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As a result of recommendation from the Augustine Panel, the direction for Human Space Flight has been altered from the original plan referred to as Constellation. NASA's Human Exploration Framework Team (HEFT) proposes the use of a Shuttle Derived Heavy Lift Launch Vehicle (SDLV) and an Orion derived spacecraft (salvaged from Constellation) to support a new flexible direction for space exploration. The SDLV must be developed within an environment of a constrained budget and a preferred fast development schedule. Thus, it has been proposed to utilize existing assets from the Shuttle Program to speed development at a lower cost. These existing assets should not only include structures such as external tanks or solid rockets, but also the Flight Software which has traditionally been a ?long pole? in new development efforts. The avionics and software for the Space Shuttle was primarily developed in the 70's and considered state of the art for that time.

The performance enhancement of a vertical tail provided by aerodynamic flow control could allow for the size of the tail to be reduced while maintaining similar control authority. Decreasing tail size would create a reduction in weight, drag, and fuel costs of the airplane. The application of synthetic jet actuators on improving the performance of the vertical tail was investigated by conducting experiments on 1/9th and 1/19th scale wind tunnel models (relative to a Boeing 767 tail) at Reynolds numbers of 700,000 and 350,000, respectively. Finite-span synthetic jets were placed slightly upstream of the rudder hinge-line in an attempt to reduce or even eliminate the flow separation that commences over the rudder when it was deflected to high angles. Global force measurements on the 1/9th scale model showed that the flow control is capable of increasing side force by a maximum of 0.11 (19%). The momentum coefficient that created this change was relatively small (Cμ = 0.124%).

Over 1,200 large diameter holes must be drilled into the side-of-body join on a Boeing commercial aircraft's fuselage. The material stack-ups are multiple layers of primarily titanium and CFRP. Due to assembly constraints, the holes must be drilled for one-up-assembly (no disassembly for deburr). In order to improve productivity, reduce manual drilling processes and improve first-time hole quality, Boeing set out to automate the drilling process in their Side-of-Body join cell. Implementing an automated solution into existing assembly lines was complicated by the location of the target area, which is over 15 feet (4 meters) above the factory floor. The Side-of-Body Drilling machines (Figure 1) are capable of locating, drilling, measuring and fastening holes with less than 14 seconds devoted to non-drilling operations. Drilling capabilities provided for holes up to ¾″ in diameter through stacks over 4.5″ thick in a titanium/CFRP environment.

Two Automated Electromagnetic Riveting Assembly Cells (AERAC) were manufactured for Textron Aerostructures by Electroimpact, Inc. The AERAC installs the final rivets in the A330/A340 upper wing panel in the floor assembly jig. At Textron for each wing the corresponding floor assembly jigs for each wing are lined up end to end. An operating procedure in which the formboards are removed in bays allows efficient operation of an in the jig riveter such as the AERAC. Specialized machine codes developed for the AERAC allows quick fully programmed stringer to stringer jumps of the stringer side offset tooling. The AERAC is programmed entirely from a CATIA drawing of the part. Of the 5 axes of rivet data available only two are retained for use by the AERAC.

Since the 1960's, lightning protection of aircraft has been an important design aspect, a concern for the flying public, aircraft manufacturers and the Federal Aviation Administration (FAA). With the implementation of major aircraft structures fabricated from carbon fiber reinforced plastic (CFRP) materials, lightning protection has become a more complicated issue to solve. One widely used material for lightning strike protection of CFRP structures within the aerospace industry is expanded metal foil (EMF). EMF is currently used in both military and commercial passenger aircraft. An issue that has historically been an area of concern with EMF is micro cracking of paint on the composite structure which can result in corrosion of the metal foil and subsequent loss of conductivity. This paper addresses the issues of stress and displacement in the composite structure layup which contribute to paint cracking caused by aircraft thermal cycling.

The 787 Section 11 Assembly Cell is a combination fixed post and moving frame holding and indexing system, designed to determinately build the 787 Section 11 Wing box. The retractable overhead frame allows maximum clearance for safer and faster loading and unloading of component parts, as well as completed wingbody sections. Additionally, each index is also retractable allowing maximum fastener access inside the jig.

A new Low-Voltage Electromagnetic Riveting (LVER) machine has entered service at the Airbus UK wing factory in Broughton, Wales, in an assembly workcell for A320 family wing panels. The machine is based on existing Electroimpact technology but incorporates numerous design modifications to process tools, fastener feed hardware, machine structure and the control system. In the first months of production these modifications have demonstrated clear improvements in fastener installation cycle times and machine reliability.

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.

Electroimpact, in cooperation with a large airframe manufacturer, has developed Automated Fiber Placement equipment capable of depositing material at speeds in excess of 2000 inches per minute. As the machine lays down each new ply of material, the area forward to machine motion is heated just in advance of pressing the tape against the substrate. A fast-reacting, high-power infrared emitter heats this area quickly and safely. The design of these heaters is the subject of this paper.

