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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).

The onboard “SODART” telescope silicon detector cooling system of the “Spectrum-X-Gamma” observatory, which is designed for the space objects X-ray radiation study, is described. The scale-down model of the passive cooling system description and thermal vacuum test results of this model are given. In the real cooling system the minimal detector temperature at 300 mW heat release is expected about 107 K.

In recent years there has been increasing interest in quantifying the emissions from aircraft in order to generate inventories of emissions for climate models, technology and scenario studies, and inventories of emissions for airline fleets typically presented in environmental reports. The preferred method for calculating aircraft engine emissions of NOx, HC, and CO is the proprietary “P3T3” method. This method relies on proprietary airplane and engine performance models along with proprietary engine emissions characterizations. In response and in order to provide a transparent method for calculating aircraft engine emissions non proprietary fuel flow based methods 1,2,3 have been developed. This paper presents derivation, updates, and clarifications of the fuel flow method methodology known as “Fuel Flow Method 2”.

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.

RADIATION can produce almost instantaneous failure of modern aircraft lubricants, tests at Southwest Research Institute show. Two types of failures demonstrated are rapid viscosity rise and loss of heat conductivity. Furthermore, it was found that lubricants can become excessively corrosive under high-level radiation. Generally speaking, the better lubricants appeared to improve in performance while marginal ones deteriorated to a greater extent under radiation. When the better lubricants were subjected to static irradiation prior to the deposition test, there was a minor increase in deposition number as the total dose was increased.

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.*

NEW WELDING processes are dropping costs while providing improvements in weld quality. This paper describes some of the more promising new developments in pressure and fusion welding and brazing. Included in the discussion are ultrasonic, high frequency resistance, foil seam, magnetic force, percussion, friction, and thermopressure welding and diffusion bonding. The description of adhesive bonding includes the development of glass or ceramic materials as structural adhesives.*

Mobility is in the midst of an electric revolution, propelled by industry innovators such as magniX. Headquartered in Redmond, Washington, the magniX team is focused on revolutionizing electric motors for commercial aviation applications.

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.

The permanently increasing number of convenience and safety functions leads to higher complexity of in-car electronics and the rapidly growing amount of sensors, actuators and electronic control units places higher demands on high- speed data communication protocols. Safety-critical systems need deterministic protocols with fault-tolerant behavior. The need for on-board diagnosis calls for flexible use of bandwidth and an ever-increasing number of functions necessitates a flexible means of extending the system. None of the communication solutions available on the market until now (like CAN or TTP) have been able to fulfill all these demands. To solve these problems, BMW together with several semiconductor companies has developed a new protocol for safety-critical applications in automotive vehicles.

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.*

To enable the tests required for development work to be performed with maximum efficiency, the Zwick Roell Group (ZwickRoell) – a global supplier of materials testing machines based out of Ulm, Germany – developed a materials testing machine that can be equipped with both a temperature chamber and a high-temperature furnace.

The likelihood of transmission of potential disease agents between animals and man during spaceflight is a real concern. Development of disease exclusion lists for animals and refinement of animal containment units have been the principal means of providing protection to the crew members. Awareness of potential latent infections and a judicious use of the higher risk category of animals such as wild-caught nonhuman primates provides another level of protection. Use of high efficiency filters, gasketing, and differential air pressures have all enabled increasing levels of safety through containment of potential aerosol escape from animal habitats.

A “next generation” condensing heat exchanger for space systems has to satisfy demanding operational requirements under variable thermal and moisture loads and reduced gravity conditions. Mathematical models described here are used to investigate transient behavior of wetting and de-wetting dynamics in the binary porous system of porous tubes and porous cold plate. The model is based on the Richard's equation simplified for the zero-gravity conditions. The half-saturation distance or the zone of influence of the porous annular suction tubes on the cold-plate porous material will be in the range of 1 to 10 cm for the time scales ranging from 100 to 10,000 seconds and moisture diffusivity in the range of D = 10-4 to 10-6 m2/s.

In a 2-year program sponsored by SJAC, an aqueous electroplating process using alkaline Zn-Ni with trivalent chromium post treatment is under evaluation for high strength steel for aircraft application as an alternative to cadmium. Commercial Zn-15%Ni rack/barrel plating solutions are basis for plating aircraft parts or fasteners. Brightener was reduced from the original formula to form porous plating that enables bake-out of hydrogen to avoid hydrogen embrittlement condition. Properties of the deposit, such as appearance, adhesion, un-scribed corrosion resistance, and galvanic corrosion resistance in contact with Al alloy, were evaluated. Coefficient of friction was compared with Cd plating by torque-tension measurements. Evaluation of the plating for scribed corrosion resistance, primer adhesion, etc. will continue in FY2007.

In spite of environmental issues related to cadmium and its electroplating process, electroplated cadmium is still extensively used in the aerospace and defense sectors. This trend is likely to continue especially for high strength steels because cadmium provides the best known corrosion and embrittlement protection for this application. Consequently, the environmental concerns related to the cadmium electroplating have been addressed using an alternative Zero-waste Physical Vapor Deposition (Z-PVD). This method does not use liquids, it recycles cadmium in situ, and is free of hydrogen embrittlement. The Z-PVD process is now in commercial production for the aerospace fasteners. The quality of the coatings has been at least equal to that of the electroplated cadmium.