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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 aviation sector has played a significant role in shaping the world into what it is today. The rapid growth of global economies and the corresponding sharp rise in the number of people now wanting to travel on business and for pleasure, has largely been responsible for the development of this industry. With a predicted rise in Revenue Passenger Kilometers (RPK) by over 150% in the next 20 years, the industry will correspondingly be a significant contributor to environmental emissions. Under such circumstances optimizing aircraft trajectories for lowered emissions will play a critical role amongst various other measures, in mitigating the probable environmental effects of increased air traffic. Aircraft trajectory optimization using evolutionary algorithms is a novel field and preliminary studies have indicated that a reduction in emissions is possible when set as objectives.

The main study illustrated in this paper deals with the computation of commands which allow an aircraft to recover a nominal energy trajectory from a low/high energy state during the approach phase. The commands taken into account in this paper are the slat/flap aerodynamic control surfaces which allow the aircraft to maintain the best lift performance for low velocities during the approach phase. In this study, it is supposed that the aircraft maintains a known vertical trajectory, simplified by a constant ground slope, while no engines and airbrakes are used. A non-linear optimization approach is studied in this paper and two methods are tested: a) Hermite-Simpson, trapezoidal collocation methods, b) Sequential numerical integration method. These different methods are tested and simulation results are given for comparison, with different initial velocities permitting to change the initial energy state.

The vision of SESAR is to integrate and implement new technologies to improve air traffic management (ATM) performance. Enhanced automation and new separation modes characterize the future concept of operations, where the role of the human operator will remain central by integrating more managing and decision-making functions. The expected changes represent challenges for the human actors in the aircraft and on ground and must be taken into account during the development phase. Integrating the human in the ATM system development starting from the early design phase is a key factor for future acceptability. This paper describes the adaptation of currently applied Cockpit Human Factors processes in order to be able to design the aircraft for the future ATM environment.

The Environmental Control System is a relevant element of any conventional or More Electric Aircraft (MEA). It is either the key consumer of pneumatic power or draws a substantial load from the electric power system. The objective of this paper is to present a tool for the design of Environmental Control Systems and to apply it to an unconventional system. The approach is based on a recently proposed methodology, which is improved with respect to flexibility and ease-of-use. Furthermore, modeling and simulation of vapor compression cycles is discussed, which are candidate technological solutions for More Electric Aircraft concepts. A steady-state moving boundary method is presented to model heat exchangers for such applications. Finally, the resulting design environment is applied to optimization of an unconventional ECS architecture and exemplary results are presented.

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.

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.

This paper describes the Airbus plans to use ADS-B in the future concept of operations in both the European SESAR and the US NEXTGEN concepts of operations. It details the different steps that are currently considered by Airbus roadmap to deploy ADS-B services and functions. In particular, the following points are described: Use of ADS-B OUT in Non Radar Airspace Use of ADS-B IN and the associated Airbus functions to offer a better Air Traffic Situation Awareness (ATSAW) package: the various applications for airborne, in trail climb/descent procedures or enhanced visual acquisition are particularly detailed. Use of ADS-B for the future Spacing function as currently considered in the initial ASAS implementation for SESAR: the three “Remain Behind”, “Merge at Waypoint then Remain behind” and the “Heading then merge behind” applications are explained.

Insufficient chip extraction often leads to disruptions of automated drilling processes and will have a negative impact on the surface qualities. One opportunity to avoid chip accumulation is based on a kinematically enforced chip breakage caused by sinusoidal axial oscillations of the drilling tool. Recent investigations have shown that the quality of chip extraction is, amongst others, considerably depending on the chip shape and mass which are defined by the cutting parameters feed, amplitude and frequency. So far only mechanical systems in the form of tool holders have been available on the market, which are restricted to a fixed frequency (oscillation frequency is coupled to the spindle speed). In the present study a spindle with magnetic bearings was used which allows to adjust the oscillation frequency independent of the spindle speed and therefore enables all opportunities to affect the generated chip shapes.

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.

