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The presentation provides an overview about the activities of Eurocae Working Group 72 (WG-72) starting with a brief synopsis of the context which suggested why such a committee should be established in 2006. It then goes into further detail about the drivers for the work of the committee, which call for the products to be delivered. It addresses some of the challenges with respect to its users. It points out that one of the lessons the committee learned was importance of the focus on the users, such that the products provide their maximum utility. Hence, the users should better be among the participants to achieve this objective. Other industries have dealt with the subject of Information System (or Cyber-Physical) Security long before this industry was forced to consider it. Consequently there are many industry standards and national or international norms, which may help to develop what is deemed needed for Civil Aviation.

Can you become a visionary or are you born one? How does a visionary capture an opportunity and makes it a successful business? Are engineers more qualified to solve technical problems or run companies? SAE's "The Visionary's Take" addresses these and many other questions, by talking directly with those who have dared to tackle difficult engineering problems, and create real-life products out of their experience. In these short episodes, Sanjiv Singh and Lyle Chamberlain, respectively CEO and Chief Engineer from Near Earth Autonomy, talk about their experience in creating a brand-new company in the UAV world. Founded in 2011, Near Earth Autonomy brought together a group of engineers and roboticists, looking for unconventional solutions to very hard logistics problems, presenting danger to human life. The answers were developed by pushing technology to a higher level, testing quickly and often, and keeping an open mind to alternative ways of framing engineering challenges.

With the increased demand for high volume, cost-effective, fiber-reinforced thermoplastic parts, the lack of high throughput systems has become more pronounced. Thermoforming as a method to generate complex shapes from a flat preform is dependable and fast. In order to use readily available, standard unidirectional impregnated thermoplastic tape in this process, a flat perform must be created prior to the thermoforming step. Formerly, creating the preform by hand layup was a time consuming and therefore costly, step. Fiberforge�?s patented RELAY� technology overcomes the challenges of handling thermoplastic prepreg tape and provides a solution through the automated creation of a flat preform, referred to as a Tailored Blank?. Producing a part for thermoforming with accurate ply orientation and scrap minimization is now as simple as loading a material spool followed by a pressing a start button. Presenter Christina McClard, Fiberforge

Abstract A key problem of the construction of fully electric aircraft is the limited energy density of battery packs. It is generally accepted that this can only be overcome via new, denser battery chemistry together with a further increase in the efficiency of power utilization. One appealing approach for achieving the latter is using laser-assisted filler-based joining technologies, which offers unprecedented flexibility for achieving battery cell connections with the least possible electrical loss. This contribution presents our results on the effect of various experimental and process parameters on the electrical and mechanical properties of the laser-formed bond.

Abstract Improving the energy performance of batteries can increase the reliability of electric aircraft. To achieve this goal, battery management systems (BMS) are required to keep the temperature within the battery pack and cells below the safety limits and make the temperature distribution as even as possible. Batteries have a limited service life as a result of unwanted chemical reactions, physical changes that cause the loss of active materials in the structure, and internal resistance increase during the charging and discharging cycle of the battery. These changes usually affect the electrical performance of batteries. Battery life can be increased only by reducing or preventing unwanted chemical reactions. Lithium-ion (Li-ion) batteries are a suitable option due to their high specific energy and energy density advantages. In this study, the necessity of heat management is emphasized. The discharge tests of the Li-ion battery provided 94.6 Wh under 10C and 90.9 Wh under 1C.

Abstract The range of an aircraft is determined by the amount of energy that its batteries can store. Today, larger batteries are used to increase the range of electric vehicles, although energy efficiency decreases as the weight of the vehicles increases. Among the elements, lithium (Li) is the lightest and has the highest electrochemical potential. Therefore, the use of Li-ion batteries is recommended for hybrid aircraft. In addition, Li-ion batteries are the most common type of battery that is used in portable electronic devices such as smartphones, tablets, and laptops. However, Li-ion batteries may explode due to temperature. Therefore, the thermal analysis of Li-ion batteries was investigated both experimentally and numerically. Li-ion batteries were connected in series (the number is 9). Noboru’s theory of heat generation was discussed in the estimation of energy data.

