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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.

Airbus is a leading aircraft manufacturer with the position as technology driver and a distinct customer orientation, broad commercial know-how and high production efficiencies. It is constantly working on further and new development of its products from ecological and economical points of view. Fuel Cell Systems (FCS) on board of an aircraft provide a good opportunity to address both aspects. Based on existing and upcoming research results it is necessary to find trend-setting measures for the industrial implementation and application of this technology. Past and current research efforts have shown good prospects for the industrial implementation and application of the fuel cell technology. Being an efficient source of primarily electric power the fuel cell would be most beneficial when used in conjunction with electrical systems.

Airbus business and Extended Enterprise require more and more involvement of design and built suppliers, tier 1 but also across the complete supply chain i.e. tier 2-n. These suppliers are not working only for Aerospace industry and may have different cultures. The pressure on cost and overall efficiency is high and everybody has to cope with obsolescence and new regulation (e.g. REACH (Registration, Evaluation and Authorization and Restriction of Chemicals)). So it became very important for Airbus to clarify the criteria under which a change can be done without Airbus review, and criteria under which a change can be done without Airworthiness authority review.

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 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.

In the framework of the European ICE GENESIS project (https://www.ice-genesis.eu/), a field experiment was conducted in the Swiss Jura in January 2021 in order to characterize snow microphysical properties and document snow conditions for aviation industry purposes. Complementary to companion papers reporting on snow properties, this study presents an investigation on mixed-phase conditions sampled during the ICE GENESIS field campaign. Using in situ measurement of the liquid and total water content, the ice mass fraction is calculated and serves as a criteria to identify mixed-phase conditions. In the end, mixed phase conditions were identified in almost 30 % of the 3800 km long cloud samples included in the ICE GENESIS dataset. The data suggests that the occurrence of mixed-phase does not clearly depend on temperature in the 0 to -10 °C range, but varies significantly from one cloud system to another.

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.

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.

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.

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.

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.

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”.

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.

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.

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.

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.

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.

Fuel on-board dehydration during flight technologies has been modeled and experimentally studied on a laboratory testing setup in normal specific gas flow rates range of 0.0002-0.0010 sec-₁. Natural air evolution, ullage blowing and fuel sparging with dry inert gas have been studied. It has been shown that natural air evolution during aircraft climb provides a significant, substantial, but insufficient dehydration of fuel up to 20% relative. Ullage blowing during cruise leads to a constant, but a slow dehydration of fuel with sufficient column height concentration gradient. Dry inert gas sparging held after the end of the natural air evolution or simultaneously with natural air evolution provides rapid fuel dehydration to the maximum possible values. It potentially may eliminate water release and deposition in fuel to -50°C. It has been found that for proper dehydration, necessary and sufficient volume of dry inert gas to volume of fuel ratio is about 1.

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.

Safety is one of the most important aspects of which we are concerned with in the field of aerospace-systems development. There are a variety of safety assessment activities that are performed throughout a system's lifecycle. Multiple interrelated safety analysis artifacts are generated from the process. However, requirements and guidance for the synthesis and validation of the results of this analysis are insufficient and are not explicit. In traditional system development processes, certification coordination, safety assessment, requirements validation, and implementation verification are generally treated as supporting processes, which are concurrent and interactively dependent throughout the iterative development of a system. In SAE ARP4754A, these processes are stressed as integral processes with traceability between safety requirements and the dependencies between safety assessment activities highlighted as an important concern.