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Several new technologies are now emerging to improve adhesive supply and formulation along with surface treatments that have the potential to offer significant improvements to both surface energy and cleanliness [3]. Additionally, the miniaturisation of laboratory techniques into portable equipment offers potential for online surface energy and chemical analysis measurement for use as quality control measures in a production environment. An overview of newly available technology is given here with several devices studied in further detail. Technologies assessed further in this paper are; portable surface contact angle measurement, ambient pressure plasma cleaning, portable FTIR measurement and adhesive mixing equipment. A number of potential applications are outlined for each device based on the operational technique. The practical aspects of implementation and the perceived technology readiness levels for operation, implementation and results are also given.

Electroimpact has recently produced a high-speed fuselage panel fastening machine which utilizes an all-electric, CNC-controlled squeeze process for rivet upset and bolt insertion. The machine is designed to fasten skin panels to stringers, shear ties, and other internal fuselage components. A high riveting rate of 15 rivets per minute was achieved on the first-generation E7000 machine. This rate includes drilling, insertion, and upset of headed fuselage rivets. The rivets are inserted by a roller screw-driven upper actuator, with rivet upset performed by a lower actuator driven by a high-load-capacity ball screw. The rivet upset process can be controlled using either position- or load-based feedback. The E7000 machine incorporates a number of systems to increase panel processing speed, improve final product quality, and minimize operator intervention.

For decades optical camera systems have been used by Broetje-Automation to locate pilot holes and find product orientation on NC-controlled positioner systems. Measurement tolerance requirements were and are in the range of +/− 0.2 mm. Recent developments enhance the sensor technology function from pure hole detection to new features like Fastener Head Height Measurement and Countersink Diameter Measurement. While head height measurement has to go 3D by enhancing the planar sensors to head protrusion measurement, the Countersink measuring tolerances are much smaller than “simple” hole detection, in fact require more than a magnitude tighter tolerances. This paper will present how Broetje-Automation solved the issue of a 20 plus fold accuracy increase, the 3D capability of the one eyed camera and all accompanied by a more robust evaluation software.

Blade tip clearance is a key design parameter for gas turbine designers. This parameter is often measured during engine testing and development phases as part of design validation but has yet to be utilized during normal engine fleet operation. Although blade tip clearance measurements are often mentioned for fleet operation in the context of active clearance control, the use of blade tip clearance measurements can provide an additional benefit for engine health monitoring. This paper explores the use of blade tip clearance sensors for engine condition monitoring of hot section blades. Blade tip clearance, especially in the first stage turbine, has an impact on exhaust gas temperature. The use of tip clearance measurements can provide supplementary information to traditional EGT measurements by providing a direct measurement of wear on the blade tips.

Experimental study is performed to analyze the shedding behavior of droplets with different shear flow speeds typical of those in the flight conditions. Droplet shedding phenomena has significant effect on ice accumulation on critical components such as airfoil and nacelle. In order to mimic this scenario experimental set up is designed to generate shear flow as high as 90m/s. The high shear effect is combined to the surface wettability impact by using hydrophilic and superhydrophobic surfaces. It is shown that the wetting length of the droplet on hydrophilic surface increases by shear speed while on the superhydrophobic surface a drastic reduction on wetting length is detected. Furthermore, it is observed that the droplet is detached from the superhydrophobic surface with moderate shear speeds.

Unlike the conventional bleed-air method, using electro-thermal anti-/de-icing methods to completely evaporate all of the supercooled water droplets that collide with the leading edge wing surface of aircraft flying in a freezing environment is not easy in terms of technical feasibility and energy efficiency[1]. If the leading edge is warm enough to stay free from frozen water droplets, the water moves backward while still maintaining the liquid phase. The droplets may freeze somewhere on an unheated surface after being halted for some reason and stick on the surface. Ice gradually accumulates as this process is repeated. Therefore, liquid water must be removed from the surface as soon as possible if the electrothermal method is employed for icing prevention. One answer to this problem is coating the surface with a superhydrophobic paint.

