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The composites development team at Bombardier Aerospace has pushed the Integrated Product Development Team to a new level. The team has been created outside the business priorities and was partially funded by a provincial government initiative to create a greener aircraft. A dedicated R&D team can reduce the gap between the different disciplines by encouraging them to work as one entity and rapidly develop high Technology Readiness Level (TRL) and high Manufacturing Readiness Level (MRL) solutions. Additionally, the interactions between the groups create a harmonization of the development philosophy and a sharing of the building block approach. This leads to a significant cost and lead time reduction in the coupon, element and detail testing. The constitution of the team also has a great impact on the level of expertise and the flexibility to adjust to new demands.

Nowadays, optimization of manufacturing and assembly operations requires taking into account the inherent processes variations. Geometric and dimensional metrology of mechanical parts is very crucial for the aerospace industry and contributes greatly to its. In a free-state condition, non-rigid parts (or compliant parts) may have a significant different shape than their nominal geometry (CAD model) due to gravity loads and residual stress. Typically, the quality control of such parts requires a special approach where expensive and specialized fixtures are needed to constrain dedicated and follow the component during the inspection. Inspecting these parts without jig will have significant economic impacts for aerospace industries, reducing delays and the cost of product quality inspection. The Iterative Displacement Inspection (IDI) algorithm has been developed to deal with this problem.

Aerospace panels are commonly restrained on complex inspection fixture jigs during the measurement process. Forces used to restrain the part are also monitored because of the part functional requirements. Given the difficulties in measuring these types of parts, this paper reviews the available fixtureless inspection methods with a focus on the challenges of their implementation and their aptitude to be used to estimate the part profile and the necessary restraining forces of an aerospace panel. To perform this investigation, finite element analysis is used to predict the constrained shape of four (4) simulated free state aerospace panel, with two different type of boundary condition, in five scenarios. From those analyses, the importance and limits of current finite element boundary setting method embedded in fixtureless inspection methods for nonrigid parts are highlighted.

Aircraft systems are designed with reliability, safety and cost effectiveness in mind. The certification of the aircraft is based on tests and results of theoretical analyses that show the compliance with the FAR/JAR requirements. Monitoring for safety for in-service aircraft is an important, critical and extremely complex process. The ultimate objective is to assure that the safety level is equal to the original estimate or better. The manufacturer of the aircraft is particularly responsible for overall monitoring and assessment of all safety related events and corrective actions. Many different philosophies were adopted for this purpose. The safety monitoring and audit strategy is generally based on experience, engineering judgment, event analysis and numerical quantification by using probability theory and statistical tools. The aircraft sequential entry in the service and the aging of their components lead to the non-homogeneity of the fleet.

During its flight an aircraft can be struck by lightning and the induced high current will require a highly conductive airframe skin structure in order for it to propagate through with minimum damage. However an aircraft skin is generally coated with paint and the airframer does not always have control on the paint thickness. Paint thickness generates heightened concerns for lightning strike on aircraft, mainly because most of coatings dedicated to that purpose are non-conductive. Using insulating material or non-conductive coating with certain thickness may contribute to or increase damage inflicted by the swept stroke lightning energy, even on metallic structures Due to its high relative permittivity, a non-conductive paint or coating on a fuselage skin surface will contribute to slow down the lightning current propagation through structure. With this comes the risk of increasing heat that will favor structural damage and possible melt through.

This paper presents a generic Redundancy Management (RM) requirements definition process that is applicable to a complex system RM requirements development. In the aerospace industry, the ‘Aerospace Recommended Practices’ (ARP) 4754 and 4761 are typically used processes to ensure given safety and availability goals for complex systems. The process proposed in this paper is based on these standard guidelines and enhances them to provide a standardized process for the development of RM requirements with interactions between the system requirements development and the preliminary system safety assessment processes. The output of this process will help to achieve the following objectives: The system RM/failure monitoring requirements are defined commensurate with the system safety and availability requirements; the system is fault-tolerant to the degree necessary to meet the system safety and availability requirements; the system is robust and the system architecture is optimized.

During the development of an aircraft, a comprehensive understanding of the electrical load profile is essential to properly estimate the required electrical power to be generated and distributed by the electrical system, also known as EPGDS - Electrical Power Generation and Distribution System. By sizing the EPGDS early in the development process, system parameters like weight and volume can be estimated and applied to the multidisciplinary design optimization process, in search for optimized design solutions at the conceptual aircraft level when developing integrated aircraft systems. With this in mind, a methodology was developed to estimate the amount of electrical power required by the aircraft systems during a typical mission flight cycle.

