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The presented paper describes the software complex developed in St. Petersburg Polytechnical University for AIRBUS aimed at simulation of aircraft assembly process. Previous version of this complex was described in [1].

The state-of-practice for aircraft manufacturers to diagnose guidance & control faults and obtain full flight envelope protection at all times is to provide high levels of dissimilar hardware redundancy. This ensures sufficient available control action and allows performing coherency tests, cross and consistency checks, voting mechanisms and built-in test techniques of varying sophistication. This hardware-redundancy based fault detection and diagnosis (FDD) approach is nowadays the standard industrial practice and fits also into current aircraft certification processes while ensuring the highest level of safety standards. In the context of future “sustainable” aircraft (More Affordable, Smarter, Cleaner and Quieter), the Electrical Flight Control System (EFCS) design objectives, originating from structural loads design constraints, are becoming more and more stringent.

In the framework of the aircraft global optimization, for future and upcoming programs, current research interests include more Electrical Flight Control System (EFCS) autonomy for a more easy-to-handle aircraft. A possible solution is to increase the number of redundant flight parameter sensors but to the detriment of the aircraft weight and so to the cost and performances. This paper proposes an algorithm using PLS (Partial Least Squares) to estimate a flight parameter from independent sensor measurements. The estimates are then used as so-called “software” or “virtual” sensors, allowing aircraft weight saving. This algorithm is based on an iterative processing and thus can be used in real time in the embedded flight control computer. Furthermore, the resulting flight parameter estimates can be used to detect failures. Different detection strategies are proposed and results show that this method can lead to robust detections.

In the past decades hydraulic systems have dominated actuation tasks in aerospace applications. Even today hydraulic actuation remains in first line for primary flight controls as well as for heavy consumers such as landing gear or auxiliary applications in the perimeter of military functions. Also in future, hydraulic systems and its consumers are candidates to fulfil operational and functional requirements and provide respective improvements to ensure product competitiveness. Thus, this paper deals with potential improvements on hydraulic system level such as, fluid monitoring and light weight applications linked to impacts on aircraft level or interfacing systems.

Traditionally, software in avionics has been totally separated from open-world software, in order to avoid any interaction that could corrupt critical on-board systems. However, new aircraft generations need more interaction with off-board systems to offer extended services, which makes these information flows potentially dangerous. In a previous work, we have proposed the use of virtualization to ensure dependability of critical applications despite bidirectional communication between critical on-board systems and untrusted off-board systems. We have developed a test bed to assess the performance impact induced by the use of virtualization. In this work, various configurations have been experimented that range from a basic machine without an OS up to the complete architecture featuring a hypervisor and an OS running in a virtual machine. Several tests (computation, memory, network) are carried out, and timing measures are collected on different hypervisors.

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.

Measurements in snow conditions performed in the past were rarely initiated and best suited for pure and extremely detailed quantification of microphysical properties of a series of microphysical parameters, needed for accretion modelling. Within the European ICE GENESIS project, a considerable effort of natural snow measurements has been made during winter 2020/21. Instrumental means, both in-situ and remote sensing were deployed on the ATR-42 aircraft, as well as on the ground (ground station at ‘Les Eplatures’ airport in the Swiss Jura Mountains with ATR-42 overflights). Snow clouds and precipitation in the atmospheric column were sampled with the aircraft, whereas ground based and airborne radar systems allowed extending the observations of snow properties beyond the flight level chosen for the in situ measurements.

The objective of this paper is to present a numerical method to rank thick ice shapes for aircraft by comparing the ice accretion effects for different icing scenarios in order to determine the more critical ice shape. This ranking allows limiting the demonstration of the aerodynamic characteristics of the aircraft in iced condition during certification to a reduced number of ice shapes. The usage of this numerical method gives more flexibility to the determination of the critical ice shapes, as it is not dependent of the availability of physical test vehicles and/or facilities. The simulation strategy is built on the Lattice Boltzmann Method (LBM) and is validated based on a representative test case, both in terms of aircraft geometry and ice shapes. Validation against existing experimental results shows the method exhibits an adequate level of reliability for the ranking of thick ice shapes.

The PLANET System was used for real-time satellite data transmission during the HAIC-HIWC Darwin field campaign (January to March 2014). The basic system was initially providing aircraft tracking, chat, weather text messages (METAR, TAF, etc.), and aeronautical information (NOTAMs) in a standalone application. In the framework of the HAIC project, many improvements were made in order to fulfill requirements of the onboard and ground science teams for the field campaign. The aim of this paper is to present the main improvements of the system that were implemented for the Darwin field campaign. New features of the system are related to the hardware component, the communication protocol, weather and tracking display, geomarkers on the map, and image processing and compression before onboard transfer.

