiments. Recent changes in Command and Data Handling, 120 Vdc power, liquid and air cooling, audio and video communication, space vacuum and microgravity systems resources are included. User interfaces, systems performance and environmental conditions, in addition to the ISS USL outfitting configuration, are also updated in this ICES paper.

This paper describes the current United States Laboratory (USL) outfitting following the transition from Space Station Freedom to International Space Station (ISS). The ISS USL is outfitted with eleven systems racks, an optical quality nadir window for earth viewing experiments and accommodations for thirteen International Standard Payload Racks (ISPRs). The international payloads utilize this outfitting in a “shirt sleeve” environment by sharing allocated system resources and flight crew time to perform long term microgravity experiments. These systems resources include Command and Data Handling, 120 Vdc power, liquid and air cooling, audio and video communication, space vacuum and location dependent levels of microgravity. The ISS USL outfitting configuration, user interfaces, systems performance and environmental conditions are included in this ICES paper.

The aerospace industry uses flexible complex contoured structure in aircraft. To take advantage of advancements in engineering design, assembly methods, and inspection tools, the dimensional requirements for this kind of structure can be specified using Geometric Dimensioning and Tolerancing (GD&T) per ASME Y14.5M-1994, “Dimensioning and Tolerancing.” The 1994 revision of this standard includes some new features which can be used to specify the dimensional requirements for flexible complex contoured structure, but there are no examples on how GD&T can or should be applied. This paper gives some examples how GD&T can be applied on flexible complex contoured structure and how this usage specifies the dimensional requirements for such parts.

A liquid/gas separator called the Mostly Liquid Separator (MLS) has been devised to provide liquid/gas separation with soapy fluids in a microgravity environment, and is an integral component of the International Space Station Water Processor. Now in its third generation of development, this paper describes the evolution of the MLS design, and presents a discussion of the development test data and results.

The purposes of an airplane checklist are to (1) help the pilot and copilot ensure that the airplane is configured correctly before each phase of flight and (2) facilitate the management of nonnormal conditions. The use of a checklist has been essential in standardizing aircrew procedures. In 1996, Boeing will introduce the world's first airline-modifiable electronic checklist system on the Boeing 777 flight deck. Its design specifically addresses many traditional paper checklist problems associated with crew errors. Directed by airline design requirements, Boeing used a consistent, pilot-oriented flight deck philosophy to address the pilot interface, system functionality, and automation tradeoff questions.

Structural safety is an evolutionary accomplishment, and attention to detail design features is key to its achievement. A multitude of design considerations is involved in ensuring the structural integrity of Boeing jet transports that have common design concepts validated by extensive analyses, tests, and three decades of service. The active service life of commercial airplanes has increased in recent years as a result of increasing costs for fleet replacements. As airplanes approach their design service objectives, the incidences of fatigue and corrosion may become widespread. Continuing airworthiness of the aging jet fleet requires diligent performance from the manufacturer, the airlines, and airworthiness authorities. This paper gives an overview of traditional Boeing maintenance-related activities, joint industry/airworthiness authority initiatives, and the anticipated benefits for future generations of commercial airplanes.

At the 1990 Annual Aerospace/Airline Plating and Metal Finishing Forum, The Boeing Commercial Airplane Group presented information on boric acid/sulfuric acid anodizing (BSAA) as a replacement for chromic acid anodizing (CAA) to meet environmental regulations. This paper presents an update on the BSAA process and the status of production implementation. Background information will be reviewed including environmental issues and modifications of CAA to meet current EPA regulations. The results of BSAA process optimization, corrosion protection performance and compatibility with aircraft finishing will be given. Production implementation experience such as process control and facility requirements, including the status of BSAA for MIL-A-8625, Type IC (Anodizing, Non-chromic Acid, Meeting Type I Requirements) usage will be reviewed.

This paper addresses the steps and processes to create a full life circle of Tool Routines utilizing 3D data analysis as the driver. The paper covers the development of 3D Tool Routines for automation, the execution of the routines and the analysis of the collected historical 3D data. The process goal is to reduce the tool routine frequency by establishing and proving tool stability utilizing historical data. The historical data will also give us information in regards to design and tolerance capabilities. Graphical software programs are evolving in a way that enables us to link the different operations and software programs that encompass tool routines. Through the use of software and hardware such as laser tracker, we can achieve automation of tool routines and analysis. Customers in the aerospace, automotive and construction industries are among the beneficiaries in the application of this inspection process.

Most commercial aircraft interior panels are constructed of honeycomb cored composite sandwich panels. The panels are conventionally joined using metal brackets fastened with screws. Over the past decade, most major interior fabricators have been in transition to a method of joinery using bonded interlocking joints. This method has recently been adopted by Boeing, and is known here as Tab and Slot Joinery. These interlocking joints are defined and illustrated. The history of the development effort is outlined. Design considerations are developed. Test programs are described, including a designed experiment and a special case fatigue test. Advantages of this new joinery method over the conventional are shown.

This paper describes the evolution of the Thermal Diffusing Apparatus (TDA) (patent pending) and elaborates on the specific problems in bonded repair of complex composite structures. The use of composite materials in current and future aircraft presents both factory and field-level technicians with unique repair problems. Precise temperature control over the entire repair area is required if damaged composite aircraft structures are to be restored to mission-ready status. The TDA uniformly heats thermally complex components and is a direct replacement for conventional heat blankets, resulting in significant improvements in the repair process and better control of variations in cure temperature.

The Accurate Fuselage Panel Assembly Cell (AFPAC) is a semi-automated process that was developed for accurately assembling fuselage panels on the Boeing 757 model line. This method of assembly (prior to automatic fastening) uses a new generation, accurate CNC machine tool in conjunction with reconfigurable part fixturing techniques and specialized end-of-arm tools (end effectors). These end effectors drill coordination holes in detail parts and the skin, and trim the periphery of the skin. Machine control data (MCD) for positioning the machine tool and other subsystems are developed directly from the engineering digital definition (CATIA datasets). Reconfigurable part holding and feeding mechanisms are used to allow for product changes and reduce the overall cost of the workcell. This paper describes the AFPAC assembly system and how it compares with the traditional concept of fuselage panel assembly.

The Automated Spar Assembly Tool (ASAT II) at the Everett, Washington, 777 Boeing manufacturing facility could be the largest automated fastening cell in the commercial aircraft industry. Based on the success of the ASAT I, Boeing's 767 spar assembly tool, the 285-foot long ASAT II cell was needed to accurately position and fasten the major spar components (chords and web), then locate and fasten over 100 components (ribposts and stiffeners) to assemble the 777 forward and rear wing spars. From its inception in 1990 to the first drilled hole in January 1993 and through two years of spar production, the more advanced ASAT II has proven to be a greater success than even its 767 ASAT I predecessor. This massive automated fastening system consistently provides accurate hole preparation, inspection, and installation of three fastener types ranging from 3/16 inches to 7/16 inches in diameter.