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ECOA is an active software architecture research programme conducted by the French Republic and United Kingdom. It is one product of the recent Defence and Security Co-operation Treaty signed between the two nations. This paper provides an overview of the programme goals and progress as well as an introduction to the technology being developed and comparison to related initiatives. The goal of the ECOA programme is to define an open software architecture that enables collaborative development of mission system software. The ECOA programme is needed to reduce development and lifecycle costs of future military air programmes. For this reason the programme has a specific focus on combat-air mission systems but the underlying technology is general purpose, applying to multiple military and civil domains. At present, the programme has defined a concept, delivered a set of initial technical standards and produced a joint demonstrator to validate the technology developed.

Within the aerospace industry there is a growing interest in evaluating and reducing the environmental impacts of products and related risks to business. Consequently, requests from governments, customers, manufacturers, and other interested stakeholders, for environmental information about aerospace products are becoming widespread. Presently, requests are inconsistent and this limits the ability of the aerospace industry to meet the informational needs of various stakeholders and reduce the environmental impacts of their products in a cost-effective manner. Energy consumption is a significant business cost, risk, and a simple proxy value for overall environmental impact. This paper presents the initial research carried out by an academic and industry consortium to develop standardised methods for calculating and reporting the embodied manufacturing energy content of aerospace products.

A structural damage detection system has been used to sense the propagation of cracks in a metallic flight test specimen on board a Hawk jet trainer. The work has demonstrated that the growth of structural cracks can be successfully and automatically detected on board a fast jet while flying unrestricted flight profiles. The experiment was part of a European collaborative defense program designed to demonstrate a number of diverse structural health monitoring technologies during flight in a military jet environment. This paper focuses on the performance of an acoustic emission detection system that was able to detect the growth of cracks in an alloy cantilever specimen bolted to a structural bulkhead in a pod suspended beneath the aircraft's left hand wing.

SCONES (Stress CONcentration Expert System) software is used to predict stress concentrations. When dimensions and loads are modified it instantaneously updates the display, making the system easy to use. SCONES contains validated and extended data from various sources, including complex interacting features which augments SCONES role. However, the natural progression is to extend the research to the interaction of processes including, for example, surface processes like anodising. These process interactions will dovetail into, and enhance features within the strain life factors. This paper will describe new work which will extend current knowledge in feature interactions and strain life factors and will improve SCONES versatility.

Pilots in fighter aircraft can be subjected to high temperatures during ground operating phases in hot climate conditions, especially if APU mode is not available. A Cooling Generation System (CGS) used with a protective thermal garment for fighter aircraft pilots has been developed that allows cooling of the pilot in the cockpit. The unit is designed to operate under worst case conditions and requires only that the pilot plugs in upon entering the cockpit. A liquid circulates inside the garment that covers the pilot’s torso, arms and head (area under the helmet). The temperatures are defined to guarantee the user’s comfort. The pilot can adjust the power delivered by the CGS, i.e. the temperature of the circulating fluid, up to a maximum cooling capacity of 400 W. The CGS design is based on a small variable speed compressor with a brushless motor, which is the outcome of a dedicated development, and a custom-made evaporator and condenser for maximum efficiency and minimum volume.

Electrification of aircraft is on track to be a future key design principal due to the increasing pressure on the aviation industry to significantly reduce harmful emissions by 2050 and the increased use of electrical equipment. This has led to an increased focus on the research and development of alternative power sources for aircraft, including fuel cells. These alternative power sources could either be used to provide propulsive power or as an Auxiliary Power Unit (APU). Previous studies have considered isolated design cases where a fuel cell system was tailored for their specific application. To accommodate for the large variation between aircraft, this study covers the design of an empirical model, which will be used to size a fuel cell system for any given aircraft based on basic design parameters. The model was constructed utilising aircraft categorisation, fuel cell sizing and balance of plant sub-models.

Model Based Safety techniques have been developed for a number of years, though the models have not been customised to help address the safety considerations/ actions at each refinement level. The work performed in the MISSA Project looked at defining the content of “safety models” for each of the refinement levels. A modelling approach has been defined that provides support for the initial functional hazard analysis, then for the systems architectural definition level and finally for the systems implementation level. The Aircraft functional model is used to apportion qualitative and quantitative requirements, the systems architectural level is used to perform a preliminary systems safety analysis to demonstrate that a system architecture can satisfy qualitative and quantitative requirements.

