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The use of microprocessors for the implementation of control functions in aircraft electric systems has become a reality. This paper presents a brief survey of these systems along with a typical system block diagram. A description of the diagram highlights the advantages of microprocessor systems over existing noncomputerized control schemes. The second half of the paper discusses the adaptability of more advanced microprocessor systems in the next generation of aircraft electric systems. These powerful new computers will allow digital control and protection of single unit and paralleled generating and starting systems, as well as providing even more effective built-in-test.

This paper will discuss using Astronics “Smart Panel” illuminated control panels to control an electronic power distribution system. A discussion of wiring simplification, automatic control possibilities and real time load monitoring is presented. The challenges of retrofitting the system into older aircraft will be covered as well. The paper also explains Electronic Circuit Breaker technology, arc fault protection, panel lighting technologies, control bus options, displays, and human input technology (buttons and knobs).

When looking into using PCMCIA PC Cards in the avionics market, three areas must be researched. The first is what are the applications and benefits of using the PC Cards while in flight, followed by the applications and benefits on the ground, and thirdly on how to make a PC Card that would stand up to the rugged avionics environment. PCMCIA PC Cards can be used in all aspects of flight. Three possible applications on the ground are; paperless documentation, modifications, flightline changes. Once airborne, PC Cards can be removed and a different functionality card can be inserted. One PC card socket can be used for many different functions during one flight. Some of the possible applications for PC Cards inflight are; flight plan changes, backup Line Replaceable Units (LRUs), and solid state data collection.

The Focke-Wulf Fw 190 was one of the truly outstanding fighter aircraft of the Second World War. It distinguished itself over all fronts on which the Luftwaffe fought in conditions ranging from arctic wastes to the deserts of North Africa. The Fw 190 represented the epitome of conventional piston-engine fighter design on the threshold of the jet age. Conceived nearly sixty years ago, flying for the first time on the eve of the war in 1939 and acknowledged as “the best all-around fighter in the world” in the mid-war years, derivatives of the Fw 190 were still pushing the ultimate capability boundary for this class of aircraft at war's end in 1945 (reaching maximum level true airspeeds of 470 mph [about Mach 0.7] at altitudes of well over 40,000 feet). This paper assesses the design attributes and technology approaches, including innovative use of advanced electrical systems, that were used to make the Fw 190 one of the great all-around fighters in aviation history.

A wide body aircraft carries almost a half–ton of water and ice between the cabin and skin of the aircraft. The water can get on wires and connectors, which can cause electrical problems, cause corrosion and rust, and, eventually, “rain in the plane”. The speaker is the CEO of CTT Systems that has developed a system that solves the condensation by using dry air. The speaker will discuss how condensation can be prevented and how airlines can also save maintenance costs in the process. This topic is relevant for the attendees at the Aerospace Expo, as they are decision makers who need to be aware of this issue. It is also important for the MRO shows as the attendees are on the front lines of dealing with this problem.

The airline industry seems to be providing more leisure features on planes like inflight entertainment, Internet access and Digital TV, but it seems the airline industry has ignored the issue of excess condensation on aircraft, which had plagued carriers since the birth of the airline industry. How safe are passengers when a wide body aircraft carries in excess almost a half ton of water and ice between the cabin and skin of the aircraft? Besides the added weight straining the aircraft, excess condensation soaks wires and connectors which can cause electrical shorts. There have been instances of emergency doors frozen shut, locked by ice stemming from excess water dripping inside the plane. Extra water also causes “rain-in-the-plane”, an issue that has gained national attention and causes passenger discomfort. It's time for the industry to address what has become a serious issue.

This Life Support Laboratory consists of a simulator of the spacecraft called Nautilus, which houses Air Revitalization Subsystem, Atmospheric Control and Supply, and Fire Detection and Suppression in the Equipment Area. There are supporting facilities including a Human Metabolic Simulator, simulated Low and Moderate Temperature Coolant Loop, chemical analysis bench, purified water supply, vacuum and gas supplies. These facilities are scheduled to be completed and start to operate for demonstration purposes by March 2005. There are an ARES Ground Model (AGM) and a Trace Contaminant Control Assembly in the ARS. The latter will be integrated with the AGM and a Condensing Heat Exchanger. The unit of AGM is being engineered, built, and will be delivered in early 2005 by EADS Space Division. These assemblies will be operated for sensitivity analysis, integration and optimization studies. The main goal is the achievement for optimal recovery of oxygen.

