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In Aeronautic industry, when we launch a new industrialization for an aircraft sub assembly we always have the same questions in mind for drilling operations, especially when focusing on lean manufacturing. How can we avoid dismantling and deburring parts after drilling operation? Can a drilling centre perform all the tasks needed to deliver a hole ready to install final fastener? How can we decrease down-time of the drilling centre? Can a drilling centre be integrated in a pulse assembly line? How can we improve environmental efficiency of a drilling centre? It is based on these main drivers that AIRBUS has developed, with SPIE and SOS, a new generation of drilling centre dedicated for hard materials such as titanium, and high thicknesses. The first application was for the assembly of the primary structure of A350 engine pylons. The main solution that was implemented meeting several objectives was the development of orbital drilling technology in hard metal stacks.

The paper presents an innovative approach for the functional specification of complex and highly integrated aircraft control systems, such as the Environmental Control System (ECS), by applying model based specification methods. Complexity and effectiveness of modern ECS have significantly increased during the last few years along with development of new technologies and innovations in control engineering as well as digital data distribution and processing. Efficient management of cabin air flows on the one hand makes the ECS more energy-saving and on the other hand more complex with regard to its functionality and interaction with other interfaced aircraft systems. Numerous data interfaces to other systems and a high degree of automation are typical for a modern ECS. The aircraft manufacturer specifies the entire ECS functions and its interactions within the aircraft.

Currently the wing box rib assembly process requires the manual location and temporary fixing of components within product specific jig or fixtures for drilling. After drilling and reaming, parts are separated, cleaned, deburred prior to adding sealant, reclaiming and final bolting, but this may significantly increase cost, manufacturing lead-time, reduces flexibility and cannot usually be economically modified for use on other aircraft types. Due to potential increase in demand for the next generation single isle aircraft, existing tooling solutions have to be improved and new technologies have to be developed. This paper describes the development and testing of flexible tooling to provide clamping and support for drilling wing box ribs to mating rib posts within a restricted environment. Results are presented along with a discussion of the problems that may be encountered during clamping trials.

There is an ever growing demand for blind fastener in the aerospace industry. This demand is driven not only by the advantages of single sided installation, but also by the potential to fully automate their installation process. Blind fasteners can easily be integrated with innovative end-effectors that combine drilling, installation and inspection systems, enabling the reduction of process cycle times and their associated cost savings. Clearly the advantages of single sided installation are a key benefit, but it cannot be forgotten that currently the mechanical performance of these systems is reduced compared with conventional threaded or swaged parallel shank fasteners. There are other important drawbacks existing around them which could penalise significantly the optimised design and performance of the structures. Specific key characteristics that take into account some of these drawbacks have been established by Airbus which will be referenced in this paper.

Industrial requirements imply optimizing the development cycle, reducing manufacturing costs and reaching marketable product maturity as fast as possible. The design stage often involves multiple sites and various partners. In this context, the use of computer simulation becomes absolutely necessary to meet industrial needs. Nevertheless, this activity can be effective only if it is integrated correctly in the industrial organization. In the aeronautical and space systems industry, mechanical specifications often require the use of composites reinforced by continuous carbon fibers. The goal of this article is to describe how, on a time frame of nearly twenty years, a series of scientific and technical tasks were carried out in partnership in order to develop, validate and implement Resin Transfer Molding (RTM) flow simulation and cure analysis for high performance composites. The research stage started at the university in 1991.

The paper describes the methodology of contact problem solving that is used in specialized software code aimed at simulation of aircraft assembly process. For considered class of problems it is possible to radically reduce the number of unknowns without loss of accuracy. The results of validation of developed code against physical experiments and commercial FEM codes are also given.

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.

The paper is devoted to the simulation of A320 wing assembly on the base of numerical experiments carried out with the help of ASRP software. The main goal is to find fasteners’ configuration with minimal number of fastening elements that provides closing of admissible initial gaps. However, for considered junction type initial gap field is not known a priori though it should be provided as input data for computations. In order to resolve this problem the methodology of random initial gap generation based on available results of gap measurements is developed along with algorithms for optimization of fasteners' configuration on generated initial gaps. Presented paper illustrates how this methodology allows optimizing assembly process for A320 wing.