The tenets of IEC 61300-3-35 have influenced and contributed to numerous standards. These include: a.) the importance of cleaning the fiber optic connection, b.) the concept of diameter of debris or contamination, and, c.) the area of the end face to be cleaned, d.) methods of cleaning. As capacity and bandwidth expand, deployments updated, and new technicians trained, a clear understanding of several other tenets of precision cleaning the connection may also be considered. There are many types of debris and contamination. Some are dry Figure-1 and others are fluidic Figure-2. Debris on an end face may also be present in combination Figure-3. The cleaning procedure should strive to be a first time event. A best practice procedure can be identified that does not require multiple techniques and numerous attempts.

1 The current pressure across the entire aerospace industry to reduce operating costs and increase efficiency has arguably never been greater. Thus the need to improve parameters such as availability and reliability, and increase the tools and services associated with more efficient aircraft operations and sustainment is now paramount. Moreover, these improvements are seen by many as important factors that define the differentiation and competitiveness of not only current but also future aircraft fleets. The paper will focus on some of the opportunities for OEMs that arise from implementing Integrated Vehicle Health Management (IVHM) systems on their platforms and the challenges associated with evaluating the costs and benefits of their implementation and operation.

Electroimpact's newest riveting machine features a track-style injector with Bomb Bay Ejection Doors. The Bomb Bay Ejection Doors are a robust way to eject fasteners from track style injector. Track style injectors are commonly used by Electroimpact and others in the industry. Using the Bomb Bay Doors for fastener ejection consists of opening the tracks allowing very solid clearing of an injector when ejecting a fastener translating to a more reliable fastener delivery system. Examples of when fastener ejection is needed are when a fastener is sent backwards, when there are two in the tube, or when a machine operator stops or resets the machine during a fastening cycle. This method allows fasteners to be cleared in nearly every situation when ejecting a fastener is required. Additional feature of Electroimpact's new injection system is integrated anvil tool change.

The aeroelastic design of highly flexible wings, made of extremely light structures yet still capable of carrying a considerable amount of non-structural weights, requires significant effort. The complexity involved in such design demands for simplified mathematical tools based on appropriate reduced order models capable of predicting the accurate aeroelastic behaviour. The model presented in this paper is based on a consistent nonlinear beam model, capable of simulating the unconventional aeroelastic behaviour of flexible composite wings. The partial differential equations describing the wing dynamics are reduced to a dimensionless form in terms of three ordinary differential equations using a discretization technique, along with Galerkin's method. Within this approach the nonlinear structural model an unsteady indicial based aerodynamic model with dynamic stall are coupled.

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.

The first cross-industry guidelines for the implementation of structural health monitoring for aerospace applications have been created as a SAE International Aerospace Recommended Practices document: SAE ARP 6461 ‘Guidelines for Implementation of Structural Health Monitoring on Fixed Wing Aircraft’ [1]. These guidelines have brought together manufacturers, operators / users, systems integrators, regulators, technology providers and researchers to produce information on the integration of SHM into aircraft maintenance procedures, generic requirements and advice on validation, verification and airworthiness. The take-up of SHM in the aerospace industry has been slow, in part due to the lack of accepted industry practices surrounding not just the technology itself (sensors and sensor systems) but also the associated issues arising from the introduction of new methods into aircraft maintenance.

Aerospace manufacturing requires efficient manufacturing processes. Composite materials are extensively used and manufacturing processes must evolve to overcome composite constraints for manufacturing and joining. Bolting is an extended joining process for composite materials in which a deformable blind bolt is stressed until joining forces are high enough to cause bolt breakage and ensure sufficient compression forces in the joint. Among bolting methods, blind bolting is an efficient composite joining method that enables the construction of aerospace composite structures accessing joints from a single side of the joint (front side), thus allowing for constructing closed structures where accessing the back side (blind side) is not possible. However, not being able to access the deformed head at the blind side prevents to perform a quality control and ensure a proper bolt deformation and a proper installation.

