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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 novel method for improving the accuracy and lowering the cost of large NC drilling machines has been developed. The method employs a 3D tracking interferometer measurement system to measure and correct the position of the machine end-effector prior to each drill operation. This method eliminates many geometric and thermal errors inherent to NC drilling machines. The paper discusses the background, theory, initial implementation, test results and future enhancements of the method.

Implementation of a high speed drill motor with solid carbide drill bits, along with careful attention to all details of the process, has resulted in an extraordinary increase in drill bit life, as well as improvements in cycle time and hole quality. During the implementation of a new wing panel riveting machine for use on the 737NG and 757 models a major goal was to significantly improve the drilling process. The phase out of Freon™ as a coolant/lubricant on existing machines forced changes to the drilling process, which resulted in a significant reduction in drill life, from an average of approximately 1,500 holes per drill to 305 holes. The new process on the new machine has increased the average drill life 11,375% to over 35,000 holes, decreased the drill cycle time by 80%, and improved hole quality.

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.

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.

With the increasing shift toward automation with respect to fastener installation, the need has evolved for clearer definition of the process capability of new fastener installation automation systems. In light of Engineering design requirements, and to address the process capability issue, Boeing has developed and implemented D6- 56617, a machine certification process for automated fastening of fuselage structure. This philosophy was a new approach in the following ways: 1. Previously, engineering oversight of automated fastening systems was limited to wing structure applications. 2. The process requires that process capabilities and performance of the automated machinery itself be established by test. 3. The process requires that detailed Process Control Documents be developed and followed. 4. The process links the statistical test data to the day to-day operating parameters of the machine.

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.

Adaptive control enables more productive use of high speed numerically controlled milling machines. With adaptive control, machines are programmed for optimum material removal, with the controller automatically reducing the material feed rate when heavy load conditions are encountered. The authors outline advantages of adaptive control and describe their testing technique for determining appropriate values for making maximally effective use of adaptive control.

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.