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Several years ago Raytheon Aircraft Production Managers were faced with four looming problems: 1. Rising medical charges due to Carpal Tunnel and related illness. 2. Rising labor costs caused by antiquated, ineffecient, ineffective assembly methods. 3. Inability to meet production schedules. 4. Inferior quality, excessive rework. The popular consensus for improvement of all of the above noted conditions was automation through machine riveting.

British Aerospace needed an automated wing riveting system for fastening the A320 wing sections. The E4000 Wing Riveting System was designed and installed at their Airbus factory in Chester, UK and is now in production. It uses a five axis solid yoke with workheads on each end of the yoke. It accurately installs both rivets and lockbolts over the entire wing panel, including offset areas.

Business case analysis of projects has become a valuable tool in the way a company makes decisions in today's manufacturing environment. The business case is an attempt to closely analyze the financial ramifications of implementing a new procedure or piece of equipment. Contained within the business case is a Return On Investment (ROI) spreadsheet, calculations, and background information.

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.

Pneumatic, manually operated, drilling machines are used to produce a significant proportion of all holes drilled during wing manufacture. Drilling machine design and the manual drilling process has not changed significantly in decades. By employing miniature, low power, electronics and interfacing techniques, a monitoring system has been developed. This system enables improved process control of the manual drilling operation. Machine calibration management, measurement of drill performance, jig drilling error control and asset management are some of the benefits attainable. This project will hopefully encourage others to discover the potential for improving historically established processes, by employing modern technological developments.

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.

A new vibration resistant collar has been developed by Huck International. This collar is suitable to be used with all pins in standard threads such as Aero-Lite manufactured by Huck or other similar products available on the market. The unique feature of this product is its capability to remain free running until it meets the sheet line. Therefore, a user can install it to finger tight, set up the whole assembly, and finish the installation with a standard torque controlled collar runner or with collar runner without torque control, depending on the user's preference with the use of corresponding type of collars. The lock will develop during installation and sufficient clamp force and tensile strength are also developed in the process. A solid round lock is developed in this collar. The developed clamp force and tensile strength is comparable to collars used in similar applications at present.

Aircraft and military ground vehicles are exposed to extreme environmental conditions, not the least of which is vibration. Safety and reliability considerations have led to a variety of locking mechanisms. Until recently, the most effective solution for securing switches, sensors, hydraulic actuators and many other external components was safety wire. A new locking washer concept has been developed that provides safety, quality and cost advantages over safety wire for many of these applications. This concept has found use in military land vehicles, helicopters and aircraft including over 400 fastening applications on the F-22 fighter.

Several assembly factors have a predictable effect on structural durability of commercial airframes. This paper will discuss the importance of fastener interference and fastener tension (preload). The impact of manufacturing tolerances on these installation factors will be reviewed, as will benefits of reducing variation and targeting the process.

The Hi-Set Fastening System is a high strength (95 KSI shear) single piece fastener used for automated airframe assembly with squeeze type assembly equipment. As the demands for improved surface quality, shorter cycle times and lower cost increase throughout the airframe industry, automated assembly is becoming more attractive. The design detaiils, installation tooling, installation sequence and cost effectiveness of the Hi-Set are reviewed and compared to other fastening systems.

Traditionally, large airframe structures have been assembled on hard tooling, a laborious unforgiving process. Beginning with the C-17, servo-assisted positioning tools have been used to enable faster fit-up, and better understanding of best fit options. Positioner technology has been used in large structure assembly for the 777, and the next-generation 737, and is now being implemented on other transport and civil aviation aircraft. While returning benefit to the airframe manufacturer in terms of improved fit-up and reduced cycle time, these systems are expensive and are not generally adaptable to change in product form or market demand. This paper provides an overview of positioner development and present status, and describes a series of options and initiatives that can make the technology less expensive, and easier to install, use, and maintain.

Throughout the years aircraft producers have struggled with the elusive goal of “Automated Assembly of aircraft structures”. This goal has been attempted in conjunction with and tempered by the basic reality of current aircraft manufacturing methodology. Automated systems have been used for years, but have almost exclusively been based on time tested technology, the derivation of which is “C Frame” riveters. There have been attempts to automatically move the panels, skins and bulkheads using CNC equipment. There have been other attempts to move the riveting head itself; however the basic premise has been a two sided fastener. There are many new technologies attempting to modify the basic paradigm, aircraft are for the most part held together by rivets. The art remains to a substantial degree unchanged.