Automated Fiber Placement (AFP) equipment has been developed capable of laying fiber in excess of 2000 inches per minute on full-size, complex parts. Two such high-speed machines will be installed for production of a nose section for a large twin-aisle commercial aircraft fuselage at Spirit AeroSystems in Wichita, Kansas along with a rotator for the fuselage mandrel. The problem of cutting and adding on the fly at these speeds requires thorough re-evaluation of all aspects of the technology, including the mechanical, controls, servos systems, and programming systems. Factors to be considered for high speed cut and add on the fly are discussed.

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.

Electroimpact has developed a new Fastener Feed System which provides an automated solution for fasteners previously hand fed via drop tubes. The hardware is simple, compact, and is supplied a fraction of the cost of hoppers or cartridges. It can be used as a primary feed system or it can be used as an auxiliary feed system when combined with feed systems designed for high quantities of fasteners. We have installed this system on the A380 Stage 0 LVER lower panel wing machines and feed 5 diameters, 10 grips each, for a total of 50 different fastener types. This system moves 547 total fasteners per ship set from manual feed to automatic feed, saving considerable build time.

Through the use of an “Integrated Product Team” approach and new inspection techniques incorporating the latest in imaging capabilities and automation, the costs of some man-power intensive tasks can now be drastically reduced. Also, through the use of advanced eddy current techniques, the detectable size of cracks under flush-head fasteners can be reduced while maintaining reliable inspection. This article describes the evaluation and results obtained using eddy current technology to determine the minimum fasteners, Secondly, it describes the integrated efforts of engineers at Boeing DPD and Northwest Airlines in the successful application of MAUS eddy current scanning of the DC-10 circumferential and axial crow splices. The eddy current scanning greatly reduced the man-hour effort required for the existing radiographic inspection

Advancements in electrical, mechanical, and structural design onboard modern more electric aircraft have added significant stress to the thermal management systems (TMS). A thermal management system level analysis tool has been created in MATLAB/Simulink to facilitate rapid system analysis and optimization to meet the growing demands of modern aircraft. It is anticipated that the tracking of thermal energy through numerical integration will lead to more accurate predictions of worst case TMS sizing conditions. In addition, the non-proprietary nature of the tool affords users the ability to modify component models and integrate advanced conceptual designs that can be evaluated over multiple missions to determine the impact at a system level.

The new combinations such as composites and titanium that are being used on today's new airplanes are proving to be very challenging when drilling holes during manufacturing and assembly operations. Gone are the days of hand drilling with high speed steel drills through soft aluminum structure, after which aluminum rivets would be swaged into those holes with very generous tolerances. The drilling processes today need to use cutter materials hard enough and tough enough to cut through hard metals such as titanium, yet be sharp enough to resistant abrasion and maintain size when drilling through composites. There is a constant search for better cutters and drills that can drill a greater number of holes. The cost of materials used in today's aircraft is much higher. The cutting tools are more expensive and the hole tolerances are much tighter.

Wing skin riveting and bolting requires the surface to be flush to +/–.025mm(.001″) to produce an acceptable finish. Using the method described in this paper, automated wing riveting technology and panel assembly techniques can achieve better shave height and countersink accuracies than have previously been possible in production.

Electroimpact developed an end effector for Airbus UK, Ltd. for use on a Kuka KR350 robot provided by Airbus UK. The end effector is referred to as the DDEE (Drill and Drive End Effector), and incorporates four main functions. The end effector pushes up on a wing panel with programmable pressure, drills a hole with a servo-servo drill, inspects the hole with a servo ball-type hole gauge and then drives a pin-tail style lockbolt into the hole. The end effector is being used as part of a development and feasibility study for incorporating automation into the wing panel manufacture process.

Different options have been examined for providing minerals to plants for bioregeneration. The baseline option is to ship the minerals. The equivalent system mass of two different bioreactor systems for recycling a portion of these minerals, a fixed-film bioreactor and a stirred-tank reactor are calculated. Either option could reduce the ESM for providing these minerals for a 15-year mission to Mars, with 50% food closure.

In the wake of the 9/11/2001 hijacking events, the Federal Aviation Administration (FAA) has emphasized the need for enhanced flight deck doors on commercial airplanes. The paper describes enhanced flight deck door, which meets the new FAA requirements for intrusion resistance and ballistic protection. In addition, the new door meets the existing requirements for rapid decompression, flight crew security and rescue.

The use of paint automation in commercial aircraft production is being studied to reduce process cycle times, provide a higher quality paint finish, lower emissions, and increase process consistency. The cost of new aircraft paint hangars and increasing production rates is driving a need for increased capacity in existing facilities by using new coatings and technology. Testing of robotic painting at Boeing has uncovered unique differences between aerospace and automotive applications. Paint cure times, number of paint colors, environment control, and part size considerations are some of the issues that make aerospace application of coatings more difficult than automotive applications. Understanding the unique factors involved in the robotic application of commercial aerospace coatings is important for future advancements in application technology, gains in aircraft paint hangar capacity, delivering quality coating finishes, and lowering environmental footprint.