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Titanium is a difficult material to fabricate into complex configurations. There is several elevated temperature forming processes available to produce titanium components for aerospace applications. The processes to be discussed are Superplastic Forming (SPF), hot forming and creep forming. SPF uses a tool that contains the required configuration and seals around the periphery so inert gas pressure can be used to form the material. Of the processes to be discussed, this is the one that can produce the most complex shapes containing the tightest radii. A variation of the process combines an SPF operation with diffusion bonding (SPF/DB) of two or more pieces of titanium together to produce integrally stiffened structure containing very few fasteners. Another process for shaping titanium is hot forming. In this process, matched metal tools, offset by the thickness of the starting material, are used to form the part contour at elevated temperature.

The use of portable automated equipment has increased in recent years with the introduction of flex track, crawling robots, and other innovative machine configurations. Portable automation technologies such as these lower infrastructure costs by minimizing factory floor space requirements and foundation expenses. Portable automation permits a higher density of automated equipment to be used adjacent to aircraft during assembly. This equipment also allows concurrent work in close proximity to automated processes, promotes flexibility for changes in rate, build plan, and floor space requirements throughout the life of an airplane program. This flexibility presents challenges that were not encountered with traditional fixed machine drilling centers. The work zone surrounding portable machines is relatively small, requiring additional setup time to relocate and position machines near the airframe.

One of the most common damages occurred found on commercial airframes are dents and gouges. The usual repair for these damages includes installation of metallic doublers with rivets or with hi-loks. Sometimes these doublers are of complex design, because of multiple angles of the original damaged skin. Many times the damages are in hard to reach areas. In these cases the traditional metallic doubler repairs are not only time consuming and but also expensive. As the numerous holes are be drilled through the original structure, its fatigue life is adversely affected. For airline operators, time is valuable and they cannot afford to lose revenue by spending longer time for repairs. The use of bonded composite doublers offers the airframe manufacturers and aircraft repair facilities an alternative repair process that alleviates the abovementioned concerns.

Boeing needed a process to replace hand drilling for floor panel holes and galley and lavatory mounting locator holes in the floor grid of the completed 737 fuselage. Electroimpact developed a process, and the 737 AFDE machine, that is a substantial improvement over existing technology. It provides full CNC control, quick reconfiguration of hole patterns, fast drilling of up to 3000 holes in one 8-hour shift, drills both titanium and aluminum and works inside the fuselage.

The Turret Head Fastening System is an enhancement of current three position “C-frame” wing riveting machines. It was designed and built by Boeing as a fully instrumented research machine in 1991 for the 777 Airplane, and as a potential retrofit package for conventional drill, rivet, shave wing assembly machines. It was designed to automatically install rivets and bolts and perform the required hole preparation prior to fastener installation. In its current form, it will clamp a panel; and then as the fastener requires, drill, coldwork, ream, countersink the hole; inspect the hole; apply sealant when required; install threaded fasteners or rivets; torque the nut, swage the collar or upset the rivet as required; shave the rivet to ensure flushness; and finally unclamp the part - all within the current working envelope of a drill, rivet shave machine. Currently, switching from rivets to bolts requires a 5 minute tool change.

With the increasing usage of composites for aerodynamic surfaces, the use of bonded composite repair processes are becoming more common. The repair process remains a largely manual process, with repair technicians scarfing or stepping, tracing the plies, fabricating repair patches and finally bonding the patch. The patch fabrication process becomes increasingly tedious and tiring due to cutting and tracing of each individual ply twice for thermal surveying and the final repair patch. We have developed a system that can replace the tracing and cutting components of the fabrication process using low cost, commercial off the shelf (COTS) tools. We present the ply boundary extraction method used and detail the nesting algorithm used to produce the final plies. Our software is benchmarked against the manual process with a list of successfully cut materials using a low cost fabric cutter with a steel drag blade.

Integrated Vehicle Health Management (IVHM) is the unified capability of a system of systems (SoS) to assess the current or future state of the member system health, and integrate it within a framework of available resources and operational demand. As systems complexities have increased, so have system support costs, driven by more frequent and often enigmatic subsystem failures. IVHM strategies can be used to mitigate these issues by taking a Systems of Systems view. Combined with advanced decision support methods, this approach can be used to more effectively predict, isolate, schedule, and repair failed subsystems, reducing platform support costs and minimizing platform down time. Integrated Vehicle Health Management- System of Systems Integration brings together ten seminal SAE technical papers addressing the challenges and solutions to maintaining highly complex vehicles.