This paper reviews today's aircraft wing production assembly methodology and technologies as well as innovative ideas for advancing the high-level wing assembly state-of-the-art. Automated wing assembly systems are only being utilized to rivet/fasten first level subassemblies like panels, spars, and ribs. All other high level assembly tasks are performed manually, incurring associated increases in recurring costs due to production inefficiencies, long lead times, expensive rate tooling, and difficult assembly tasks performed inside small wing compartments. Existing assembly methods, process parameters, and the process characteristics of manual, machine, and man/machine systems provide many opportunities for improving wing assembly.

These investigations are conducted to develop new fasteners and joining methods to reduce weight and improve fatigue life of aircraft structures. Three major modes of structural failures; fatigue, fretting and stress corrosion are discussed with recommendations for improvement. Stress coining was developed to cold work aircraft structure for fatigue improvement. Standard stress corrosion test blocks have been designed for evaluation of this failure mode. A crown flush rivet configuration has been developed that does not require head shaving after installation. Qualification tests were performed in compliance with MIL-Std-1312 to obtain FAA and military approval. Various new fasteners have been developed for aluminum, graphite-epoxy and titanium structure. These fasteners were designed to be forgiving to the hole in that they will fill and prestress the hole uniformly without being extremely sensitive to hole preparation quality.

With the increase in technical complexity of machine control systems, there is more demand than ever for field service technicians and engineers to be able to establish a remote communication link to the customer's machines for diagnostics and trouble shooting purposes. This paper will discuss current control architectures and explain Gemcor's approach to establishing remote communication to these technologies. The demonstration will explore making the connection over the Internet and direct phone lines.

This paper presents a detailed overview of the advantages and benefits of using 2-D barcodes, called Data Matrix codes, on Wing Fastening System (WFS) Tooling. This project was conducted on, but not limited to, the 777 Wing Fastening System (GEMCOR) tooling including the drills, fingers, and button dies. This paper will show how using Data Matrix codes to identify tooling will: Eliminate excessive downtime due to the operator using the incorrect tooling for a given tool setup. Reduce the cost associated with panel rework due to the use of incorrect tooling. Reduce the cost associated with excessive tool inventory or last minute ordering to keep up with production needs. Track tool life information for each specific tool. Provide operators with an easy to use tool setup reference document. And provide the factory with the ability to trace panel damage or defects back to the specific machine and exact tooling used.

As the aerospace industry approaches the 21st century, high standards of quality and the need for innovative solutions in automated fastening has prompted new developments in automated fastening equipment. Applying today's current technology to a concept created decades ago, Machine Dynamics has designed and produced an all-electric riveting machine. Utilizing roller screw technology with a servo driven motion control system, the all-electric riveter offers the power and speed heavy production demands without the use of hydraulics. This paper explains the origins of the electric riveter, the roller screw technology being applied to today's production equipment, state-of-the-art control system required and the unique features that are a direct derivative of the electric system.

The decision to use Simulation and Off-Line Programming (OLP) technology leads a manufacturing company into an expanse of long term consequences. These experiences can be very positive if the manufacturing company approaches the project correctly. This paper addresses the factors to attain success after feasibility studies are complete and a decision to pursue this technology has been made. These factors include the development of a vendor selection method, in addition to the implementation and maintenance processes vital to a thriving project. The right techniques and information can lead a company to choices that will contribute significantly to higher levels of project success.

The Automated Spar Assembly Tool or ASAT was originally developed for the Boeing 767 wing spar in the late 1970s. Since then this powerful concept has been further advanced and integrated into nearly all the current Boeing commercial wing lines. A fourth generation system, ASAT4, has been developed for the Boeing C-17 Globemaster III. ASAT4 provides an unprecedented level of flexibility in a minimum amount of floor space. Similar to ASAT3, ASAT4 consists of a vertical traveling yoke machine which straddles the spar fixtures. Two fixtures placed end to end form a system approximately 220 feet in length which is serviced by a single machine. This allows manual operations, e.g. load and unload, to be performed on one spar while the machine works in the adjacent cell. Each fixture can accept any of the six C-17 spars. Fixture reconfiguration between spars is completely automatic. The single three axis yoke machine, the E5000, travels the full system length.

Fasteners are currently being fed into automated installation machines by a variety of different devices. Once fed, the fastener often travels to the machine's installation point via a track or feed tube. Some tracks and tubes keep the fastener oriented while others allow the fastener to tumble and reorient it at the machine head. Fastener escapements, shuttles, tracks, blow tubes and injectors are all part of the overall system. Fastener grip length selection and fastener inspection devices add to the overall complexity of feeding systems. The technical paper discusses the theory and operation of each of the fastener feeding devices including; hoppers, magazines, cassettes and vibratory bowls. Support systems are covered and methods to optimize fastener feed times are presented.