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McDonnell Douglas Aircraft in St. Louis, MO manufacturers various transport and fighter military aircraft such as the C-17 and the F/A-18. With shrinking military budgets and increased competition, market forces demand high quality parts at lower cost and shorter lead times. Currently, a large number of different fastener types which include both solid rivets and interference bolts are used to fasten these assemblies. The majority of these fasteners are installed by hand or by using manually operated C-Frame riveters. MDA engineers recognized that in order to reach their goals they would be required to rethink all phases of the assembly system, which includes fastener selection, part fixturing and fastener installation methods. Phase 1 of this program is to identify and to develop fastener installation processes which will provide the required flexibility. The EMR fastening process provides this flexibility.

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.

Northrop Corporation manufactures body panels for the Boeing 747 aircraft. There are 1259 different stringer configurations used on the three 747 models with an average of 839 stringers per ship set. Until recently, all drain holes and skin coordination pilot holes were drilled manually using plastic application template tools (PATTS). Inventory costs were high and manual drilling errors led to excessive scrap and rework rates. Northrop engineers recognized that automating the stringer drilling process would produce higher quality parts at a lower cost. Northrop worked with Electroimpact, Inc. to develop the Automatic Stringer Drilling System (ASDS). The ASDS automatically clamps and drills all straight and contoured stringers used on the 747. Stringers are mounted on a rotating platform that provides +/- 90° of motion. Two servo-servo drills are mounted on a cantilevered arm with 25 feet of X-axis travel.

The Handheld Low Voltage Electromagnetic Riveter(HHER) has been under development for the past three years. The HHER is an impulse device deriving its power from the discharge of a bank of capacitors through a pancake coil. This gives the HHER the advantage of an accurate and repeatable output force, which results in exceptional consistency in rivet upset dimensions. The rivet/hole interferences obtainable with the HHER have been shown in many cases to be superior to traditional rivet driving techniques, resulting in riveted joints that exhibit excellent fatigue life.(5) Typically, two opposing guns are used on either side of the rivet. These are synchronized through a control cable of arbitrary length. This feature allows accurate installation of slug rivets by hand, a function that in many cases is not possible with existing handheld tools.

The Boeing 787 Dreamliner will be the most fuel-efficient airliner in the world when it enters service in 2008. To help achieve this, Boeing will utilize state-of-the-art carbon fiber for primary structures. Advanced manufacturing techniques and processes will be used in the assembly of large composite structures. Electroimpact has proposed a system utilizing the low recoil Low Voltage Electromagnetic Riveter (LVER) to drill and install bolts. A test program was initiated between Boeing Materials Process and Engineering (MP&E) and Electroimpact to validate the LVER process for swaging titanium collars on titanium pins in composite material. This paper details the results of these tests.

Lightweight and flexible automated drilling machines are becoming more common in aerospace industry to address the increase in demand for low cost assembly solutions. Successful production implementation of the Flex Track system has been accomplished by matching applications with appropriate design features. Following the concept of small lightweight machines, which rely on local accuracy and sacrifice stiffness and shear mass, the Flex Track tackles problems on a detail level. This paper describes how the evolutionary progress of the Flex Track drilling system has and continues to address the increase in demand for low cost automated drilling systems.

Hand installation of 3/8", 5/16" and 1/4" diameter fatigue head style fasteners is required on some areas of 747 section 11 (center wing). The 3/8" diameter fasteners can require between 45-60 seconds to upset using conventional pneumatic riveting guns. As part of Boeing’s continuing effort to reduce cycle time and improve the factory working environment, a Boeing Quality Circle Team proposed using LVER technology as an alternative to conventional pneumatic percussion riveting hammers The hand operated HH500 system was developed in response to this request. The HH500 single shot upset reduces installation time as well as the noise levels and vibration experienced by the operators. The design of this system and the integration onto the factory floor are presented. The LVER forming rate is significantly higher than that of conventional pneumatic and hydraulic processes.

Boeing's wholly owned subsidiary in Australia, Hawker de Havilland produces all ailerons for the Boeing 737 family of aircraft. Increasing production rates required to meet market demand drove the requirements for a new updated approach to assembly of these parts. Using lean principals, a pulsed flow line approach was developed. A component of this new line is the integration of a flexible robotic drilling/trimming system. The new robotic system is required to meet aggressive tack time targets with high levels of reliability. The selected system was built on a Kuka KR360-2 conventional articulated arm robot. A significant challenge of this project was the requirement for the process head to work efficiently on an aileron in an existing jig. As a result a new side-mounted drill and trim end effector was developed. Automated tool changers for both cutters and pressure foot assemblies eliminated the requirement for in- process manual intervention.