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The work describes a concept application to aid a safety engineer to perform an audit of a production aircraft against safety driven installation requirements. The capability is achieved using the following steps: A) Image capture of a product and measurement of distances between datum points within the product with/without references to a planar surface B) A digital reconstruction of the fabricated product by using multiple captured images to reposition parts according to the actual model. C) The projection onto the 3D digital reconstruction of the safety related installation constraints, respecting the original intent of the constraints that are defined in the digital mock-up.

The intent of this paper is to provide a general overview of the main engineering and test activities conducted in order to support A350XWB Ice and Rain Protection Systems certification. Several means of compliance have been used to demonstrate compliance with applicable Certification Basis (CS 25 at Amendment 8 + CS 25.795 at Amendment 9, FAR 25 up to Amendment 129) and Environmental protection requirements. The EASA Type Certificate for the A350XWB was received the 30th September 2014 after 7 years of development and verification that the design performs as required, with five A350XWB test aircraft accumulating more than 2600 flight test hours and over 600 flights. The flight tests were performed in dry air and measured natural icing conditions to demonstrate the performance of all ice and rain protection systems and to support the compliance demonstration with CS 25.1419 and CS25.21g.

Most of the decisions taken every day are based on the results of measurements of all different events that occur around us. The reliability of these measurements depends basically on the environment in which they are carried out, the procedure defined and the equipment used, evaluating their different contributions through the uncertainty of measurement. In the case of the measuring equipment, the calibration process associated with adequate traceability provides part of the information necessary to contribute positively to the generation of reliability. However, the physical nature of the instruments means that all of them have a certain degree of drift in their metrological characteristics, which requires users to establish time intervals to confirm the maintenance of the goodness of measurement of such equipment.

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.

The new edition of the well known Care and Repair of Advanced Composites, 3rd Edition, improves on the usefulness of this practical guide geared towards the aerospace industry. Keith B. Armstrong, the original lead author of the first edition was still in charge of this project, counting on the expert support of Eric Chesmar, senior composites specialist at United Airlines. Mr. Chesmar is also an active member of SAE International's CACRC (Commercial Aircraft Composite Repair Committee), an elite group of industry experts dedicated to the standardization, safety, security, and efficiency of composite repairs in the airline industry. Mr. Francois Museux (Airbus) and Mr. William F. Cole II also contributed. Care and Repair of Advanced Composites, 3rd Edition, presents a fully updated approach to the training syllabus recommended for repair design engineers and composite repair mechanics.

This second edition has been extensively updated to keep pace with the growing use of composite materials in commercial aviation. A worldwide reference for repair technicians and design engineers, the book is an outgrowth of the course syllabus that was developed by the Training Task Group of SAE's Commercial Aircraft Composite Repair Committee (CACRC) and published as SAE AIR 4938, Composite and Bonded Structure Technician Specialist Training Document. Topics new to this edition include: Nondestructive Inspection (NDI) Methods Fasteners for Composite Materials A Method for the Surface Preparation of Metals Prior to Adhesive Bonding Repair Design Although this book has been written primarily for use in aircraft repair other applications including marine and automotive are also covered.

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.

Traditional solutions developed for the aerospace industry must overcome challenges posed for automation systems like design, requalification, large manual content, restricted access, and tight tolerances. At the same time, automated systems should avoid the use of dedicated equipment so they can be shared between jigs; moved between floor levels and access either side of the workpiece. This article describes the development of a robotic system for drilling and inspection for small aerostructure manufacturing specifically designed to tackle these requirements. The system comprises three work packages: connection within the digital thread (from concept through to operational metrics including Statistical Process Control), innovative lightweight / low energy drill, and auto tool-change with in-process metrology. The validation tests demonstrating Technology Readiness Level 6 are presented and results are shown and discussed.

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.

A test has been performed using a scaled aircraft wing section in an icing tunnel facility. The model had an electro-thermal ice protection system installed. The tests performed considered both anti-icing and de-icing modes of operation. The results have been assessed using numerical codes and the effect of model scaling has been considered. The non-scaled skin thickness of the model was found to modify the predicted behaviour of a full-scale installation, predominantly due to lateral conduction effects. The extent of this has been assessed and recommendations are made as to the performance that may be expected at full-scale.

Composite materials are increasingly being used in the manufacturing of structural components in aeronautics industry. A consequent light-weight design of CFRP primary structures requires adhesive bonding as the optimum joining technique but is limited due to a lack of adequate quality assurance procedures. The successful implementation of a reliable quality assurance concept for adhesive bonding within manufacturing and in-service environments will provide the basis for increased use of lightweight composite materials for highly integrated aircraft structures thus minimizing rivet-based assembly. The expected weight saving for the fuselage airframe is remarkable and therefore the driver for research and development of key-enabling technologies. The performance of adhesive bonds mainly depends on the physico-chemical properties of adherend surfaces.

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.

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.

Modern aircraft, such as A380 or A350 for Airbus, are very well connected in flight to ground stations through wireless communications. For maintenance and operations purpose, the aircraft is programmed to send regularly information such as flight reports based on the BITE messages (Built-In Test Equipment) or standard reports based on the value of physical parameters. Moreover, Airbus is capable of sending requests (called uplinks) to the aircraft to retrieve the value of different parameters in almost real-time. This ability, associated with adequate process, improves significantly the reaction time of the diagnostic and prognostic solutions that Airbus can provide to its customers. Traditionally Health Monitoring is considered useful when the Potential to Functional failure (P-F) interval is greater than one flight cycle.

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.

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.

In 1994, an ATR-72 crashed at Roselawn, Indiana, USA. It has been speculated that accident was due to Supercooled Large Droplet (SLD) icing. This accident led to a modification of the regulation rules with the definition of the Appendix O which includes freezing drizzle and freezing rain icing conditions. The associated NPRM (Notice of Proposed Rule Making) has been distributed to industry for comments on 29th June 2010 and could be applicable by beginning 2012. In order to comply with this new rule, the simulation tools, as Acceptable Means of Compliance, have to be improved and validated for these conditions. The paper presents the work performed within Airbus to review, improve and assess simulation tools capability to accurately predict physical phenomena related to SLD. It focuses in particular on splashing and bouncing phenomena which have been highlighted as the first order effects.

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 paper presents the numerical approach to simulation and optimization of A350 S19 splice assembly process. The main goal is to reduce the number of installed temporary fasteners while preventing the gap between parts from opening during drilling stage. The numerical approach includes computation of residual gaps between parts, optimization of fastener pattern and validation of obtained solution on input data generated on the base of available measurements. The problem is solved with ASRP (Assembly Simulation of Riveting Process) software. The described methodology is applied to the optimization of the robotized assembly process for A350 S19 section.

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.