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Many uncertainties in an in-flight ice shape prediction are related to convection heat transfer coefficient, which in turn depends on the flow, turbulence and laminar/turbulent transition models. The height of ice roughness element used to calculate the Equivalent Sand Grain Roughness height (ESGR) is a very important input of the turbulence model as it strongly influences the shape of the accreted ice. Unfortunately, for in-flight icing, the ESGR is unknown and generally calculated using semi-empirical models or empirical correlations based on a particular ice shape prediction code. Each ice shape prediction code is unique due to the models and correlations used and the numerical implementation. Ice roughness correlations do not have the same effect in each ice shape prediction code. A new approach to calculate the ESGR correlation taking into consideration the particularities of the ice shape prediction code is developed, calibrated and validated.

This paper proposes a new methodology to conduct thermal analysis in the conceptual phase of the aircraft development process. Traditionally, thermal analysis is conducted after the system architecture has already been defined. The aircraft system thermal environment evaluation may lead to late design changes that can have a significant impact on the development process. To reduce the risk of late design changes, thermal requirements need to be defined and validated in the conceptual design phase. This research paper introduces a novel multi-level modeling strategy based on a bottom-up approach. It proposes an automatic geometrical simplification procedure for Computational Fluid Dynamic (CFD) analysis, a methodology for the generation of analytical correlations based on highly detailed methods, and a thermal risk assessment approach based on dimensionless numbers.

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.

Advanced commercial aircraft increasingly use more composite or hybrid (metal and composite) materials in structural elements and, despite technological challenges to be overcome, composites remain the future of the aviation industry. Composite and hybrid aircraft today are equipped with digital systems such as fly by wire for reliable operations no matter what the flying environment is. These systems are however very sensitive to electromagnetic energy. During flight, aircraft can face High Intensity Radiated Fields (HIRF), static electricity, or lightning. The coupling of any of these threats with airframe structure induces electromagnetic energy that can impair the operation of avionics and navigation systems. This paper focuses on systems susceptibility in composite aircraft and concludes that the same electromagnetic rules dedicated to all metal aircraft for systems and wiring integration cannot be applied directly as such for composite aircraft.

Implementing Design for Environment (DfE) into the design process requires a strategic integration. Furthermore, as DfE is continuously evolving, flexible processes need to be implemented. This article focuses on the integration of DfE into an optimization framework with the objective of influencing next-generation aircraft. For this purpose, DfE and Structures groups are developing together a set of new environmental indicators covering all life cycle stages of the product by coupling a list of yes/no questions with an environmental matrix. The following indicators are calculated: Regulation risk, Impact of manufacturing the part, CO2 emissions and Recyclability potential. These indicators will be used as constraints in the multi-disciplinary design optimization (MDO) framework, meaning that the structure will be designed while complying with environmental targets and anticipating future regulation changes.

Current transport aircraft are mature systems, thus require increased fidelity at the beginning of the design process to allow further optimization. Furthermore, a desire exists to explore unconventional aircraft configurations at the conceptual level. This has motivated the development of a tool which effectively manages the trade-off between high-fidelity levels, flexibility and short turn-around times. This paper presents a CATIA V5-based parametric aircraft geometry modeler developed by Bombardier Aerospace. The aim of the tool is to provide consistent high-fidelity geometric data early in the conceptual aircraft design process. The intended near-term use of the modeler is two-fold: during the early design phase, the modeler computes geometric data such as areas, volumes, ESDU aircraft parameters, etc. In the competitive analysis domain, the tool provides a high-quality three-dimensional model with manageable effort.

The lightning represents a fundamental threat to the proper operation of aircraft systems. For aircraft protection, Electromagnetic Compatibility requires conductive structure that will provide among all, electromagnetic shielding and protection from HIRF and atmospheric electricity threat. The interaction of lightning with aircraft structure, and the coupling of induced energy with harnesses and systems inside the airframe, is a complex subject mainly for composite aircraft. The immunity of systems is governed by their susceptibility to radiated or conducted electromagnetic energy. The driving mechanism of such susceptibility to lightning energy is the exposure to the changing magnetic field inside the aircraft and IR voltage produced by the flow of current through the structural resistance of the aircraft. The amplitude of such magnetic field and IR voltage is related to the shielding effectiveness of the aircraft skin (wiremesh, composite conductivity).

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.

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.