Impact events on composite structures that may cause damage can be readily detected and located using sensors that respond to the resulting impact stress waves as they propagate. This capability can be used as an alert to maintainers or operators who use the structures that an incident has occurred. However, for this capability to be truly useful it must include the capacity to determine automatically if the impact has caused damage. This will avoid the situation where a follow up inspection of the impact site reveals that no damage has been caused (no-fault found). This paper reports results from impact tests on glass and carbon composite, structural test specimens in which impact sensor data has been processed to reveal clear features that allow discrimination between damaging and non-damaging impacts.

An essential part of the SHM validation effort is to check the presence and adequacy of the methods required to validate the correct functionality of each SHM task, which can be targeted at detecting structural faults. The ultimate proof of the correct functionality is validation evidence, e.g. crack detection evidence, observed during the operation of the aircraft. However, the occurrences of structural faults such as cracks are infrequent, and hence, years of flight tests might be required to collect validation evidence; small numbers of flights would be only sufficient to prove the system's “fitness for flight” and would be insufficient to prove “fitness for purpose”. Validation evidence can be collected during laboratory tests by inducing faults in structural specimens and examining the SHM detection capability.

UAS (Unmanned aircraft system), widely known to the general public as drones, are comprised of two major system elements: an Unmanned Aircraft (UA) and a Ground Control Station (GCS). UAS have a high mishap rate when compared to manned aircraft. This high mishap rate is one of several barriers to the acceptance of UAS for more widespread usage. Better awareness of the UA real time as well as long term health situation may allow timely condition based maintenance. Vehicle health and usage are two parts of the same solution to improve vehicle safety and lifecycle costs. These can be worked on through the use of two related aircraft management methods, these are: IVHM (Integrated Vehicle Health Management) which combines diagnosis and prognosis methods to help manage aircraft health and maintenance, and FOQA (Flight Operations Quality Assurance) systems which are mainly used to assist in pilot skill quality assurance.

Determination of the so-called stress concentration factor (Kt) is essential for the correct design of components subject to fatigue-inducing loading. The paper introduces methods and software for stress concentration analysis and techniques for structural design optimization based on the redistribution of material to balance stress concentration efforts.

In the frame of the development of the European EVA Suit, a complete trade-off was conducted to select the lower torso architecture. This study, performed under an ESA contract, included a formal trade-off dealing with all cost and programmatic impacts together with a technical assessment based on man rated underwater evaluations and analysis. The candidate architectures were: the European baseline including 2 hip and 2 thigh bearings, the Russian like soft ORLAN-DMA, a soft lower torso including 2 thigh bearings and another soft one including 2 calf bearings. The idea was to compare the different design performances without having necessarily developed the 4 pressurized lower torsos and then also to gain experience on predicting methods for such ergonomic/kinematic studies. The trade-off was based on the manned underwater evaluation of ergonomical suit simulators (wet suit concept), supported by the 1-g pressurized evaluation of the Russian ORLAN-DMA and CAD-CAM kinematic analysis.

The Flexible Assembly Cell for Aeronautical Industry (FACAI) is described. The cell was developed in order to take advantage of the benefit of hard automation while retaining the flexibility of the manual assembly system it replaces. A description of both the generic equipment, selected to be non-specific to both the process and the assemblies intended to be built, is provided. In addition, all specific hardware, including end-effectors and fastener distribution systems are described, along with the rationale for their choice. The reasons for the modular design are explained. The means by which the flexibility goal was achieved are outlined. The demonstrated ability of the cell to install a wide range of fasteners (solid rivets, lockbolts, Hilocks) without the need for manual reconfiguration is detailed. The means by which both the quality and safety goals were attained are explained.

