Although aerospace traditionally has always had a multidisciplinary approach to engineering and design, the increasing complexity of aircraft and spacecraft and the rapid digitization within the aerospace industry has led to a large number of related engineering and scientific disciplines such as electrical engineers, computer scientist to work much more directly within the aerospace domain than before. Next to that there is a shortage of highly trained engineers worldwide to meet demand. As a result, there is a clear need to provide basic knowledge to non-aerospace engineers working in the field and to motivate and attract more people to engineering and aerospace in particular. This paper details how the creation of a Massive Open Online Course (MOOC) at an introductory level in Aerospace Structures and Materials provides an efficient and fit-for-purpose tool to achieve both aims. The paper will discuss the course design, the course set up, the course evaluation and how the course fits within the online learning philosophy of Delft University of Technology. It will use learning analytics to analyze our learners and their needs.

This paper presents two major elements of a course redesign with the aim to strengthen the connection between engineering design and engineering analysis. The course, Aircraft Structural Design and Analysis, had previously been delivered with a heavy focus on mathematical analysis and solving complex problems. It was observed, however, that in later design projects within the curriculum, students were unable to apply these skills in a less constrained design context. To combat this, two course elements were introduced. The first element was a design tutorial session that ran in parallel with the course and interfaced with real design activities being carried out within the AeroDelft Dream Team at Delft University of Technology. This session attempted to have students apply the skills they had learned in class to a less constrained design problem with more freedom than traditional practice problems, focusing on design thinking rather than reproducing an expected answer. The second element was a design-based final exam, where all of the questions within the exam were interconnected by a single design context. The first iteration of these design elements, including lessons learned and an analysis on their impact on student success, will be presented within this paper.

A challenge in developing an in-depth understanding of the crack growth resistance of ALM materials is the fact that mechanical properties of additive manufactured materials have been shown to be both process and part-geometry dependent. Up to now, no studies have investigated the influence of off-axis (beyond the three orthogonal build orientations) orientations on the fatigue crack growth behaviour of selective laser melted Ti-6Al-4V. Furthermore, the widespread use of compact tension specimens for investigating the material behaviour generates data more suitable for plane-strain conditions, rather than the plane-stress state which is more applicable to many lightweight aerospace structures. To address this gap in knowledge, a comprehensive study was carried out to investigate the influence of off-axis build direction inthin SLM Ti-6Al-4V plates, with a focus on the influence of microstructure anisotropy on the fatigue crack growth behaviour. It was found that although an anisotropic grain structure is visible on the specimens, it had no discernible influence on the crack growth resistance when the specimen had undergone a stress relieving heat treatment.

Most universities have taught on-campus courses for decades and although many have also provided for professional (and life-long) learners by means of seminars and short courses taught on-site on set topics, few universities had a set program to offer professional learners dedicated courses based on original on-campus courses.

After the widely-publicized success of the Massive Open Online Course (MOOC) on Artificial Intelligence by Thrun and Nordvic from Stanford in 2011 with over 160,000 enrolled, the endless possibilities of online learning started to reach the world of STEM education. At the Faculty of Aerospace Engineering, the largest aerospace faculty in Western Europe with an enrollment of almost 3,000 BSc, MSc and PhD students, of Delft University of Technology in the Netherlands started to develop its own array of online courses ranging from MOOC to blended campus courses and paid on-line MSc courses (Groot-Kormelink et al., 2013 and Saunders-Smits et al, 2014).

Initially, the paid online MSc courses were intended for the working professionals as well as for our own on-campus students, but experience quickly showed that the needs, interest and priorities of a working professional are very different than that of an on-campus learner. A need arose for a new type of online courses: the so-called ProfEd – Professional Education, aimed at working professionals in the field, teaching at academic level, taking into account the specifics of these learners.

This paper will outline how two Aerospace Engineering MSc courses were transformed into two successful ProfEd courses run via the online platform of TU Delft (onlinelearning.tudelft.nl). The courses highlighted as case studies are:

• Smart Structures, a course on the use of smart structures in aerospace allowing the learner to get introduced to the field and apply their new found knowledge to real-world aerospace examples and beyond,
• Air Safety Investigation, which aims to decipher the myth behind air safety investigation with an aim to educate anyone who is involved in the chain of air safety incidents and accidents with the way of thinking and working of an air safety investigator.

Composite mechanical characteristics can be heavily influenced by impact damages; however, this influence can be reduced by choosing a correct stacking sequence and constituents materials. In this paper, the influence of placing a metal layer within the stacking sequence of a carbon/epoxy laminate on impact resistance was studied. Impacts were simulated by means of Quasi Static Indentation tests.

Today, the application of adhesive bonding technology for primary aerospace structures is limited due to the certification regulations. State of the art is the widely used “chicken rivet” as crack arrestor which is limiting the benefits of bonding technology, particularly in composite bonded joints.

In this paper results from fatigue testing of novel design approaches for damage tolerant high load transfer (HLT) joints as e.g. Panel Joints or large bonded repairs will be discussed for CFRP and for Fiber Matel Laminates´(FML) adherents.

Results from fatigue testing with Wide Single Lap shear (WSLS) specimen will be presented for different configurations to proof the crack stopping behavior of sate of the art fasteners as reference crack arrestor concept.

Large classroom sizes are a reality university educators need to contend with, particularly in the first year of a given cohort within a degree programme. Activating and engaging students in these large classroom environments present numerous sets of challenges. These challenges are exacerbated by student learning development needs in the early stages of the degree programme. In their first year, students are still adapting to a new learning environment and are developing new study skills and practices. Early success and failure in courses will shape intrinsic and extrinsic factors that will motivate the student in the remainder of their degree. Thus the perceived challenge of activating large classrooms early in a degree programme goes beyond simple engagement; beneath the core learning objectives of the course are implicit learning objective about developing effective motivation and study skills.

This paper examines the efforts to reorganize a first year Mechanics of Materials course taught in the Bachelor of Engineering Programme within the Faculty of Aerospace Engineering at Delft University of Technology University to address this need using a Blended Learning approach.

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Currently, Strain Energy Release Rate (SERR), or a function of it (Gmax,  DG among others) is used to predict Fatigue Disbond Growth (FDG). However, Fig 1.a shows that the use of such variable does not completely describe FDG at Mixed-Mode conditions. Pascoe et al [1] proposed a new approach to improve disbond phenomenon understanding. This manuscript expands the theory developed in [1], which focus on the stress ratio effect, for FDG under mixed-mode conditions. Figure 1.b presents a preview of the results. This figure shows clearly the collapse of all FDG data into a single trend. Despite the fact that Ucyc can only be calculate a posteriori, the use of cyclic strain energy can contribute for the Mixed-Mode FDG understanding and be later developed into a predictive model.

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In this study, mode II fatigue crack growth utilizing Central Cut Plies (CCP) specimens is considered, in order to assess the durability of bonded composite repairs. Fatigue tests were performed with unidirectional carbon-epoxy specimens and adhesive film co-cured. A back-face strain technique was used to obtain strain data with a fiber optics distributed sensing system based on Rayleigh Backscattering. Crack growth rates were obtained from the strain profiles and the results show a good correlation with other measurement techniques. The technique also indicated an unequal crack growth behavior as observed in the ultrasonic inspection. As a consequence, it was verified that the common CCP geometry used for static tests is not ideal for fatigue tests and thus, this type of specimen requires further improvement for fatigue assessment of bonded composite repairs.

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