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Thin barium titanate (BT) film is being developed for use in microelectronics, electromechanical and optoelectronic applications. For this study rolled thin BaTiO3 film capacitors were fabricated using RF sputtering techniques. Capacitor grade aluminum foil was used as the bottom electrode. The top electrode was sputtered aluminum film, which was used for quick measurement purposes. The as-deposited ceramic film on aluminum foil was very flexible at room temperature and could be easily rolled. The foil was masked to preserve side electrodes. The typical dissipation factors (DF) of these BT film capacitors were in the range of 0.002 to 0.005. A low dissipation factor is extremely important for pulsed power or high power filtering applications. These BT film capacitors had a parallel resistance of 15 to 20 mega-ohm. With the thickness of the film being 8,000 Å, the average dielectric constant was calculated to be 25. The insulation resistance was about 138 giga-ohm.

Currently, aerospace and automotive industries are developing complexand/or highly integrated systems, whose services require greater confidence to meet a set of specifications that are increasingly demanding, such as successfully operating a communications satellite, a commercial airplane, an automatic automobile, and so on. To meet these requirements and expectations, there is a growing need for fault treatment, up to predict faults and monitor the health of the components, equipment, subsystems or systems used. In the last decades, the approaches of 1) Fault Prevention, 2) Fault Detection/Tolerance and 3) Fault Detection/Correction have been widely studied and explored.

Unmanned Aerial Vehicles (UAVs) are becoming an effective way to serve humanitarian relief efforts during environmental disasters. The process of designing such UAVs poses challenges in optimizing design variables such as maneuverability, payload capacity and maximizing endurance because the designing of a BWB takes into account the interdependency between the stability and aerodynamic performance. The Blended Wing Body is an unconventional aircraft configuration which offers enhanced performance over conventional UAVs. In this study the designing of a BWB is investigated with an aim to achieve structurally sound and aerodynamically stable configuration. The design has been done by taking into consideration the side and top view airfoil for fuselage, because fuselage is a major lift generating portion in the UAV. For designing the control surfaces, the two major requirements for a controlled and safe flight of a UAV are its stability and maneuverability.

On-board, tactical airborne sensor systems perform functions such as target acquisition, track, designation, identification, recognition, threat warning, threat count, missile launch detection and ground mapping in support of situation awareness, self-defense, navigation, target attack, weapon support and reconnaissance. Next generation tactical aircraft in development want those functions performed by sensor suits which exploit modular avionics concepts; exhibit low signature and enhanced stealthiness; have increased availability through increased functional redundancy; and are easy and less costly to maintain. Integrated IR sensors incorporating modular avionics concepts can satisfy those needs. Current IR systems for airborne tactical applications are packaged in either aftermarket pod mounted configurations or in chin mounted protuberances.

This paper introduces a data driven model for predicting airport arrival capacity with 2-8 hour look-ahead forecast data. The model is suitable for air traffic flow management by explicitly investigating the impact of convective weather on airport arrival meter fix throughput. Estimation of the arrival airport capacity under arrival meter fix flow constraints due to severe weather is an important part of Air Traffic Management (ATM). Airport arrival capacity can be reduced if one or more airport arrival meter fixes are partially or completely blocked by convective weather. When the predicted airport arrival demands exceed the predicted available airport’s arrival capacity for a sustained period, Ground Delay Program (GDP) operations will be triggered by ATM system.

The aircraft components' lifetime is a key decision–making metric for the performance of safety–critical items. The piece–part degradation and age–related changes are critical from the perspective of design and continued airworthiness. The most obvious issue during design development is to establish the need for planned replacement for components that are known to have a limited life. During investigation of an airworthiness issue, it is necessary to determine if the anomaly is time–dependent. If it is, then the anticipated failure probability as a function of time must be estimated such that a decision regarding corrective action can be made. For both cases, an analysis must be performed to determine if and when planned replacement is necessary. Because unanticipated retrofits are costly and difficult, credible and accurate lifetime prediction is essential.

This paper presents the findings of the trade study to evaluate carbon dioxide (CO2) sensing technologies for the Constellation (Cx) space suit life support system for surface exploration. The trade study found that non-dispersive infrared absorption (NDIR) is the most appropriate high Technology Readiness Level (TRL) technology for the CO2 sensor for the Cx space suit. The maturity of the technology is high, as it is the basis for the CO2 sensor in the Extravehicular Mobility Unit (EMU). The study further determined that while there is a range of commercial sensors available, the Cx CO2 sensor should be a new design. Specifically, there are light sources (e.g., infrared light emitting diodes) and detectors (e.g., cooled detectors) that are not in typical commercial sensors due to cost. These advanced technology components offer significant advantages in performance (weight, volume, power, accuracy) to be implemented in the new sensor.