This paper synthesizes the shoulder joint development activities performed in the frame of the European EVA Space Suit System (ESSS) programme. The shoulder joint belongs to the anthropomorphic enclosure encompassing the crewmember, protecting him against space environment while ensuring him adequate mobility, dexterity and visibility. A conceptual trade-off selected two candidates likely to fulfil the stringent shoulder joint requirements: an all-soft joint and a hybrid “rolling convolute”. Representative pressurized breadboards were designed, manufactured and tested. The tests addressed both intrinsic performance, via torque/flexion hysteresis curves and ergonomic characteristics via a “man in the loop” evaluation, involving a suit demonstrator. Tests results completed the trade-off, thus enabling the industrial team to formulate recommendations and propose further development studies.

A Distributed Engine Control Working Group (DECWG) consisting of the Department of Defense (DoD), the National Aeronautics and Space Administration (NASA)- Glenn Research Center (GRC) and industry has been formed to examine the current and future requirements of propulsion engine systems. The scope of this study will include an assessment of the paradigm shift from centralized engine control architecture to an architecture based on distributed control utilizing open system standards. Included will be a description of the work begun in the 1990's, which continues today, followed by the identification of the remaining technical challenges which present barriers to on-engine distributed control.

Quality has been the illustrious word of the 80s and 90s as we speak organizations are chasing quality problems through the engineering teams and into production. Taskforces of workers in white coats are being sent on to the production line to furiously check components, monitoring process capability in an attempt to improve product quality. Unfortunately it's only after several years of production that the first “real” data gets back to the engineering teams, when it is often too late to remove the causes of these quality problems. The organization is left kicking itself over the same old catch twenty-two situations, “If only the team knew this process data before they decided to engineer it like that!”

Bleeding in engines is essential to mitigate the unmatched air massflow between low and High Pressure (HP) compressors at low speed settings, thus avoiding unstable operation due to surge and phenomena. However, by emerging the More Electric Aircraft (MEA) the engine is equipped with electrical machines on both high and Low Pressure (LP) spools which enables transfer of power electrically from one spool to another and hence provides the opportunity to operate engine core components closer to their optimum design point at off-design conditions. At lower power setting of the engine, HPC speed can be increased by taking power from LP shaft and feeding it to HP shaft which can lead to the removal of the bleeding system which in turn reduces weight and fuel consumption and help to overcome engine instability issues. Fuel consumption can be decreased by decreasing inconsistent thrust with the aircraft mission for flight and ground idle settings.

Avcorp Industries Inc. recognized the need to reduce assembly labor costs in order to stay competitive with global competition. After two years of research and investigation it was determined that a joint project with Dassault Aviation provided the most viable solution. The key elements of the technology developed by Dassault were its high flexibility and rapid payback of capital investment. This paper describes the system and the application. The structure’s design and robotic system design were performed in parallel. A number of design challenges had to be overcome. Many of these issues encountered were common to any automated assembly application. By covering these challenges Avcorp was able to introduce automated assembly at a level that had typically been previously attained exclusively by much larger enterprises. The robotic system consists of two anthropomorphic robots, which work both individually and in tandem.

It is generally accepted that the development of hardware and software for safety critical systems follow their own lifecycles as defined by standards such as RTCA DO254 and RTCA DO178C. What is less clear is what should be done to ensure the system safety objectives are met when the software is installed in the electronic hardware. This paper seeks to discuss the activities that may be undertaken do demonstrate not only that the integration of the software and hardware “work” together, but they do so in a manner that meets the safety objectives in line with the guidelines described in SAE ARP4754A. According to ARP4754A, hardware and software are different “items” developed according to their own requirements and standards, when two or more items are brought together, they are a system, which may be part of a larger system. Therefore system level considerations need to be applied from the beginning of the development program addressing the system safety and certification activities.

A lot of studies have been carried out over the last decades on SLD ice accretion challenges. Many of them referred to SLD physics modelling such as break-up, splashing, bouncing, etc… and relied on numerous physics experiments. Different models have been developed in Europe and North-America and have been implemented in several numerical tools, widely in 2D but more and more in 3D. As these tools are intended to be used increasingly among the community, deficiencies have to be deeper investigated. This paper provides some highlights on specific needs linked to SLD impingement and ice accretion, especially for 3D high fidelity computations. Regarding the results, deficiencies on the numerical side and on experimental needs will be highlighted in order to feed brainstorming for ongoing SLD projects such as in European Union H2020 ICE-GENESIS.