Rubber – a loosely cross-linked network of polymer chains that when strained to high levels will forcibly return to at or near it original dimensions. This course is designed to provide the participant with a thorough understanding of rubber’s engineering characteristics. This class will introduce the various sources of rubber, both natural and synthetic. The class will contrast the differences between rubber and plastics; including thermoplastic rubber. Detailed discussions on how to select the correct rubber polymer for the application, highlighting the pros and cons of each major rubber type.
Silicone rubber is comprised of inorganic-organic polymers. These materials consist of an inorganic backbone with organic side groups attached to silicon atoms. This family of polymers possesses unmatched versatility giving the formulator and user multiple forms and methods to cross link the polymers into rubber materials having the widest service temperature range of any rubber material. This course is designed to provide the participant with a thorough understanding of silicone’s engineering characteristics.
The avionics hardware industry world-wide is now commonly required to follow DO-254 Design Assurance Guidance for Airborne Electronic Hardware for literally all phases of development: Safety, Requirements, Design, Logic Implementation, V&V, Quality Assurance, etc. The DO-254 standard is a companion to the software DO-178B standard; however, there are many differences between hardware and software which must be understood. This basic course introduces the intent of the DO-254 standard for commercial avionics hardware development.
For aircraft structures, mechanical assembly using fasteners remains the most common technology. The setting of the numerous fasteners requires a large number of drilling operations. In the case of CFRP/TA6V stacks, the drilling still remains a technological challenge. Indeed the high-quality requirements by the aeronautic standards are limited by the fast damaging drilling tool phenomena. For TA6V, the forced assisted drilling provides a breakthrough technology. An axial forced oscillating displacement on the feed direction of the tool allows the creation of segmented chips. Those small chips are then easily evacuated from the cutting area using a vacuum device. This allows the improvement of the hole’s roughness and mastering the burr creation at the exit of the hole. The lubrication process is also enhanced during the exit sequence of the tool. For the CFRP/TA6V configuration, the segmented geometry of the chip avoids the roughness degradation on the composite part of the stack.
Traditional Trailing Edge (TE) assembly that utilise fixtures for accurate positioning of aircraft (a/c) parts do not allow for removal of specific tooling from the fixtures to travel with the TE, post assembly. Instead, the tooling that positions all the primary a/c assembly datums generally utilise precision pins of various sizes that index and clamp the a/c ribs. Often it is difficult to remove the pins post assembly before the spar can be taken out of the fixture. Use of hammers is common place to hit pins out of holes which is less than ideal considering the a/c parts can be fragile and the tooling is precision set. Also, the Main Assembly Fixture (MAJ) that will receive the TE will inevitably need to relocate some if not all the primary a/c ribs and therefore will most likely be subject to some amount of persuasion.
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.
ASRP (Assembly Simulation of Riveting Process) software is a special tool for modelling assembly process for large scale airframe parts. On the base of variation simulation, ASRP provides a convenient way to analyze, verify and optimize the arrangement of temporary fasteners. During the airframe assembly process certain criteria on the residual gap between parts must be fulfilled. The numerical approach realized in ASRP allows one to evaluate the quality of contact on every stage of the assembly process and solve verification and optimization problems for temporary fastener patterns. The paper is devoted to description of several specialized approaches that combine statistical analysis of measured data and numerical simulation using high-performance computing for optimization of fastener patterns, calculation of forces in fasteners needed to close initial gaps and identification of hazardous areas in junction regions.
This paper will use actual examples from aircraft recently introduced into service, to describe the main advantages of changing from the currently used metallic bearings, to composite bearings. Abstract: The introduction of composite bearing in a recently introduced twin aisle aircraft has resulted in: • Weight saving, by replacing bronze bearings with plastic bearings • Lowering of the particle count in the shock absorber oil, (Reduced contamination with metal particles) leading to reduced wear on seals and bearings. Qualification testing showed that Composite Bearings are able to provide longer service life than bronze bearings.
Within the current part production of carbon fiber parts a lot of manual work is included for sorting and kitting of automatic cut plies. This is required due to the high raw material costs and enables a good utilization of the materials. Automation of this non-value adding process will be a big benefit for the part production. The high variety of shapes and the different materials to be processed are complex boundary conditions, which are to be overcome. Broetje is in development of handling systems and automation solutions, which are used for a high variety of materials as well as for a high variety of shapes. These systems are meant to be an add-on for existing cutting tables as well as for fully integrated production systems with downstream automation equipment like draping hoods. Mayor challenges to overcome are safe gripping capabilities, detection of #non-cut fibers, high variety of shapes, complex logistic management. These challenges are addressed with Broetje’s ASK Solution.
In this study, we focus on an electric air-cycle system in an electric aircraft, where the system has an electric compressor instead of a hydraulically-operated oil-based compressor. The electric compressor consumes the power to compress the rarefied air outside and take it in the system. The air goes through the air-cycle as a working fluid to exchange the heat and work. The main purpose of the air-cycle is to adjust the temperature and pressure in a cabin. Therefore, the working fluid of the air repeats compression and expansion. The working fluid passing through the cabin absorbs heat from the passengers and avionics. After that, the air is discharged outside with higher heat level and pressure levels. This means that the discharged air has a potential energy to recover the power consumption in the electric compressor.
The interest of selective laser melting technology for aerospace parts is very high due to their high complexity and their freedom of design which allow functions integration. However, the competitiveness of Laser Beam Melting (LBM) machines for aerospace industry is limited by two major road blocks. On the one hand, basic parametric set sold with LBM machines are more oriented to historical qualification than productivity rates. For instance, the ongoing qualification on EOS M290 by AIRBUS COMMERCIAL AIRCRAFT only enables us to produce a hundred pieces per machine per year. On the other hand, wasted times between two consecutive manufacturing batches are significant and are impacting the yearly output of the machines. The present project focuses on two activities, focusing on the largest available machines, XLINE2000R and M400, in order to maximize the amount of pieces per build.
The requirements of the AS9120, Rev. B, EN9120B and JIAQ9120B Standards have significantly changed and are based on the NEW ISO9001:2015 Standard. This two-day training program is designed to provide individuals with the knowledge necessary to understand and comprehend the NEW requirements described in AS9120 Rev. B, Quality Management Systems - Requirements for Aviation, Space, and Defense Distributors. The course includes classroom instruction combined with class exercises to further reinforce concepts and definitions now required by the standard.