Over the last few years, IT systems have quickly found their way onboard aircrafts, driven by the continuous pursuit of improved safety and efficiency in aircraft operation, but also in an attempt to provide the ultimate in-flight experience for passengers. Along with IT systems and communication links came IT security as a new factor in the equation when evaluating and monitoring the operational risk that needs to be managed during the operation of the aircraft. This is mainly due to the fact that security deficiencies can cause services to be unavailable, or even worse, to be exploited by intentional attacks or inadvertent actions. Aircraft manufacturers needed to develop new processes and had to get organized accordingly in order to efficiently and effectively address these new risks.

Pulsed assembly lines are providing an enormous potential to the aviation industry, especially in terms of reduced lead times, optimized asset utilization and an increased ratio of value adding processes. As it comes near to flow manufacturing the realization of a pulsed assembly line leads to special requirements to the use of NC programs for automated drilling and fastening processes, especially as a result of the unique part positions upon each pulse and concerning the balancing of the work onto several serialized fastening machines. The key to those challenges are versatile NC part programs that eliminate the need for any additionally written NC programs by self-adapting onto the concrete situation within the working areas of the production line.

In Aeronautic industry, when we launch a new industrialization for an aircraft sub assembly we always have the same questions in mind for drilling operations, especially when focusing on lean manufacturing. How can we avoid dismantling and deburring parts after drilling operation? Can a drilling centre perform all the tasks needed to deliver a hole ready to install final fastener? How can we simplify specific jigs used to maintain parts during drilling operations? How can we decrease down-time of the drilling centre? Can a drilling centre be integrated in a pulse assembly line? How can we improve environmental efficiency of a drilling centre? It is based on these main drivers that AIRBUS has developed, with SPIE and SOS, a new generation of drilling centre dedicated for hard materials such as titanium, and high thicknesses. The first application was for the assembly of the primary structure of A350 engine pylons.

Due to the importance of fulfilling the actual and upcoming environmental legislation, it is an Airbus main target to develop eco-efficient materials. Under consideration of the economical effects, these processes will be implemented into the production line. This paper gives an overview of Airbus and its partners research work, the results obtained within the frame of the European funded, integrated technology demonstrator (ITD) ECO Design for Airframe. This ITD is part of the joint technology initiative Clean Sky. Developments with different grade of maturity from “upstream” as the investigation of materials from renewable recourses up to materials now in use in production as low volatile organic compounds cleaner are under investigation. As a basis for future eco-efficient developments an approach for a quantitative life cycle assessment will be demonstrated.

Automation in aerospace industry is often in the form of dedicated solutions and focused on processes like drilling, riveting etc. The common industrial robot has due to limitations in positional accuracy and stiffness often been unsuitable for aerospace manufacturing. One major cost driver in aircraft manufacturing is manual assembly and the bespoke tooling needed. Assembly tasks frequently involve setting relations between parts rather than a global need for accuracy. This makes assembly a suitable process for the use of force control. With force control a robot equipped with needed software and hardware, searches for desired force rather than for a position. To test the usefulness of force control for aircraft assembly an experimental case aligning a compliant rib to multiple surfaces was designed and executed. The system used consisted of a standard ABB robot and an open controller and the assembly sequence was made up of several steps in order to achieve final position.

The aerospace manufacturing sector is continuously seeking automation due to increased demand for the next generation single-isle aircraft. In order to reduce weight and fuel consumption aircraft manufacturers have increasingly started to use more composites as part of the structure. The manufacture and assembly of composites poses different constraints and challenges compared to the more traditional aircraft build consisting of metal components. In order to overcome these problems and to achieve the desired production rate existing manufacturing technologies have to be improved. New technologies and build concepts have to be developed in order to achieve the rate and ramp up of production and cost saving. This paper investigates how to achieve the rib hole key characteristic (KC) in a composite wing box assembly process. When the rib hole KC is out of tolerances, possibly, the KC can be achieved by imposing it by means of adjustable tooling and fixturing elements.

