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Engine oil systems drive and de-aerate air-oil solutions in a two-phase flow to provide an appropriate amount of oil lubrication and cooling. especially in aero-engine and starter-generator component and system. The oil lubrication systems combine three important functions of the Main Oil Pump (MOP) for lubrication and scavenging: the de-aeration and de-oiling of the air-oil mixture generated in the bearing and gearbox sumps and pumping the oil towards the tank. These are critical functions for the aero-engine and starter-generator. An aero-engine lubrication system along with an integrated pump and separation of gas-liquid mixture has been developed and characterized experimentally to increase Collins Aerospace Engine and Control Systems research and development productivity. This system has also improved engine and starter-generator reliability and system performance.

Aircraft systems have a stringent requirement governed by the certifying authorities demanding that the system and components are qualified for all the applicable requirements. Conducting qualification tests on all the components in a system for all operational requirements, environmental loads, and the loads for uncertainties such as limit and ultimate cases would consume a significant time in the product design cycle. With improved computational power and with validated higher fidelity models, structural analysis is proving to be a way forward in reducing the product design cycle time. This paper discusses about the structural analysis driven qualification test definition aligning with modes of compliances defined by CS25 / FAR 25 with an objective to minimize and simplify the tests carried out as a step towards certification by analysis.

A typical linear hydraulic actuator would have clearances between the mating components such as Piston-Cylinder arrangement for achieving the functional requirements. It is observed from the vibration tests that the natural frequencies and the responses vary significantly with the excitation levels in these actuators. With increase in the excitation levels natural frequency of the actuators increases, and the damping ratio reduces significantly indicating a nonlinear behavior of the system. Also due to these clearances, jump phenomena and cubic stiffness nonlinearity are identified on the typical hydraulic actuators. The characterization of the clearances and its impact on the vibratory responses is discussed in this paper. Clearances at two interface locations for a typical hydraulic actuator were identified and a Design of Experiments (DOEs) was formulated with different levels of clearances.

This paper provides an overview of the state-of-art multiscale “Icing Simulation Framework” capability developed at Raytheon Technologies Research Center. Specifically, the application of this framework to simulate droplet runback and runback icing will be presented. In summary, this high-fidelity framework tracks the physical mechanisms associated with droplet dynamics, ice nucleation, growth and interaction with the environment (e.g. adhesion, crystal growth, evaporation, sublimation, etc.) across all relevant scales (including nucleation at <10-7m to ~10-6m of coating/environment interaction to 10-2m of the component) which allows a rigorous investigation of how different environmental (e.g. LWC, MVD, pressure, velocity and temperature) and substrate (e.g. coating molecular and macroscopic specifications) characteristics affect the icing behavior.

The Collins Aerospace Optical Ice Detector is a short-range polarimetric cloud lidar designed to detect and discriminate among all types of icing conditions with the use of a single sensor. Recent flight tests of the Optical Ice Detector (OID) aboard a fully instrumented atmospheric research aircraft have allowed comparisons of measurements made by the OID with those of standard cloud research probes. The tests included some icing conditions appropriate to the most recent updates to the icing regulations. Cloud detection, discrimination of mixed phase, and quantification of cloud liquid water content for a cloud within the realm of Appendix C were all demonstrated. The duration of the tests (eight hours total) has allowed the compilation of data from the OID and cloud probes for a more comprehensive comparison. The OID measurements and those of the research probes agree favorably given the uncertainties inherent in these instruments.

The purpose of this paper to is to review the methodology applied by Collins Aerospace to develop, test and qualify a more robust surface ply rubber compound that has demonstrable improvements in durability and performance at sub-freezing temperatures. Using in-service products as a reference, pneumatic deicers in use on regional turboprop applications were selected as a basis for operational characteristics and observed failure modes. Custom test campaigns were developed by Collins to comparatively evaluate key characteristics of the surface ply material including low temperature elasticity, erosion durability, and fluid susceptibility. Collins’ proprietary engineered rubber formulations were individually evaluated and built into fully functional test deicers for component level testing to DO-160G environmental exposure, comparative ice shed performance in Collins’ Icing Wind Tunnel and erosion in Collins’ Rain Erosion Silo.