During the course of an aircraft program, cost and weight savings are two major areas demanding constant improvements. An Integrated Product Development Team (IPDT) was set to the task of proposing potential improvements to an aircraft under development. From a list of potential parts, the IPDT selected one which was considered as the most suitable to leverage a co-curing process. In the aircraft manufacturing industry, any major modification to a part design should follow the program's means of compliance to certification. Furthermore, to demonstrate the new design's safety, sizing methodology and all supplementary testing must fit in the certification strategy. The IPDT approach was used to ensure the maturity of both process and part. Indeed, a mature turnkey solution can be implemented quickly on the shop floor. This IPDT approach is detailed in another SAE 2013 technical paper entitled: “A Novel Approach for Technology Development: A Success Story” [3].

Bombardier faced new manufacturing process challenges drilling and fastening CSeries* aircraft panels with multi-material stacks of composite (CFRP), titanium and aluminum in which Gemcor responded with a unique, flexible CNC Drivmatic® automatic fastening system, now in production at Bombardier. This joint technical paper is presented by Bombardier, expounding on manufacturing process challenges with the C Series aircraft design requirements and Gemcor presenting a unique solution to automatically fasten CFRP aft fuselage panels and aluminum lithium (Al Li) cockpit panels with the same CNC Drivmatic® system. After installation and preliminary acceptance at Bombardier, the CNC system was further enhanced to automatically fasten the carbon fiber pressure bulkhead dome assembly.

From purchase order to production womb-to-tomb in 5 months to the day, Bombardier's Fuselage Assembly line was upgraded and made into a fuselage automated assembly pulse line. This was accomplished with a factory move of the assembly line while maintaining production of this legacy line without missing one aircraft. Early in 2012, a bold decision was made to change the plan from a manual process to an automated process and implemented on schedule. This was applying automation to a legacy aircraft assembly line. It worked. Both technology and recurring cost savings will be addressed in this paper.

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.

The aging of the world population, and call for greater equality in access to public environments has led to an increase in design for persons with reduced mobility (PRM). There are numerous physical and operational constraints and parameters to overcome when designing a successful and marketable PRM environment. Each program evaluates what is to be considered reasonable based on these guidelines (cost, weight, manufacturability, airframe curvature, footprint required, regulations, and usability). However, there are other less tangible parameters to address. For example, what level of dignity or level of privacy does the PRM environment allow? Does the design require additional assistance to access, or can those who are able make independent use of the environment? Most aircraft manufacturers and design entities have recognized the need to improve accessibility aboard single aisle commercial aircraft (Airbus 320 family, Boeing 737, Embraer 190, Bombardier CSERIES).

This paper presents a methodology for conceptual aircraft design to evaluate the space available for systems (top-down approach) and to estimate the space required for critical components impacting the aircraft configuration (bottom-up approach). The presented top-down approach introduces the concept of “equivalent design volume”, including the space required for systems and the associated empty space to access, maintain and ventilate them. This approach enables an early feasibility check for aircraft configuration exploration regarding the integration and installation of systems, without having to detail the system architecture. In complement, the bottom-up approach introduces the estimation of the required dimensions for critical components. Here, the example of the flight control actuators integration in the wing tip is presented.

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.

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.

In order to guarantee systems immunity, lightning induced electromagnetic energy has to be lower than the system's susceptibility threshold. This can be achieved, if the aircraft structure provides a good protection against lightning current as well as against its electromagnetic induced field. Moreover such a structure is also required to constitute a ground plane that guarantees very low common mode impedance between all grounded systems in order to keep them at the same electrical potential. The interaction of lightning with aircraft structure, and the coupling of induced energy with harnesses and systems inside the airframe, is a complex phenomenon, mainly for composite aircraft. Composite structures are either not conductive at all (e.g., fiberglass) or are significantly less conductive than metals (e.g., carbon fiber).

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.

In civil aviation the main driver for Structural Health Monitoring (SHM) is to provide maintenance and ownership benefits. The maintenance benefits are defined in terms of improving maintenance planning, increasing inspection intervals and reducing inspection cost. The ownership benefits can be measured in residual value and life extension. In this paper different aspects of SHM implementation are discussed for fatigue monitoring and fatigue damage sensing with a consideration of minimizing challenges for SHM implementation. First, the current Fatigue Monitoring implementation scenarios for the most representative agile military aircraft are reviewed. In the following some aircraft utilization results obtained from analyzing different airlines are presented. The obtained results show a better possibility of categorizing fleet of an airline in comparison with agile military aircraft.