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Integrating the seemingly divergent objectives of aircraft seat configuration is a difficult task. Aircraft manufacturers look to design seats to maximize customer satisfaction and in-flight safety, but these objectives can conflict with the profit motive of airline companies. In order to boost revenue by increasing the number of passengers per aircraft, airline companies may increase seat height and decrease seat pitch. This results in disaccommodation of a greater percentage of the passenger population and is a reason for rising customer dissatisfaction. This paper describes an effort to bridge this gap by incorporating digital human models, layout optimization, and a profit-maximizing constraint into the aircraft seat design problem. A simplified aircraft seat design experiment is conceptualized and its results are extrapolated to an airline passenger population.

The commercial turbofan trend of increasing bypass ratio and decreasing fan pressure ratio has seen its latest market entry in Pratt & Whitney's PurePower™ product line, which will power regional aircraft for the Bombardier and Mitsubishi corporations, starting in 2013. The high-bypass-ratio, low-fan-pressure-ratio trend, which is aimed at diminishing noise while increasing propulsive efficiency, combines with contemporary business factors including the escalating cost of testing and limited availability of simulated altitude test sites to pose formidable challenges for engine certification and performance validation. Most fundamentally, high bypass ratio and low fan pressure ratio drive increased gross-to-net thrust ratio and decreased fan temperature rise, magnifying by a factor of two or more the sensitivity of in-flight thrust and low spool efficiency to errors of measurement and assumption, i.e., physical modeling.

The RFID on Parts Project Team has recently completed and approved Spec 2000 Chapter 9, “RFID on Parts”. Once approved by the ATA e-Business Steering Group, this standard will allow for archiving and sharing part history information directly on RFID tags using the User Memory Bank. Using a structure similar to a File Storage System, this standard organizes tag data in a structured and indexed system so that information can be shared among all members of the supply chain. Now that high memory, passive tags are becoming available, when used in conjunction with the “RFID on Parts” standard, they make it possible to tag parts not just with an identification number, but with birth records, a full history of maintenance activities and user archives. Since end users and maintenance organizations will no longer need to rely solely on information retrieved from a centralized database, new processes and efficiencies can be realized.

The applicability, interpretation, and implementation of the testing requirements, in various aerospace and military tubing material specifications have caused confusion across the tubing industry. Despite the release of AMS specifications, procurement entities continue to purchase material produced to the older and often cancelled Mil-T specifications. In addition to mechanical properties, these specifications cover requirements including composition, grain size, heat treating, passivation, pressure testing, formability, non-destructive testing, and sampling frequency. Confusion may result for tubing producers who also supply commercial grade tubing having similar mechanical properties aerospace tubing. Ultimately it is the responsibility of the tubing manufacturer to understand the risks involved in meeting the requirements of the aerospace material specifications, both Military and AMS.

Whether it be in highly visible features like fascinating new infotainment systems or hidden behind the scenes in complex new hybrid powertrain controls, in-vehicle software is rapidly changing the way the automotive industry engages its vehicle-buying customers. In every application where a compelling new electronic solution is emerging, it is enabled by the convergence of in-vehicle software developed by different collaborating partners. As more and more component suppliers, vehicle OEMs, and technology vendors enter into collaborative software development projects with each other, a new set of technical and business challenges are showing collaborative software development to be a very distinctive proposition than traditional stand-alone development.

As aircraft programs currently ramp up, productivity of assembly processes needs to be improved while keeping quality, reliability and manufacturing cost requirements. Efficiency of the drilling process still remains an issue particularly in the case of CFRP/metal stacks: hot and long metallic chips are difficult to remove and often damage the surface of CFRP holes. Low frequency axial vibration drilling has been proposed to solve this issue. This innovative drilling process allows breaking up the metallic chips in such a way that jamming is avoided. This paper presents a case of CFRP/Ti6Al4V drilling on a CNC machine where productivity must be increased. A comparison is made between the current regular process and the MITIS drilling process. First the analysis and comparison method is presented. The current process is analyzed and its limits are highlighted. Then the vibration process is implemented and its performances are studied.