This study investigates challenges associated with integrating a passenger (PAX) door on complex compound curvature (CCC) fuselages. Aerospace companies are investigating concepts that no-longer have constant cross-section (CS) fuselages. The PAX door is based on a generic semi-plug door for a long range business jet (BJ). This study investigates limitations of locating the door by varying the transition zone angle. A parametric CATIA tool, coupled with the use of finite element model (FEM) results can highlight key drivers in the design and location of PAX doors, creating a first-draft structural layout. The associated impact on the design and structural architecture for a fold down PAX door with integrated stairs is discussed. The impact of CCCs on the PAX door design is investigated with consideration to location, kinematics and function of the door.

Ice adhesion on critical aircraft surfaces is a serious potential hazard that runs the risk of causing accidents. For this reason aircraft are equipped with active ice protection systems (AIPS). AIPS increase fuel consumption and add complexity to the aircraft systems. Reducing energy consumption of the AIPS or replacing the AIPS by a Passive Ice Protection System (PIPS), could significantly reduce aircraft fuel consumption. New coatings with superhydrophobic properties have been developed to reduce water adherence to surfaces. Superhydrophobic coatings can also reduce ice adhesion on surfaces and are used as icephobic coatings. The question is whether superhydrophobic or icephobic coatings would be able to reduce the cost associated with AIPS.

Statistical process control (SPC) has been extensively used in many different industries including automotive, electronics, and aerospace, among others. SPC tools such as control charts, process capability analysis, sampling inspection, etc., have definitive and powerful impact on quality control and improvement for mass production and similar production systems. In aerospace manufacturing, however, applications of SPC tools are more challenging, especially when these tools are implemented in processes producing products of large sizes with slower production rates. For instance, following a widely accepted rule-of-thumb, about 100 units of products are required in the first phase of implementing a Shewhart type control chart. Once established, it then can be used for process control in the second phase for actual production process monitoring and control.

A particular field of aerospace engineering is dedicated to the study of aircraft that are so energetically efficient, that the power produced by a human being enables it to takeoff and maintain sustained flight without any external or stored energy. These aircraft are known as Human-Powered Aircraft (HPA). The objective of the present work is to design a single-seat HPA applying multidisciplinary optimization techniques with an objective function that minimizes both the power required and the stall speed, representing respectively, an easier and safer aircraft to fly. In the first stage, a parametric synthesis model is created to generate random aircraft and assess their aerodynamic(utilizing a 3D vortex lattice method code and a component drag buildup method for the drag polar), stability and control(utilizing static stability criteria), weight (estimated using historical data) and performance (using the thus calculated data) characteristics.

This paper presents work on the development of a low cost fuselage C-frame for aircraft primary structure using a Light Resin Transfer Molding (RTM) process. Compared to labor intensive hand layup prepreg technologies, Light RTM offers some substantial advantages by reducing infrastructure requirements such as hydraulic presses or autoclaves. Compared to Prepreg, Light RTM tooling creates two finished surfaces, which is an advantage during installation due to improved dimensional accuracy. The focus of this work was to develop means of achieving high fiber volume fraction structural frames using low cost tooling and a low volume manufacturing strategy. In this case a three piece Light RTM mold was developed using an internal mandrel. To achieve the strength requirements, a combination of crimped and non-crimped fabrics were selected for the reinforcing preform.

3D ice accretion codes have been available for a few decades but, depending on the specific application, their use may be cumbersome, time consuming and requiring a great deal of expertise in using the code. In particular, simulations of large 3D glaze ice accretions using multiple layers of ice is a very challenging and time consuming task. There are several reasons why 2D icing simulations tools are still widely used in the aircraft industry to produce realistic glaze ice shapes. 2D codes are very fast and robust, with a very short turn-around time. They produce adequate results in areas of the aircraft where 3D effects on airflow or droplets concentration can be neglected. Their use can be extended to other areas of the aircraft if relevant 3D effects can be taken into account. This paper proposes a simulation methodology that includes three levels of corrections to extend the use of 2D icing codes to most of the aircraft surfaces.

