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High quality rivet installation is of critical importance to the aerospace industry, and the existence of gaps between the rivet head and the countersink is undesirable. Detection of gaps traditionally involves sectioning through rivet joints. Two concerns exist for this method of evaluation: it provides data only from the sectioned plane, and it has potential to alter the gaps. X-ray computed tomography (CT) was used to validate the effectiveness of the tradition sectioning method. It was revealed that the sectioning process generally increased the size of gaps. CT images also revealed that the gaps are not necessarily uniform around the rivet.

The High Speed Civil Transport (HSCT) will be exposed to elevated temperatures during Mach 2.4 supersonic flight. While not as extreme as those encountered in other high speed flight efforts (NASP, Shuttle), thermal effects will impact decisions in almost all areas of material selection and design. Accurate temperatures are required to evaluate materials, structural concepts, cooling requirements, etc. Analyses show the importance of structural configuration, use of fuel as a heat sink, and surface properties on structural temperatures. Capability to accurately determine convection and radiation boundary conditions is important for future HSCT design.

A series of flight tests over the ocean of a four engine turboprop airplane in the cruise configuration have provided a data set for improved understanding of wake vortex physics and atmospheric interaction. An integrated database has been compiled for wake-characterization and validation of wake-vortex computational models. This paper describes the wake-vortex flight tests, the data processing, the database development and access, and results obtained from preliminary wake-characterization analysis using the data sets.

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.

During the commercial aircraft assembly process, many interrelated installations require alignment to a common reference centerline or location to a common reference plane. A rotational laser can be used to establish a vertical, horizontal, or other desired plane orientation to serve as a common installation reference for multiple assemblies. The cargo floor installation in the lower lobe of the 777 forward section requires that three physically separate cargo floor sections be aligned to a common centerline and lie in the same horizontal plane. Two rotational lasers are used in conjunction with laser positioning equipment, digital laser targets, and conventional tooling hardware to meet the installation criteria and provide a reliable, repeatable process.

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.

Capacitance sensing probes have been in use for a number of years in the airframe assembly industry for characterizing diameters in straight and tapered fastener holes. A new type of capacitance probe was recently developed that simultaneously characterizes the countersink and shank diameters in holes drilled for index head rivets. The probe design and a unique methodology for a systems approach to qualifying a multi-probe inspection facility are presented in this paper.

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.