Abstract The supersession of metallic alloys with lightweight, high-strength composites is popular in the aircraft industry. However, aviation electronic enclosures for large format batteries and high power conversion electronics are still primarily made of aluminum alloys. These aluminum enclosures have attractive properties regrading structural integrity for the heavy internal parts, electromagnetic interference (EMI) suppression, electrical bonding for the internal cells, and/or electronics and failure containment. This paper details a lightweight carbon fiber composite chassis developed at Meggitt Sensing Systems (MSS) Securaplane, with a copper metallic mesh co-cured onto the internal surfaces resulting in a 50% reduction in weight when compared to its aluminum counterpart. In addition to significant weight reduction, it provides equal or improved performance with respect to EMI, structural and flammability performance.

This activity is focused on more electric and all electric type power systems for air vehicles. The scope of which includes source, distribution and user contributions to electrical power quality, failure modes, coordination, system reliabilty and robustness, impacts of being flight critical and the gaps which exist in present standards and guidance documents.

AS 6413 and slash sheets /1 & /2 hold the main information for testing of battery packaging. This document holds further information and expansion of philosophy, clarification etc. surrounding the testing and industry needs.

This SAE Aerospace Information Report is intended to provide advanced methods for wire selecting and sizing in aerospace application as a continuation of AIR6540, Fundamentals in Wire Selection and Sizing for Aerospace Applications. Also, it will provide valuable information for the electrical design engineer to verify the proper wire selection and validate a set of system design requirements which includes meeting environmental and installation constraints.

EPS stability is an essential property that defines EPS ability to provide secure operation under required range of operation scenario. Power system stability is defined as “the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance, with most system variables bounded so that practically the entire system remains intact”. This is applicable for AC and DC systems and has to address steady state conditions, transient conditions as well as high power loads connection / disconnection on the network.

This standard is intended to demonstrate and document the control of the potential hazards from lithium cells or batteries (UN 3090 and 3480) when transported as cargo on aircraft. [still need to identify if we are addressing global (external fire) or local (battery internal failures)] This standard addresses the need to control the hazards which might arise from a failure from an individual cell by containing the hazards within the package. This specific hazards addressed within this standard are: • Uncontrolled fire • Rapid overpressure pulse within compartment

This category specification provides a minimum performance standard that may be used for mitigation means, in addition to the foundation specification (AS6413), to provide external fire thermal threat capability which supports the safe shipment of lithium batteries as cargo on aircraft. This slash sheet provides information and testing to assist or augment the performance of the packaging used for shipping of lithium batteries. If protective equipment and measures are used, the performance of the battery package under the challenge of external heat and fire may be improved and enhanced.  

This category specification provides a minimum performance standard that may be used for mitigation means, in addition to the foundation specification (AS6413), to provide external fire thermal threat capability which supports the safe shipment of lithium batteries as cargo on aircraft. This slash sheet provides information and testing to assist or augment the performance of the packaging used for shipping of lithium batteries. If protective equipment and measures are used, the performance of the battery package under the challenge of external heat and fire may be improved and enhanced.  

The need for developing this standard is driven by the quickly evolving field of electrified propulsion for aircraft. Industry is moving forward in development of a broad range of high voltage primary power systems. There is an immediate need to standardize power quality requirements for design, analysis, verification, and testing for these types of systems.

Technical requirements especially related to the design and construction and the minimum performance requirements (including qualification test conditions) for PM motors and power converters (operated as VFDs) used as the prime mover for more-electric, hybrid-electric, and fully-electric aircraft propulsion systems.

This AIR intends to better document and tabulate electrical load dynamics that influence power source capacity, power quality and stabiltiy.

To determine the end-of-life criteria of electrical insulation materials and components and predict insulation life in high voltage aviation applications

To provide test guidelines, recommendations and referenced standards for insulation materials in a high energy system especially at high voltages (AC, DC and PWM) and at high altitudes, in the purpose of defining/measuring the effects of insulation ageing.

This standard applies to the interconnection of data terminal equipment and numerical control equipment at the tape reader interface. The data terminal would typically be connected to a remote data source/sink such as a computer. This standard defines: This standard is applicable for the interchange of signals when used in conjunction with electronic equipment, each interchange circuit of which has a single return (signal ground) that can be interconnected at the interface point. Figure 1.1, typical installation, shows how this standard should be applied to a typical tape reader interface of numerical control equipment.