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Pitot probes and Total Air Temperature (TAT) probes are critical to aircraft performance. They are also susceptible to becoming overwhelmed and produce erroneous outputs when flying in icing conditions, especially in high altitude ice crystal situations. When the probes are overwhelmed with ice crystals, it can have significant impacts to aircraft operations. Through design and process iterations, Collins Aerospace (also known as Rosemount Aerospace™), has developed new Appendix D compliant pitot and TAT probes that are much more capable in high ice crystal content icing environments which greatly reduce the adverse risks to the aircraft and engine systems that depend on these probes.

Certification standards for high-assurance systems include objectives for demonstrating compliance of process artifacts such as requirements and code with style guidelines and other standards. With the emergence of model-based development, similar objectives have been specified that apply to models. Demonstration of compliance is often achieved by employing a static analysis linter tool. This paper describes Resolint, an open-source, lightweight linter tool for checking compliance of Architecture Analysis and Design Language (AADL) models with modeling guidelines. AADL enables engineers to describe the key elements of distributed, real-time, embedded system architectures with a sufficiently rigorous semantics. In addition, AADL provides an annex mechanism for extending the base language, enabling new kinds of analyses and tool support. Resolint uses the AADL annex capability to provide a language for specifying style guide rule sets.

In the development of electric actuators, the electric motor to drive the actuator is quite often selected from a set of available motors that have been previously used on other similar programs, or based on legacy experience, or from those that are commercially available seeming to fit for the purpose. Scheduling and budgetary constraints pose a restriction on design and development of a new electric motor specifically for the required application. Generally, these electric motors have minimal weight but deliver maximum output power because of which they tend to heat up rapidly. Such rapid heating can lead to issues such as insulation damage or weakening of the strengths of permanent magnets used in the rotors of permanent magnet induction motors. In such cases, very early in the design phase, it becomes necessary to estimate the temperature rise of the electric motor in a cost effective and rapid way so that the best suitable motor that gives minimal temperature rise is selected.

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.

Evolving of aircraft design towards further electrification requires safe and fault-free operation of all the components. More electric aircraft are increasingly utilizing electro-mechanical actuators (EMA). EMAs are prone to jamming and subsequent failure due to large forces on the shaft. Large forces are generated due to the high reflected inertia of the electric machine rotor. To limit the force acting on the shaft, a torque limiting device is connected to the power train which can separate the rotating mass of the electric machine from the power train. In this paper, a concept of integration of torque limiter and the electric machine rotor is presented to reduce overall volume and mass. It is connected closely with the rotor, within the motor envelope. A commercially available torque limiter and an electric machine designed for actuator application are used to demonstrate the concept. While essential for safety, the torque limiter adds to the mass and size of the overall EMA.

The aircraft jet engine is one of the most complex multivariable systems with multiple inputs and multiple outputs. To attempt to optimize control functions or to address diagnostic problems, a detailed knowledge of all jet engine design parameters and performances is required. Although jet engines have been around for almost a century, there are only a few companies in the world presently designing and manufacturing them; as such these companies possess detailed knowledge of all relevant design characteristics and performance parameters. In the event where jet engine technical details are unknown, or only a few of them are known from manufacturer’s catalogues, the challenge becomes how to calculate and extrapolate critical performance parameters based on only fuel flow, jet exhaust temperature and total thrust.

As unmanned aerial vehicles (UAVs) fill a wider and wider variety of civic, scientific, and military roles—analysts predict that the UAV market will be the most dynamic growth sector of the decade in terms of the world aerospace industry. As a result, UAV research and development will contribute to a major portion of spending in the next decades—with a significant emphasis on propulsion technologies. This book will cover several UAV propulsion technologies, ranging from modification of conservative designs to assessing the potential of unconventional arrangements. Each chapter provides a glimpse of how researchers are leveraging different fuel types, powerplants, and system architectures in the pursuit of powerful, efficient, and robust UAV propulsion.

Aviation propulsion development continues to rely upon fossil fuels for the vast majority of commercial and military applications. Until these fuels are depleted or abandoned, burning them will continue to jeopardize air quality and provoke increased regulation. With those challenges in mind, research and development of more efficient and electric propulsion systems will expand. Fuel-cell technology is but one example that addresses such emission and resource challenges, and others, including negligible acoustic emissions and the potential to leverage current infrastructure models. For now, these technologies are consigned to smaller aircraft applications, but are expected to mature toward use in larger aircraft. Additionally, measures such as electric/conventional hybrid configurations will ultimately increase efficiencies and knowledge of electric systems while minimizing industrial costs.

Development of higher-voltage electrical systems in vehicles has been slowly progressing over the past few decades. However, tightening vehicle efficiency and emissions regulations and increasing demand for onboard electrical power means that higher voltages, in the form of supplemental 48 V subsystems, may soon be nearing production as the most cost-effective way to meet regulations. The displacement of high-wattage loads to more efficient 48 V networks is expected to be the next step in the development of a new generation of mild hybrid vehicles. In addition to improved fuel economy and reduced emissions, 48 V systems could potentially save costs on new electrical features and help better address the emerging needs of future drivers. Challenges to 48 V system implementation remain, leading to discussions by experts from leading car makers and suppliers on the need for an international 48 V standard. Initial steps toward a proposed standard have already been taken.

“Spotlight on Design” features video interviews and case study segments, focusing on the latest technology breakthroughs. 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. In the episode “Diagnostics and Prognostics: Proactive Maintenance and Failure Prevention” (21:04), Delphi engineers explain how they leverage the growing number of sensors and computing power in vehicles to diagnose and proactively solve emerging mechanical or electronic problems, before a breakdown occurs. This video also looks at the next generation of automotive telematics, with HEM Data demonstrating how in-vehicle data acquisition is used to monitor the inner workings of vehicles.

A key topic of many technical discussions has been the development of alternative fuels to power the compression ignition engine. Reasons for this include the desire to reduce the dependency on petroleum-based fuel and, at the same time, to reduce the particulate matter (PM) and NOx emissions. Also, there has been interest generated in the diesel engine because of the reduction in greenhouse gases that has been proposed during the 2008-2012 time frame in Europe and the regulations that affect diesel engines in the United States.

The 53 technical papers in this book show the improvements and design techniques that researchers have applied to performance and racing engines. They provide an insight into what the engineers consider to be the top improvements needed to advance engine technology; and cover subjects such as: 1) Direct injection; 2) Valve spring advancements; 3) Turbocharging; 4) Variable valve control; 5) Combustion evaluation; and 5) New racing engines.

This report profiles the development and unlimited potential of electric steering technology--an innovation expected to fundamentally change the way automobiles are designed, produced, and marketed. Electric Steering offers information on how this revolutionary steering system evolved, and the effects its implementation will have on America's largest manufacturing industry. Chapters include: Steering Basics Electronic Steering The Market Drivers The Future and more