HEAT TRANSFER causes loading and starting design problems in large missile systems powered by cryogenic propellants. This manifests itself during loading as effective density variation, violent surface conditions, boiloff, and ice formation — problems which may be solved by insulating the tank. During starting it causes overheating and caviation — effects which may be reduced by recirculators and subcooled charge injections. The study described in this paper centers around liquid oxygen and its variations in heat flux rate, which affect liquid density, surface condition, and replenishing requirements. The problem areas are made apparent by consideration of a hypothetical missile system.*

eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is a powerful X-ray telescope under development by the Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany. eROSITA is the core instrument on the Russian SRG1 mission which is planned for launch in 2011. It comprises seven nested Wolter-I grazing incidence telescopes, each equipped with its own CCD camera. The mirror modules have to be maintained at 20°C while the cameras are operated at -80°C. Both, mirrors and CCDs have to be kept within tight limits. The CCD cooling system consists of passive thermal control components only: two radiators, variable conductance heat pipes (VCHP) and two special thermal storage units. The orbit scenario imposes severe challenges on the thermal control system and also on the attitude control system.

SUBSTANTIAL POWER is necessary to start the modern jet engine. Thus, starting equipment has become a major concern of air transport operators. This paper discusses the equipment used with self-contained starting systems. The authors discuss and evaluate a variety of self-contained systems: combustor, fuel-air combustion, cartridge, liquid propellant, hydraulic supported by auxiliary power units, and electric supported by APU. Possible future systems are: self-breathing systems, oxygen combustors, and liquid-oxygen-water-fuel combustors. It is emphasized that the choice of a starting system for a particular aircraft will depend on aircraft characteristics and the aircraft's intended use.*

Future space exploration missions will require a lightweight spacesuit that expends no consumables. This paper describes the design and performance of a prototype heat rejection system that weighs less than current systems and vents zero water. The system uses regenerable LiCl/water absorption cooling. Absorption cooling boosts the heat absorbed from the crew member to a high temperature for rejection to space from a compact, non-venting radiator. The system is regenerated by heating to 100°C for two hours. The system provides refrigeration at 17°C and rejects heat at temperatures greater than 50°C. The overall cooling capacity is over 100 W-hr/kg.

This paper discusses the advantages and problems associated with the use of “passive” liquid containment systems that utilize liquid intermolecular forces for propellant orientation in reduced or zero gravity environments. Liquid orientation is required to provide reliable engine restart and tank venting operations of space vehicle propulsion systems. Various liquid containment system concepts, and associated design criteria, are presented and general problem areas of interface stability, liquid slosh, and effects of thermal energy are described. Descriptions of present and planned test facilities designed to provide reduced gravity environments and extended time durations are included. It is concluded that additional design criteria in the problem areas discussed must be obtained before “passive” liquid containment systems can replace systems now used in reduced or zero gravity environments.

The commercial aviation currently accounts for roughly 2.5 % of the global CO2 emissions and around 3.5% of world warming emissions, taking into account non CO2 effects on the climate. Its has grown faster in recent decades than the other transport modes (road, rail or shipping), with an average rate of 2.3%/year from 1990 to 2019, prior to the pandemic. Moreover, its share of Greenhouse (GHG) emissions is supposed to grow, with the increasing demand scenario of air trips worldwide. This scenario might threaten the decarbonization targets assumed by the aviation industry, in line with the world efforts to minimize the climate effects caused by the carbon emissions. In this context, hydrogen is set as a promising alternative to the traditional jet fuel, due to its zero carbon emissions.

The X-Wing concept employs a single lifting system for all modes of flight. The lifting system is comprised of four very rigid, circulation control wings with blowing for lift modulation and control. For hover and low speed flight, the wings rotate such as the rotor of a helicopter. For high speed flight, the wings are stopped in an “X” configuration across the fuselage - from which the name of the concept is derived - with two forward-swept wings and two aft-swept wings. Such a vehicle is also envisioned to have an integrated gas turbine propulsive system for all flight modes. At low speeds, the gas generators) would drive a shaft to turn the wings and the circulation control compressor as well as a set of propulsive fans. For high-speed flight, the shaft would drive only the compressor and accessories as the fans propel the vehicle. The X-Wing concept has been underdevelopment for over 15 years.