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.

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.

Despite past research programs focusing on tropical convection, the explicit studies of high ice water content (IWC) regions in Mesoscale Convective Systems (MCS) are rare, although high IWC conditions are potentially encountered by commercial aircraft during multiple in-service engine powerloss and airdata probe events. To gather quantitative data in high IWC regions, a multi-year international HAIC/HIWC (High Altitude Ice Crystals / High Ice Water Content) field project has been designed including a first field campaign conducted out of Darwin (Australia) in 2014. The airborne instrumentation included a new reference bulk water content measurement probe and optical array probes (OAP) recording 2D images of encountered ice crystals. The study herein focuses on ice crystal size properties in high IWC regions, analyzing in detail the 2D image data from the particle measuring probes.

Increased production rates and cost reduction are affecting manufacturing in all mobility industry sectors. One enabling methodology that could achieve these goals in the burgeoning “Industry 4.0” environment is the optimized deterministic assembly (DA) approach. It always forms the same final structure and has a strong link to design-for-assembly and design-for-automation. The entire supply chain is considered, with drastic savings at the final assembly line level through recurring costs and lead-time reduction. Unsettled Technology Areas in Deterministic Assembly Approaches for Industry 4.0 examines the evolution of previous assembly principles that lead up to and enable the DA approach, related simulation methodologies, and undefined and unsolved links between these domains. Click here to access the full SAE EDGETM Research Report portfolio.

In its entirety, automation is part of an integrated, multi-disciplinary product development process including the design, process, production, logistics, and systems approach—it depends on all these areas, but it also influences them as well. Automation in aerospace manufacturing is present throughout the entire supply chain, from elementary part manufacturing at suppliers up to final assembly, and a clear understanding of all the benefits (and drawbacks) of automation would help designers and engineers select the right designs for and levels of automation. The Right Level of Automation Within Industry 4.0 examines all impacts of automation that should be known by designers, manufacturers, and companies before investments in automation-related decisions are made—regardless of the which industry they work in. The process and the set of criteria discussed in this report will help decision makers select the right level of automation.

In response to the ice crystal icing hazard identified twenty years ago, aviation industry, regulation authorities, and research centers joined forces into the HAIC-HIWC international collaboration launched in 2012. Two flight campaigns were conducted in the high ice water content areas of tropical mesoscale convective systems in order to characterize this environment conducive to ice crystal icing. Statistics on cloud microphysical properties, such as Ice Water Content (IWC) or Mass Median Diameter (MMD), derived from the dataset of in situ measurements are now being used to support icing certification rulemaking and anti-icing systems design (engine and air data probe) activities. This technical paper focuses on methodological aspects of the derivation of MMD. MMD are estimated from PSD and IWC using a multistep process in which the mass retrieval method is a critical step.

ARP4754A/ED-79A guidelines addresse the development cycle for aircraft and systems that implement aircraft functions. The current trend in system design is an increasing level of integration between aircraft functions and the systems that implement them. While there can be considerable value gained when integrating systems with other systems, the increased complexity yields increased possibilities for errors, particularly with functions that are performed jointly across multiple systems. Following the Aviation Rulemaking Advisory Committee (ARAC) recommendations to respond to this increased integration which referenced ARP4754/ED-79 in advisory materials for compliance to 14CFR/CS 25.1309 (see AMC 25.1309, published in 2002 and AC25.1309-Arsenal draft) the use of ARP4754A/ED79A in aircraft certification has become increasingly widespread.

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.

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.

AmSafe®, Airbus and IABG were the first in decades to undertake an ultimate forward load Full-Scale Test (FST) of a 9 g₁ Barrier Net. Barrier Nets are safety-critical products used during an emergency landing (FAR25.561/CS25.561) to protect passengers and crew. When Airbus Military required an A400M Barrier Net they identified requirements well beyond the "normal" and demanded that payloads from a rigid structure to a frangible be restrained. AmSafe uses non-liner Finite Element Analysis (FEA) technology to analyze their nets and proposed an innovative solution for a new Barrier Net to satisfy these very demanding requirements. Given these new requirements, it was decided to also carry out a Full-Scale Test (FST). This test required the expertise of IABG, a testing facility based in Germany.