The safety of commercial aviation industry has come under extensive scrutiny and how the system safety process is applied. One specific system safety regulation concerns how unsafe system operating conditions are meeting regulatory requirements. Minimal regulatory guidance was available on this topic and an industry committee (American Society for Testing of Materials) decided to provide a consensus standard with input from a cross-section of airplane manufacturers, suppliers, and regulatory authorities on what is meant by an unsafe system operating condition and how compliance can be shown to the regulation(s). The committee determined that an unsafe system operating condition is when a failure condition severity increases (to hazardous or catastrophic) due to crewmember(s) inaction. For example, if a hazard has occurred it is possible the severity can increase to an unacceptable level as the crewmember(s) are not aware of the hazard.

Abstract : In any human space flight program, safety of the crew is of utmost priority. In case of exigency during atmospheric flight, the crew is safely and quickly rescued from the launch vehicle using Crew escape system. Crew escape system is a crucial part of the Human Space flight vehicle which carries the crew module away from the ascending launch vehicle by firing its rocket motors (Pitch Motor (PM), Low altitude Escape Motor (LEM) and High altitude Escape Motor (HEM)). The structural loads experienced by the crew escape system during the mission abort are severe as the propulsive forces, aerodynamic forces and inertial forces on the vehicle are significantly high. Since the mission abort can occur at anytime during the ascent phase of the launch vehicle, trajectory profiles are generated for abort at every one second interval of ascent flight time considering several combinations of dispersions on various propulsive parameters of abort motors and aero parameters.

Thermo-mechanical fatigue and natural aging due to environmental conditions are difficult to simulate in an actual test with the advanced fiber-reinforced composites, where their fatigue and aging behavior is little understood. Predictive modeling of these processes is challenging. Thermal cyclic tests take a prohibitively long time, although the strain rate effect can be scaled well for accelerating the mechanical stress cycles. Glass fabric composites have important applications in aircraft and spacecraft structures including microwave transparent structures, impact-resistant parts of wing, fuselage deck and many other load bearing structures. Often additional additively manufactured features and coating on glass fabric composites are employed for thermal and anti-corrosion insulations. In this paper we employ a thermo-mechanical fatigue model based accelerated fatigue test and life prediction under hot to cold cycles.

In today's industrial sphere, machines are the key supporting various sectors and their operations. Over time, due to extensive usage, these machines undergo wear and tear, introducing subtle yet consequential faults that may go unnoticed. Given the pervasive dependence on machinery, the early and precise detection of these faults becomes a critical necessity. Detecting faults at an early stage not only prevents expensive downtimes but also significantly improves operational efficiency and safety standards. This research focuses on addressing this crucial need by proposing an effective system for condition monitoring and fault detection, leveraging the capabilities of advanced deep learning techniques. The study delves into the application of five diverse deep learning models—LSTM, Deep LSTM, Bi LSTM, GRU, and 1DCNN—in the context of fault detection in bearings using accelerometer data. Accelerometer data is instrumental in capturing vital vibrations within the machinery.

Five years ago, a new experiment in passenger air transportation for Atlantic Ocean crossings was introduced. It was given the acronym known as ETOPS and involves the development of passenger aircraft having only two-engines utilized for flights over such critical routes. The essence of the concern generated in this study is summarized by the safety analysis of Dr. Robert Besco, who states, “ETOPS is troublesome because the failure of only one system on an aircraft [In this case an engine] should not cause that aircraft to have to operate under emergency conditions.” Previously, a major cornerstone of civil aviation safety was the concept of providing multiple engine redundancy with a minimum of three-engines required for such critical flights.

The Marshall Space Flight Center (MSFC) has been given the responsibility for conceptual development of the Geostationary Earth Observatory (GEO) element of NASA's Mission to Planet Earth program. Because these multi-instrument geostationary satellites will orbit over given points on the ground, they will each provide continuous observation of large regions of the Earth and will complement other data gathering facilities in low Earth orbit (LEO) such as the polar platforms of the Earth Observing System (EOS) and the Earth Probe satellites which operate in a variety of specialized LEO's. These various systems will operate over a 15-year period to obtain data with unprecedented global and temporal coverage. Because of their Earth-fixed position, the GEO instruments will provide high temporal resolution while the LEO instruments will provide data having higher spatial and spectral resolution.