Metal matrix composites (MMCs) exhibit superior characteristics such as low weight, high stiffness, and high mechanical and physical properties. Inheriting such an outstanding combination of specifications, they are nowadays considered as the promising materials in the aerospace and biomedical industries. However, the presence of high abrasive reinforcing particles in MMCs leads to severe manufacturing issues. Due to the tool-particle interactions which occur during the machining of MMCs, high tool wear and poor surface finish are induced and those elements are considered as the main drawbacks of cutting MMCs. In this study, dry turning experiments were conducted for two different inserts and coated carbide on a bar of titanium metal matrix composite (Ti-MMC). Semi-finishing machining is operated with cutting parameters based on the tool supplier's recommendations which were not fully optimized. The maximum flank wear length (VBBmax) was selected as the tool wear criteria.

The need for efficient manufacturing approaches has emerged with the increasing usage of composites for structural components in commercial aviation. Resin Transfer Molding (RTM), a process where a fiber preform is injected with resin into a closed tool, can achieve high fiber content required for structural components as well as improved dimensional accuracy since all surfaces are controlled by a tool surface. Moreover, RTM is well suited for parts that can be standardized throughout the aircraft, such as a fuselage frames and stringers. The objective of this investigation is to develop a preforming approach for a C-Shaped Fuselage frame. Two approaches are proposed: tri-axial braiding and hand lay-up of Non-Crimp Fabrics. The fiber architecture of the basic materials as well as the complete preforms is explained. The necessary preforming operations are detailed. The quality control measurement of fiber orientation and thickness are presented.

On September 30, 2011, certification authorities released Advisory Circular 20-174[1], Development of Civil Aircraft and Systems, which recognizes the Society of Automotive Engineers (SAE) Aerospace Recommended Practice (ARP) 4754A and the European equivalent ED-79A [2], in order to address “the concern of possible development errors due to the ever increasing complexity of modern aircraft and systems.” ARP4754A/ED-79A describes a process of development assurance which helps reduce the risk of design errors in the development of aircraft systems. This process is necessary for complex systems not easily comprehended by deterministic analyses or tests. This ARP was developed “in the context of Title 14 of the Code of Federal Regulations (14 CFR) part 25,” a category which includes complex systems such as full fly-by-wire flight controls. However, this paper shows that such systems are the exception to most, recent civil airplane designs.

This paper is devoted to a method of creating of the automated ballonet system for pressure control inside an airship envelope. Along with the study of the effects of the positional control system parameters, the authors develop novel control scheme. It is based on a new hybrid controller, which combines positional approach to forming the output control signal with a contour of continuous correction of input signal, which defines the pressure drop on the surface of the envelope as a function of the flight altitude. This approach allows reducing the effect of self-oscillations of airship envelope internal pressure on the flight altitude. In order to prove the new approach the mathematical model is being obtained. The results of the derivation and simulations of the control system operation are presented in this paper.

We live in an era of increasing twin-engine commercial airplane operations, with large and very quiet high bypass ratio engines. At the same time, due to several decades of increased attention to the environment, we have large and increasing hazardous species bird populations. These trends, when combined, are not a prescription for continued assurance of a remarkable and enviable safety record for commercial aviation. Therefore, greater diligence must be placed on the evaluation of the current and future aviation wildlife hazard. We have some new weapons in this fight for greater capability to live with this situation. The basic problem is that different databases are populated independently from one another and often contain conflicting, contradictory, and erroneous data. Databases that were used individually, but not necessarily combined, are being utilized in a conjoined methodology to give us a better picture of the actual risk involved.

Reducing greenhouse gas emissions to limit global warming is becoming one of the key issues of the 21st century. As a growing contributor to this phenomenon, the aeronautic transport sector has recently taken drastic measures to limit its impact on CO2 and pollutants, like the aviation industry entry in the European carbon market or the ACARE objectives. However the defined targets require major improvements in existing propulsion systems, especially on the gas generator itself. Regarding small power engines for business aviation, rotorcrafts or APU, the turboshaft is today a dominant technology, despite quite high specific fuel consumption. In this context, solutions based on Diesel Internal Combustion Engines (ICE), well known for their low specific fuel consumption, could be a relevant alternative way to meet the requirements of future legislations for low and medium power applications (under 1000kW).

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.