Four years ago Airbus became actively involved in the SAE E36, Electronic Engine Control committee. This paper presents an Airframe Manufacturer view of one current working practices discussion relative to the FADEC electrical hardware change and describes an Airframe Manufacturer views on the committee's effectiveness along with a vision for its future. The SAE E36 committee is a representation of the propulsion control engineering community. The members comes from Airworthiness Authorities and other government and military agencies, airframers, engine manufacturers and control suppliers from North America, South America and Europe (including Russia). An active involvement allows an aircraft manufacturer to participate actively in the process and “to set the standard”. An additional benefit is to be aware of “what's hot”.

Model Based Safety techniques have been developed for a number of years, though the models have not been customised to help address the safety considerations/ actions at each refinement level. The work performed in the MISSA Project looked at defining the content of “safety models” for each of the refinement levels. A modelling approach has been defined that provides support for the initial functional hazard analysis, then for the systems architectural definition level and finally for the systems implementation level. The Aircraft functional model is used to apportion qualitative and quantitative requirements, the systems architectural level is used to perform a preliminary systems safety analysis to demonstrate that a system architecture can satisfy qualitative and quantitative requirements.

During mechanical assembly, individual parts are joined by different types of fasteners which are commonly to be installed into tightly tolerated holes. Drilling of widely used modern materials like CFRP and titanium leads to challenges in terms of tool and process development. A significant challenge is one step drilling in assemblies made from mixed material stacks. It results in deviating hole diameters making the additional reaming operation essential.”But also drilling of thick single material stacks imposes difficulties in terms of hole tolerance, chip extraction, heat accumulation and lubrication issues, leading to the necessity of drilling in several steps to achieve the required hole quality and integrity. During orbital drilling the drive spindle rotates eccentrically in addition to tool rotation and feed movement, leading to a circular path of the cutting tool. Orbital drilling can offer advantages compared with conventional drilling and reaming.

Gaps between structural components have been a common problem since the start of aviation. This has usually been caused by the manufacturing tolerances of the components in question not being sufficiently tight. An example where such issues arise is in the assembly of a wing skin to rib feet to form an aircraft wing-box, where it is commonly found that, whilst some rib feet are in contact with the wing skin, others are spaced from it. Yet a strong connection between the wing skin and the rib feet is important to maintain the structural strength of the wing-box. To eliminate the existing gaps, the current approach, used in many manufacturing production lines, involves filling in the gaps to the required shape by applying liquid or solid shim to the rib feet. This is a relatively long and expensive process. To overcome these current inherent difficulties in interface management, a method to eliminate the shimming requirement between component interfaces is presented.

Significant effort has been applied to the introduction of automation for the structural assembly of aircraft. However, the equipping of the aircraft with internal services such as hydraulics, fuel, bleed-air and electrics and the attachment of movables such as ailerons and flaps remains almost exclusively manual and little research has been directed towards it. The problem is that the process requires lengthy assembly methods and there are many complex tasks which require high levels of dexterity and judgement from human operators. The parts used are prone to tolerance stack-ups, the tolerance for mating parts is extremely tight (sub-millimetre) and access is very poor. All of these make the application of conventional automation almost impossible. A possible solution is flexible metrology assisted collaborative assembly. This aims to optimise the assembly processes by using a robot to position the parts whilst an operator performs the fixing process.

This paper presents the development of a high density packaging technology for wide band gap power devices, such as silicon carbide (SiC). These devices are interesting candidates for the next aircraft power electronic converters. Effectively they achieve high switching frequencies thanks to the low losses level. High switching frequencies lead to reduce the passive components size and to an overall weight reduction of power converters. Moreover, SiC devices may enable operation at junction temperatures around 250°C. The cooling requirement is much less stringent than for usual Si devices. This might considerably simplify the cooling system, and reduce the overall weight. To achieve the integration requirements for SiC devices, classical wire bonding interconnection is replaced by a stacked packaging using bump interconnection technologies, called sandwich. These technologies offer two thermal paths to drain heat out and present more power integration possibilities.