Constant swirls of innovative ideas are starting to push composites and hybrid metal-composite components for use in an ever expanding circle of products. Recent discoveries of Graphene/Au composites have invigorated innovations for its application to aerospace and space products. Attributes such as a low CTE, stiffness, and light weight attract other manufacturers of smaller products to use composites for enhanced performance and durability. The uses and economics of composites is an enormously broad subject. Examples of composite materials will be described in this paper to provide samples of applications selected for their far reaching potential to enhance product performance. Examples will also be presented to explain the application of carbon based composites where the product performance or application would not be possible without special materials.

Aerospace suppliers face the daunting task of constantly improving time-to-market, reducing cost of quality and turning compliance into a competitive advantage. Managing to these constraints while staying profitable is a challenge faced by the entire aerospace supply chain face today. The intent of this presentation is to share five lessons learned on how aerospace suppliers can optimize for these three constraints while growing their businesses. The first is electronically enabling traceability both within a multi-tier supply chains and throughout suppliers. Automating traceability at the shop floor improves quality management and accelerates compliance. Specific methodologies and metrics used to accomplish this will be provided. Second, lessons learned from implementing Manufacturing Execution Systems (MES) showing how shop floor visibility has a direct effect on supplier performance is illustrated with case studies and metrics.

The demand of fulfilling increasing Prime Customer requirements forces Tier 1 suppliers to continually improve their system solutions. Typically, this will involve integration of “state of the art” tools to afford the Tier 1 supplier a throughput and cost advantage. The subject “Production Optimization Approach” addresses the machine and process optimization of automated fastening machines in operation at customer factories. The paper will describe and focus on the main aspects of production optimization of existing machines to meet and exceed the required customer production and reporting criteria. Furthermore, the paper will present existing examples based on use of the established diagnostic tools

As a result of the increasing use of fibre reinforced plastic (FRP) components in a modern commercial aircraft, manufacturers are facing new challenges - especially with regards to the realisation of significant build rates. One challenge is the larger variation of the thickness of FRP components compared with metal parts that can normally be manufactured within a very narrow thickness tolerance bandwidth. The larger thickness variation of composite structures has an impact on the shape of the component and especially on the surfaces intended to be joined together with other components. As a result, gaps between the components to be assembled could be encountered. However, from a structural point of view, gaps can only be accepted to a certain extent in order to maintain the structural integrity of the joint. Today's state of the art technologies to close gaps between FRP structures comprise shimming methods using liquid and solid shims.

In an attempt to be more flexible and cost effective, Aerospace Manufacturers have increasingly chosen to adapt a manufacturing style which borrows heavily from the Automotive industry. To facilitate this change in methodologies a system for locating robots has been developed which utilizes cameras for both locating and guidance of a mobile platform for a robot with drilling and fastening end effector.

Polyurethane (PU) foam is used for many automotive applications with the benefits of being lightweight, durable, and resistant to heat and noise. Applications of PU foams are increasing to include non-traditional purposes targeting consumer comfort. An example of this is the use of PU foam between the engine and engine cover of a vehicle for the purpose of noise abatement. This addition will provide a quieter ride for the consumer, however will have associated environmental impacts. The additional weight will cause an increase in fuel consumption and related emissions. More significant impacts may be realized at the end-of-life stage. Recycling PU foams presents several challenges; a lack of market for the recyclate, contamination of the foams, and lack of accessibility for removal of the material.

Career paths are not something that one can predict. They are as much about being in the right spot at the right time with the desired skill set as they are about having a detailed, calculated plan. How does one go from being a young Original Equipment Manufacturer (OEM) test engineer to being an airline Senior Vice President of Safety, Security and Compliance and the joint industry/FAA co-chair of the Commercial Aviation Safety Team? It is a bit unusual that a non-pilot ends up on an airline Operations Specification listed as the Federal Aviation Regulations (FAR) Part 119 Director of Safety for one of the largest airlines in the world. Engineering background and experience were key stepping stones on that journey along with a healthy dose of skepticism. An initial assignment to make an airline's safety program robust, credible and data driven, much like the very successful aircraft reliability programs, set the direction and path forward.

Current methods of life cycle assessment (LCA) include input-output (IO) models and process-based LCA. These methods either require excessive effort and time to reach a conclusion (process LCA) or do not adequately model how a change in a product's design will affect the environmental footprint (IO LCA). A variation of process-based LCA developed specifically for aircraft is presented in this study. A tool implementing this LCA, “qUWick,” is rapid and easily applicable to multi-disciplinary design optimization of aircraft. Models developed for the material production, manufacturing, usage, and end-of-life of an aircraft are examined. Outputs of qUWick are discussed for future air vehicles. When compared to process LCAs with similar boundaries, qUWick gives similar results, however qUWick models several stages of an aircraft's life cycle more accurately than other aircraft process-based LCAs.