The X-38 vehicle will be used to demonstrate the future technology on durable TPS for the CRV. Astrium has produced two large CMC Nose Skirt side panels for the current X-38 configuration. The design of the 3 dimensional curved and large side panels comprises a light-weight, stringer stiffened concept which compensates the thermal expansion by a system of flexible metallic stand-offs. An optimum in flexibility and stiffness to fulfil all requirements had to be found: strong and stiff enough to carry the thermo-mechanical loads, but flexible enough to realise a fastening concept which does not fail due to thermal expansion. The fastening concept has been tested on development test level. Some thermal and mechanical tests on sub-structure level confirmed the design and analysis work of the complete TPS concept.

BY working from notebook memoranda, personal correspondence files, old photographs, and the original laboratory instruments, the author has been able to gather together the story of how the Wright brothers, starting in 1899 with an idea for controlling the flight of a glider, were able, by 1903, to develop a machine that was capable of powered flight. The author describes this airplane and its engine as well as the 1904-1905 and 1908 ones. The latter was the first airplane to pass U. S. Army acceptance tests.

The substantiation of heat pipe usage in passive radiative cooling systems on temperature level (190…240) K for space optical sensors is presented. Heat pipes can be sound practice like heat conducting lines between sensor and radiator particularly at distances more 0.2 m and irreplaceable at distances (0.5…2) m. Embedding heat pipe with radiator allows to create the uniform temperature basis in case of several sensors connection to single radiator and to improve radiator efficiency. It is analyzed approach to design of thermocontrol and cooling radiative systems with heat pipes to reduce sensitiveness to external light disturbances and to enlarge area of radiative system application. The results of design, thermovacuum test and flight operation of thermocontrol radiative system samples are under discussion as well.

Selection of working fluid is one of the main criterions for designing of heat pipes thermal control systems (TCS) for space application. In this paper we will describe how we solved the task of development of the TCS with working fluid of high thermal physical properties. In 2004-2006 we developed the Engineering model of Deployable Radiator based on Loop Heat Pipe by CAST purchase order. It was developed for qualification tests. Ammonia application as LHP working fluid is stipulated by its high thermal physical properties. However Ammonia freezing temperature is of minus 77ºC. Such fact impedes Ammonia application when operation temperatures of LHP Radiator are lower than this value, for example, It takes several tens of hours to orbit a spacecraft and prepare it for work (at that moment the spacecraft is out of power supply) and the working fluid can be frozen in a condenser-radiator when the spacecraft being in the shadow over a long period of time.

A bioregenerative diet is characterized by a high proportion of foods produced on site. The production and processing of foods into either ingredients or recipes entails certain labor requirements. Ideally these labor requirements should be estimated with a high degree of accuracy. Crew time is at premium and any amount of time spent on food preparation and processing is time not spent in conducting research and any other activities devised to improve the quality of life of the astronauts. Moreover, a wide variety of tasks are involved in the food preparation of a bioregenerative diet and the labor times of these tasks do not scale or increase in uniform fashion. Predicting food preparation labor requirements for varying crew sizes will require task specific models and data. Videotape analysis is a work measurement tool used in the manufacturing industry.

The reliability and maintenance of electrical wiring and electrical components in aging aircraft have become areas of concern for the aviation industry. Numerous investigations have been conducted on the aging aspects of wiring and systems of large transport and military airplanes, with funding primarily from the FAA (Federal Aviation Administration), Air Force, and NASA. However, because of the large number of smaller general aviation aircraft in service, a need for examining the condition of wiring, electrical components and maintenance procedures for smaller aircraft exists. The Aging Aircraft Research Laboratory at the National Institute for Aviation Research (NIAR), Wichita State University, has conducted a comprehensive teardown evaluation of three high time commuter class airplanes. This teardown included assessment of aircraft wiring, electrical systems and circuit breakers through general and intrusive visual inspections and laboratory tests.