Search Results

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.

On Airbus aircraft, the undercarriage reinforcing is attached through the lower wing skin using bolts up to 1-inch in diameter through as much as a 4-inch stack up. This operation typically takes place in the wing box assembly jigs. Manual hole drilling for these bolts has traditionally required massive drill templates and large positive feed drill motors. In spite of these large tools, the holes must be drilled in multiple steps to reduce the thrust loads, which adds process time. For the new A380, Airbus UK wanted to explore a more efficient method of drilling these large diameter holes. Introducing automated drilling equipment, which is capable of drilling these holes and still allows for the required manual access within the wing box assembly jig, was a significant challenge. To remain cost effective, the equipment must be flexible and mobile, a llowing it to be used on multiple assemblies.

The Airbus A340-600 wing panel manufacturing system, which entered production in 1999, represents a major milestone for automated aircraft assembly. The new A340-600 system builds upon the success of the E4000 based A320 wing panel assembly system, which was introduced into production three years ago. The new A340-600 system consists of two 440 ft. assembly lines. One produces upper wing skin panels and the second produces lower skin panels. Each line consists of three fully automated CNC controlled flexible fixtures placed end to end serviced by two E4100 CNC assemble machines. Each fixture accepts multiple wing panels and can be automatically changed between the different configurations. Stringers are located and held using clamps mounted to “popping posts”. These posts automatically drop out of the machine path into the floor to provide clearance for complete stringer to skin fastening.

Most new aircraft programs encounter the challenge of balancing the time required for design optimization with product delivery constraints. The high cost and long lead times of traditional tooling makes it difficult for aircraft manufactures to efficiently meet ever-changing market demands. The large size, low relative stiffness and high positional tolerances required for aircraft components drive the requirement for rigid fixed tooling to maintain the precision part relationships over time. Use of today’s advance 3-Dimensional CAD systems coupled with the high accuracy of CNC machines enables the success of the determinate assembly approach for aircraft tooling. This approach provides the aircraft manufacturer significant lead-time reductions while at the same time it supports enhanced system flexibility. Determinate assembly for aircraft tooling has been proven to be high successful for tooling manufacture on large-scale system such as the A380 and A340–600 wing assembly projects.

British Aerospace, Airbus Ltd., Chester, UK manufactures the main wing box assembly for all current Airbus programs. Titanium interference fasteners are used in large numbers throughout these aircraft structures. On the lower wing skin of the A320 alone there are approximately 11,000 of this fastener type. Currently, the majority of these fasteners are manually installed using pneumatic or hydraulic tooling. British Aerospace engineers recognized the significant potential which automation offers to reduce these current labor intensive installation methods. Electroimpact proposed extending Low Voltage Electromagnetic Riveter (LVER) technology to the automatic installation of these interference fasteners as well as rivets. Close liaison between Airbus and Electroimpact engineers resulted in the development of an automated LVER based lockbolt installation system, which is currently undergoing evaluation.