This paper introduces a novel approach in order to compare different eco design practices considering the value network of stakeholders. The proposed decision tool framework in this study helps manufactures in early stage of design to select a portfolio of eco design techniques to maximize the value perceived by all stakeholders in a dual life cycle approach including the business product life cycle as well as physical life cycle. A portfolio selection approach has been used to maximize the network value of stakeholders considering the life cycle cost and risk of techniques while satisfying the diversity of allocation resources on eco design practices based on strategic objectives of manufacturers. The dynamic characteristic of stakeholder's network as the result of implementing the different eco design techniques has also been considered in order to evaluate the synergy in stakeholder's network.

This paper presents a set of numerical computations with different turbulence model on an air jet flowing tangentially over the curved surface. It has been realized that jet deflection angle and the corresponding thrust are important parameter to determine with great care. Through the grid independence analysis, it has been found that without resolution of the viscous sub-layer, it is not possible to determine the computationally independent angle of jet deflection and boundary layer thickness. The boundary layer analysis has been performed at different radius of curvature and at jet Reynolds number ranging from approximately about 2400-10,000. The boundary layer thickness has been determined at the verge of separation and found a relation with the radius of curvature and jet Reynolds number. The skin-friction coefficient has been also studied at the verge of separation in relation to the surface radius and jet Reynolds number.

This study investigates the self-adjusted cutting parameter technique to improve the drilling of multi-stacked material. The technique consists in changing the cutting strategy automatically, according to the material being machined. The success of this technique relies on an accurate signal analysis, whatever the process setting. Motor current or thrust force are mostly used as incoming signals. Today, analyses are based on the thresholding method. This consists in assigning lower and upper limits for each type of material. The material is then identified when the signal level is stabilized in between one of the thresholds. Good results are observed as long as signal steps are significantly distinct. This is the case when drilling TA6V-CFRP stacks. However, thrust force level remains roughly unchanged for AA7175-CFRP stacks, leading to overlapping thresholds. These boundary limits may also change with tool geometry, wear condition, cutting parameters, etc.

Fault-tolerance in commercial aircraft applications is typically achieved by redundancy. In such redundant systems the primary component is checked before the start of a flight to see if it operates correctly. The aircraft will not take off unless the primary is functioning. Airplane manufacturers must certify the airplane systems to be safe for flight. One means of safety certification is by safety analysis which shows that the probability of failure in a typical flight is bounded. The probability bound requirement for a system is based on the criticality of system failure. Usually backup components are checked at intervals that span multiple flights. The first backup may be checked more frequently than the second or higher levels. This leads to flights where the system may have latent faults in the backup components. The probability of failure in such cases varies from flight to flight due to the different exposure times for components in the system.

Industrial robots are well introduced into automated production processes. Their mechanical design is dominated by some major key factors like required flexibility, different payload demands, working range, working speed, combination with different working tools and robot costs. The final achieved position accuracy of the robot tool centre point (TCP) is based on the combination of these key factors. In general, the smallest movement steps and the repeatability of robots are much lower than the absolute achievable accuracy. The positioning results and especially the programmed paths of the TCP show relatively large differences between the programmed nominal paths related to the final achieved movements in reality. These differences can be detected using the Absolute Tracker with its very high dynamic performance, especially if the 6DoF capability is included.

Laser Based Powder Bed Fusion, a specific application of additive manufacturing, has shown promise to replace traditionally fabricated components, including castings and wrought products (and multiple-piece assemblies thereof). In this process, powder is applied, layer by layer, to a build plate, and each layer is fused by a laser to the layers below. Depending on the component, it appears that only 3-5% of the powder charged into the powder bed fusion machine is fused. Honeywell’s initial part qualification efforts have prohibited the reuse of powder. Any unfused powder that exits the dispenser (i.e., surrounds the build or is captured in the overflow) is considered used. In order for the process to be broadly applicable in an economical manner, a methodology should be developed to render the balance of the powder (up to 97% of the initial charge weight) as re-usable.