The “new generation” of large satellites like ERS-1 requires modular thermal balance testing due to the physical size. The purpose of this paper is to outline the experience gained from the ERS-1 Payload Thermal Balance Test. The first part of the paper highlights the test set-up, the earthshine compensation and the selected test phases. The second part describes the temperature uncertainty approach and test correlation criteria defined for the thermal analyses and tests. The third part concentrates on the test correlation with emphasis on the thermo-optical properties of the Optical Solar Reflectors (OSRs) in the Xenon light of the simulated sun and the temperature dependent linear conductance of the honeycomb core material which played a crucial role in explaining a temperature level offset. The paper is understood as complement to the paper presented in 1987 - Thermal Control and Design of the ERS-1 Payload -.

Unprecedented rates of change in the economic equations of air transport infrastructure are impacting military, NASA and civilian fleets. Military aero-asset operational lifespans are being continually assessed for extension, and younger assets are tasked to higher levels of mission dispatch reliability. NASA, post Columbia will now undergo a new round of safety and reliability assessments of structures and wiring on the space shuttle fleet to ensure a safe return to flight. New FAA regulations to improve aging airplane structural and wiring safety motivate comprehensive change in the approach to aviation maintenance. There are concerns that these challenges of improved reliability and life extension will further strain the resources of DOD/NASA and economic health of the civilian aviation industry.

A major challenge of a System Engineering approach lies in its ability to promote an efficient Process/Method/Tools environment that leads to an efficient and accurate System Referential Repository. The key factor is the definition of a centralized system referential repository that is shared by the various stakeholders involved in the success of industrial projects, including customers, system architects, hardware and software development suppliers, validation and safety teams. This paper describes the development of a use case modeled with the most appropriate tool-chain that fulfills the above System Engineering expectations. Based on standard documents (INCOSE Handbook, ARP4754) and on experience achieved by the development of many System Engineering projects, a methodological approach is defined.

Shuttle Transoceanic Abort Landing (TAL) sites, located on the African coast and in Spain, require an emergency medical capability for astronauts who may be injured in an abort landing. The remote African TAL sites present unusual medical planning and logistical problems. Two broad options to meet the challenge of providing advanced emergent medical care at TAL sites were explored by the Department of Defense (DOD) and the National Aeronautics and Space Administration (NASA). The first option considered using a modified surgical response team, and the second involved using physician/medical technician teams. The physician/technician team concept proved the more cost-effective solution for providing medical support in these regions. Research on the logistics of blood procurement, blood refrigeration, power, air evacuation, and search and rescue (SAR) requirements led to the development of an effective TAL site astronaut medical support system.

Under a program funded by the Air Force Research Laboratory (AFRL), Advanced Cooling Technologies, Inc. (ACT) has developed a series of passive thermal management techniques for cooling avionics. Many avionics packages are often exposed to environment temperatures much higher than the maximum allowable temperatures of the electronics. This condition prevents the rejection of waste heat generated by these electronics to the surrounding environment and results in significant ambient heat gain. As a result, heat must be transported to a remote sink. However, sink selection aboard modern aircraft is limited at best. Often, the only viable sink is aircraft fuel and, depending on mission profile, the fuel temperature can become too high to effectively cool avionics. As a result, the electronic components must operate at higher than intended temperatures during portions of the mission profile, which reduces component lifetime and significantly increases the probability of failure.

Aviation industry is striving to leverage the technological advancements in connectivity, computation and data analytics. Scalable and robust connectivity enables futuristic applications like smart cabins, prognostic health management (PHM) and AI/ML based analytics for effective decision making leading to flight operational efficiency, optimized maintenance planning and aircraft downtime reduction. Wireless Sensor Networks (WSN) are gaining prominence on the aircraft for providing large scale connectivity solution that are essential for implementing various health monitoring applications like Structural Health Monitoring (SHM), Prognostic Health Management (PHM), etc. and control applications like smart lighting, smart seats, smart lavatory, etc. These applications help in improving passenger experience, flight operational efficiency, optimized maintenance planning and aircraft downtime reduction.