The aerospace ecosystem is a complex system of systems comprising of many stakeholders in exchanging technical, design, development, certification, operational, and maintenance data across the different lifecycle stages of an aircraft from concept, engineering, manufacturing, operations, and maintenance to its disposal. Many standards have been developed to standardize and improve the effectiveness, efficiency, and security of the data transfer processes in the aerospace ecosystem. There are still challenges in data transfer due to the lack of standards in certain areas and lack of awareness and implementation of some standards. G-31 standards committee of SAE International has conducted a study on the available digital data standards in aircraft asset life cycle to understand the current and future landscapes of the needed digital data standards and identify gaps. This technical paper presents the study conducted by the G-31 technical committee.

In the aerospace industry, competition is high and the need to ensure safety and security while managing costs is paramount. Furthermore, stakeholders—who gain the most by working together—do not necessarily trust each other. Now, mix that with changing enterprise technologies, management of historical records, and customized legacy systems. This issue touches all aspects of the aerospace industry, from frequent flyer miles to aircraft maintenance and drives tremendous inefficiency and cost. Technology that augments, rather than replaces, is needed to transform these complex systems into efficient, digital processes. Blockchain technology offers collaborative opportunities for solving some of the data problems that have long challenged the industry. This SAE EDGE™ Research Report by Rhonda D. Walthall examines how blockchain technology could impact the aerospace industry and addresses some of the unsettled concerns surrounding its implementation.

As the complexity of systems expands with increasing emphasis for digital transformation, the aerospace industry is generating big data to meet customer requirements. The ability to that data to solve challenging problems is limited by many factors, including the capabilities of current classical computing systems. Impact of Quantum Computing in Aerospace discusses how quantum computing systems offer (possibly quadratic to exponentially) greater computational power over classical computers. The power of quantum computing is tremendous and has many potential impacts on the aerospace industry; however, there are also many unsettled topics surrounding the future of the technology. Click here to access the full SAE EDGETM Research Report portfolio.

The FE analysis of complex systems with lot of intricate features and fillets modeled in detail would result in a huge FE model size making it difficult to handle. Therefore, to reduce the computation time, defeaturing of such regions are carried out as a common practice and these critical stress concentration regions can be studied using submodeling approach later based on response superimposed from the global models. This method is widely practiced and is quite easy to implement for static and harmonic analysis problems. However, there is no well documented methodology exists for submodeling in the random vibration environment. In case of Random vibration analysis, the cut boundary displacements from Power Spectral Density (PSD) analysis would result in unrealistic stresses.

The aircraft asset life cycle processes are rapidly being digitalized. Many novel technologies enabled processes of recording these electronic transactions are being emerged. One such technology for recording electronic transactions securely is Blockchain, defined as distributed ledger technologies which includes enterprise blockchain. Blockchain is not widely used in the aerospace industry due to lack of technical understanding and questions about its benefits. Assessment and establishment of business case for implementing blockchain based solution is needed. The aerospace industry is very conservative when it comes to technology adoption and hence it is difficult to change legacy processes. Additionally, the industry is very fragmented. The technology is advancing at a faster rate and applies across geographies under various regulatory oversight which makes blockchain based solution implementation challenging.

Innovative carbon nanotube (CNT) electrothermal heating technology for ice protection systems is one of the alternatives under development that shall contribute to more efficient and sustainable aircraft. CNT heater technology allows for more rapid heat up rates over legacy metallic electrothermal heaters that utilize resistance wires or metallic foils. This more rapid heat up rate can lead to more energy efficient electrothermal ice protection system designs and is being studied to determine how much the rapid heat up properties of CNT can lead to a minimization of residual ice build-up aft of the heated area. Due to the inherent redundancy of CNT material used, leads to a very robust and damage tolerant heating element. To mature this technology to prepare to implement CNT on an in-service aircraft platform, a multi-staged flight testing effort to prove out the technology on an actual aircraft and in a relevant environment is mandatory.

Avionics systems are currently undergoing a transition from single core processor architectures to multi-core processor architectures. This transition enables significant advantages in reduction in size, weight, power (SWaP) and cost. However, avionics hardware and software certification policies and guidance are evolving as research and experience is gained with multi-core processor architectures. The unique challenges of using multi-core processors in certified avionics will be discussed. The requirements for a virtualization platform supporting multiple real-time operating system (RTOS) partitions on a multi-core processor used in safety-critical avionics systems are defined, including the ability to support multiple design assurance levels (DAL) on multiple cores, fault isolation and containment, static configuration as per ARINC 653, role-based development as per DO-297, and robust partitioning to reduce cost of incremental certification.