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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.

“Spotlight on Design: Insight” features an in-depth look at the latest technology breakthroughs impacting mobility. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. As global concerns about the negative consequences of greenhouse gases on the environment increase, regulatory agencies around the world are taking serious steps to address the issue of tailpipe emissions In the episode “Fuel Efficiency: Fuel Economy Testing” (12:05), engineers at the EPA’s National Vehicle and Fuel Emissions Laboratory demonstrate how different vehicles are tested for emissions, and AVL’s technical team shows how accurate tailpipe emissions can be measured and reported.

This SAE Aerospace Information Report (AIR) describes procedures, required continuous sampling conditions, and instrumentation for the measurement of non-volatile particle number and mass concentrations from the exhaust of aircraft gas turbine engines. Procedures are included to calculate sampling loss performance. This AIR is not intended for in-flight testing, nor does it apply to engine operating in the afterburning mode.

This Aerospace Information Report (AIR) is a historical technical record describing procedures, required continuous sampling conditions, and instrumentation for the measurement of non-volatile particle number and mass concentrations from the exhaust of aircraft gas turbine engines. Procedures are included to calculate sampling loss performance. This AIR is not intended for in-flight testing, nor does it apply to engine operating in the afterburning mode. This Aerospace Information Report is a historical technical record of the initial document detailing the measurement of non-volatile particle emissions at the exit plane of aircraft gas turbine engines. This methodology was adopted by ICAO into Annex 16 Vol II and updated into Aerospace Recommended Practice ARP6320. Future updates of this document may include explanations of the reasoning and assumptions used to develop this measurement methodology.

Abstract Constant area section length downstream to the fuel injection point is a crucial dimension of scramjet duct geometry. It has a major contribution in creating the maximum effective pressure inside the combustor that is required for propulsion. The length is limited by the thermal choking phenomenon, which occurs when heat is added in a flow through constant area duct. As per theory, to avoid thermal choking the constant area section length depends upon the inlet conditions and the rate of heat addition. The complexity related to mixing and combustion process inside the supersonic stream makes it difficult to predict the rate of heat addition and in turn the length. Recent efforts of simulating the reacting flow inside scramjet combustors are encouraging and can be useful in this regard. The presented work attempts to use simulation results of scramjet combustion for predicting the constant area section length for a typical scramjet combustor.

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 Jet engine hot parts (e.g., jet nozzle) are a crucial source of aircraft’s infrared (IR) signature from the rearview, in 1.9-2.9 μm and 3-5 μm bands. The exhaust nozzle design used in a jet aircraft affects its performance and IR signature (which is also affected just by performance) from the engine layout. For supersonic aircraft (typically for M ∞ > 1.5), a converging-diverging (C-D) nozzle is preferred over a convergent nozzle for optimum performance. The diverging section of the C-D nozzle has a full range of visibility from the rearview; hence, it was not considered a prudent choice for low IR observability. This theoretical study compares the IR signature of the C-D nozzle with that of the convergent nozzle from the rearview in 1.9-2.9 μm and 3-5 μm bands for the same thrust.

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 Aerospace Information Report (AIR) is a historical technical record describing procedures, required continuous sampling conditions, and instrumentation for the measurement of non-volatile particle number and mass concentrations from the exhaust of aircraft gas turbine engines. Procedures are included to calculate sampling loss performance. This AIR is not intended for in-flight testing, nor does it apply to engine operating in the afterburning mode.

This Aerospace Information Report is a historical technical record of the initial document detailing the measurement of non-volatile particle emissions at the exit plane of aircraft gas turbine engines. This methodology was adopted by ICAO into Annex 16 Vol II and updated into Aerospace Recommended Practice ARP6320.

Future updates of this document may include explanations of the reasoning and assumptions used to develop this measurement methodology.

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.

To inform users on proper use, procedures and common errors when using electronic compensation for tooling on horizontal and vertical balancing machines

Provide guidance on how balance machine vector data is captured and reported. Provide an understanding of how to transform balance machine vector data to alternate locations. Provide guidance on how vector imbalances may be used to evaluate and diagnose balance process performance.

Set forth dimensions and specifications for Nickel Alloy N07718 100 deg csk 0.114” to 0.3750” diameter screws with AS6305 recess.

This document establishes process parameters for gas turbine rotor balancing. Adherence to the recommendations made herein will facilitate attainment of the usually high degree of accuracy and precision required for jet engine rotor balance.

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 scope of these standards will relate to single-axis moment scales only. Topics covered include dimensional characteristics of single-axis moment scale interfaces, general tooling requirements, scale and tooling accuracy, and display instrument accuracy requirements. Additionally, general guidelines for qualification of equipment and tooling are included, as are general requirements for single-axis blade distribution software.