This paper discusses the correlation of IVHM (Integrated Vehicle Health Management) as an emerging aerospace discipline and the Big Data paradigm widely discussed in the Information Technology industry. The 4-V model is discussed to qualify a Big Data problem in terms of the volume, variety, velocity and veracity of the data involved. Big Data management allows, for example, correlations to be found to “spot business trends, determine quality of research, prevent diseases, combat crime, and determine real-time roadway traffic conditions”. Examining these two fields side by side is necessary and desirable because innovation is very likely to occur when and where different but correlated domains interface. This paper compares the most significant technical components required for Big Data Analytics and IVHM to work.

The safe operation of technical systems is a mandatory basic requirement for the entire industry. However, there are specific industries where the safety of operation is critical and is considered as a required characteristic. These types of industries include the aerospace, military, civil aviation, nuclear power, as well as chemical and automotive industries. Safety is everyone's responsibility but engineering plays the most important role in the course of achieving a safe product operation. There are two specific phases of the product life cycle where the safety characteristics should be addressed by engineering activities: the design and development and operation phases. Modern engineering education is oriented to provide future engineers with a sufficient background to be able to Conceive-Design-Implement-Operate.

The Safety Management System requires a structured Risk Management Process to be effective. In the technical fields where numerous potentially catastrophic risks exist, processes and procedures need to account not only for the hardware random failures but also of human errors. The technology has progressed to the point where the predominant safety risks are not so much the machine failures but that of the human interaction. Accidents are rarely the result of a single cause but of a number of latent contributing factors that when combined result in the accident. In the Aerospace industry, the operational risk to the fleet is assessed by the manufacturer and the operator independently and is used in safety and/or regulatory decision-making.

The Safety Management System (SMS) provides an environment where undesired events (proactively or reactively identified) are evaluated for the effect on safety using Risk Analysis. When the risk is evaluated, an interim risk reduction (mitigating action) may be applied to reduce the risk to a level that allows operations for a longer period before the safety issue is fully resolved. The risk assessment provides a means of evaluating the risk level and it may be difficult to quantify the “benefit” of interim mitigations that will reduce the risk. Prioritization of issues in the same risk category of the Risk Matrix is often simplified to a schedule and logistics basis of the final corrective action and often does not adequately show the benefit of the interim mitigating actions taken.

Integrated modular avionics (IMA) architectures host multiple federated avionics applications on a single platform and provide benefits in terms of size, weight, and power, which, however, leads to increased complexity, especially during the development process. To cope efficiently with the high level of complexity, a novel, structured development methodology is required. This paper presents a model-based systems engineering (MBSE) development approach for the so-called “distributed integrated modular architecture” (DIMA). The proposed methodology adapts the open-source Capella tool, based on the Architecture Analysis & Design Integrated Approach (ARCADIA) methodology, to implement a complete design cycle, starting with requirements captured from the aircraft level to streamline the development, culminating in the integration of an avionics application into an ARINC 653 platform.

With the high design/performance requirements in modern aircrafts, the need for a flexible airframe structural modeling strategy during the different phases of the airframe development process becomes a paramount. Hybrid structural modeling is a technique that is used for aircraft structural representation in which several Finite Element Modeling concepts are employed to model different parts of the airframe. Among others, the Direct Matrix Input at a Grid-Point (DMIG) approach has shown superiority in developing high fidelity, yet, simplified Finite Element Models (FEM's). While the deformation approach is a common choice for loads recovery in structures represented by stick models, using structural models simulated by the DMIG representation requires the adoption of a different approach for loads recovery applications, namely, the momentum approach.

Traceability has always been considered a useful but costly activity and different methods have been applied to reduce this cost. The current paper constitutes an attempt to improve these methods by introducing an optimal traceability process to be used in the context of RTCA DO-297 “Integrated Modular Avionics (IMA) Development Guidance and Certification Considerations”. The paper starts by comparing the definitions of traceability from DO-297 and the related development guidelines (i.e. ARP4754A, DO-254 and DO-178B). The paper continues by classifying the traceability methods recommended by the guidelines and introducing a performance criterion for optimal traceability based on category theory. This criterion addresses the possibility of information loss present in the current traceability methods. The paper proposes an optimal traceability process (i.e. that guarantees that information is not lost) and exemplifies it. The paper ends by recommending further enhancements.