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CFRP has been widely used in aerospace industries because of its high strength-to-weight ratio. However, drilling CFRP laminates is difficult due to the highly abrasive nature of the carbon fibers and low thermal conductivity of CFRP. Therefore for the manufacturers it is a challenge to drill CFRP materials without causing any delamination within the high quality requirements while also considering the costs of the process. This paper will discuss the process of drilling CFRP-Al stack ups within tight tolerances using a seven axis drilling robot. All components required for drilling are integrated in the drill end-effector. The pressure foot is extended in order to clamp the work piece, and then holes are drilled. The drilling process has four steps: moving to the fast approach level, controlled drill feed, countersink depth reach and drill retract. The cutter diameter range chosen for this paper is Ø 4.0 mm and Ø 7.9 mm.

A hybrid drilling process of multi material stacks with one shot drilling recently emerge as an economical and time efficient method in aerospace industry. Even though the comprehensive experience and knowledge is available for the cutting parameters of composites and metals alone, significant gap exist for the hybrid drilling parameters. Determination of these parameters such as feed rate, spindle speed and pecking depth has vital importance so as to provide a robust and optimal process to ensure dimensionally high quality, burr and delamination free holes. Main challenge of hybrid drilling operation is to obtain required hole diameter with adequate homogeneity and repeatability. In this study, effect of cutting parameters on dimensional hole quality was investigated. In addition to the hole diameter tolerances, CFRP hole enlargement phenomena which is encountered as a specific drawback of metal-exit stack configurations is also addressed within the scope of this study.

In the current study, continued efforts to improve a computational in-flight ice accretion prediction tool are introduced together with obtained results. The computational tool follows the usual procedure for computing ice shapes around three-dimensional bodies like wings, intakes, etc., i.e., flow-field calculation, droplet trajectory determination, droplet collection efficiencies calculation, convective heat transfer coefficient distribution computation and finally ice accretion rates determination using the Extended Messinger Method. Finally, integration of ice accretion rates over time yields the ice shapes and the final geometry. The emphasis in this study is on parallel computation of the droplet trajectories using the Langrangian approach.

Ever increasing process applications inspire us, as suppliers of aircraft, structural-assembly, and equipment to design innovative and modular, manufacturing cells in compliance with modern specifications. The result is the new flexible C-Frame Panel Assembly Cell (CPAC) Bulkhead riveting System. This paper describes how benchmarks for flexible automated drilling and fastening are being achieved with the CPAC.

Accurate simulation of icing is important for the assessment of several potential icing scenarios and complex icing regulations. However, performing all possible icing scenarios is a demanding process in terms of computational cost, especially when modification of the geometry due to ice accretion is required. Additionally, aircraft icing safety assessment necessitates an evaluation of the accumulated ice. Thus, numerical representation of the non-linear and complex geometries is essential for the parametrization of this ice. Indeed, surrogate models have the capability of predicting these complex, non-linear shapes. For this purpose, a method for ice accretion prediction on a selected airfoil, NACA 22112, is proposed in this study with different surrogate models that will later be used for fast prediction in 6DOF simulations to directly evaluate its effects on aerodynamic performance during flight.

Distinct parts of the aircraft may be exposed to different icing conditions due to varying flow and ambient conditions around them. These differences can be easily noticed, especially when icing conditions on the external surface and inside the engine air intake are compared for a jet aircraft. In this paper, the icing conditions around these parts are matched to between them. The purpose of this comparison study is to evaluate the functionality of ice detectors, located inside the air inlets, in detecting icing conditions around external surfaces as well. These systems provide information to the flight crew and/or airplane systems concerning inflight icing. On jet fighter or trainer type aircraft, they are generally located inside the engine air intake that serve as a warning equipment for icing risks on the aircraft engine itself. Sometimes, their warnings are also valid for intake lip ice detection if they are properly located.

The E7000 riveting machine installs NAS1097KE5-5.5 rivets into A320 Section 18 fuselage side panels. For the thinnest stacks where the panel skin is under 2mm (2024) and the stringer is under 2mm (7075), the normal process of riveting will cause deformation of the panel or dimpling. The authors found a solution to this problem by forming the rivet with the upper pressure foot extended, and it has been tested and approved for production.

Ice crystal ingestion to aircraft engines may cause ice to accrete on internal components, leading to flameout, mechanical damage, rollback, etc. Many in-flight incidents have occurred in the last decades due to engine failures especially at high altitude convective weather conditions [1]. Thus, in the framework of HAIC FP7 European project, the physical mechanisms of ice accretion on surfaces exposed to ice-crystals and mixed-phase conditions are investigated. Within the HAIC FP7 European project, TAI will implement models related to the ice crystal accretion calculation to the existing ice accumulation prediction program for droplets, namely TAICE. Considered models include heat transfer & phase change model, drag model and impact model. Moreover, trajectory model and Extended Messinger Model require some modifications to be used for ice crystal accretion predictions.

Modern aerospace industry develops assembly process lines for new aircraft which is produced on a single production line while shortening production times by new technologies. Production processes are developed with systems such as lightweight fixtures, reconfigurable tools, automated part positioning, automated scanning countersink control, automated riveting, robotic measurement etc. These systems provide the necessary flexibility for aircraft fuselage and wing assembly projects. Aerospace manufacturers invest in assembly lines in order to increase production rates and meet growing customer demands. Most of the investments are allocated to state-of-the-art robots for drilling and riveting, sealing, coating and painting applications, in addition to material handling, carbon fiber layup and different types of machining operations.