Electroimpact has retrofitted two E4100 riveting gantry machines and two more are in process. These machines use the EMR (Electromagnetic Riveter) riveting process for the installation of slug rivets. We have improved the skin side EMR to provide fast and reliable results: reliability improved by eliminating a weekly shutdown of the machine. In paper 2015-01-2515 we showed the slug rivet injector using a Synchronized Parallel Gripper that provides good results over multiple rivet diameters. This injector is mounted to the skin side EMR so that the rivet injection can be done at any position of the shuttle table. The EMR is a challenging application for the fingers due to shock and vibration. In previous designs, fingers would occasionally be thrown out of the slots. To provide reliable results we redesigned the fingers retainer to capture the finger in a slotted plastic block which slides along the outside diameter of the driver bearing.

Increasing technical dependencies between the engineering disciplines driving the overall design of an aircraft and improving optimization techniques that make use of these interactions blur the lines between distinct disciplines and create demand for a harmonized flight physics model. In this paper we present considerations on a general framework that allows the representation of the equations and data from various domains in an object-oriented and scalable structure. Emphasis is put on the loads aspect with the distinct fields of gust loads, maneuver loads and ground loads analysis, which are essential for structural design. A fully generic, grid based data structure is presented, which is suitable for models of different granularity and applicability. All data is represented in this general form independent of its origin and may be transformed in between the different representations using splines. Coordinate transformations are handled automatically.

The introduction of Fly-By-Wire (FBW) and the increasing level of automation contribute to improve the safety of civil aircraft significantly. These technological steps permit the development of advanced capabilities for detecting, protecting and optimizing A/C guidance and control. Accordingly, this higher complexity requires extending the availability of aircraft states, some flight parameters becoming key parameters to ensure a good behaviour of the flight control systems. Consequently, the monitoring and consolidation of these signals appear as major issues to achieve the expected autonomy. Two different alternatives occur to get this result. The usual solution consists in introducing many functionally redundant elements (sensors) to enlarge the way the key parameters are measured. This solution corresponds to the classical hardware redundancy, but penalizes the overall system performance in terms of weight, power consumption, space requirements, and extra maintenance needs.

Within this paper, the AIRBUS approach on the development of rivetless nutplates as an alternative to riveted anchor nuts is described. Within the frame of a wider analysis, it was identified that currently used riveted anchor nut elements does have disadvantages with negative impact on an optimized cost-efficient and lead-time driven design and manufacturing environment. Rivetless nutplate systems provide some features that are potentially capable to mitigate some of the identified disadvantages of riveted elements. The paper covers the key requirements and objectives that were put in place in order to identify the most beneficial solution(s). It furthermore contains detailed information on the rivetless nutplate systems selected by AIRBUS and the justification for the selection that was made.

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.

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.

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.

This paper proposes a rearview on aeronautical innovation, addresses some 2000-2010 new products, and suggests elements of future vision, serving passengers aspirations. Over 100 years, aeronautics brilliantly domesticated flight: feasibility, safety, efficiency, international travel, traffic volume and noise, allowing airlines to run a business, really connecting real people. Despite some maturations, new developments should extend the notion of passenger service. So far, turbofans became silent and widebodies opened ‘air-bus’ travel for widespread business, tourism or education. Today airports symbolize cities and vitalize regional economies. 2000-2010 saw the full double-decker, the new eco-friendly freighter and electronic ticketing. In technology, new winglets and neo classical engines soon will save short-range blockfuel. In systems and maintenance, integrated modular avionics and onboard data systems give new flexibility, incl by data links to ground.

Glaciated icing conditions potentially leading to in-service event are often encountered in the vicinity of deep convective clouds. Nowcasting of these conditions with space-borne observations would be of a great help for improving flight safety and air-traffic management but still remains challenging. In the framework of the HAIC (High Altitude Ice Crystals) project, methods to detect and track regions of high ice water content from space-based geostationary and low orbit mission are investigated. A first HAIC/HIWC field campaign has been carried out in Australia in January-March 2014 to sample meteorological conditions potentially leading to glaciated icing conditions. During the campaign, several nowcasting tools were successfully operated such as the Rapid Development Thunderstorm (RDT) product that detects the convective areas from infrared geostationary imagery.