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The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.

A Web-based version of the aircraft design program ACSYNT has been created. “Web-ACSYNT” provides the user with a familiar user interface and is accessible from multiple platforms. Analyses are based upon a set of baseline aircraft models which can be modified through a carefully selected set of parameters related to weight, aerodynamics, propulsion, economics, and mission. The software is intended to become one of the models that comprise the Aviation System Analysis Capability (ASAC) currently being developed by NASA under the Advanced Subsonic Technology (AST) program.

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.

The “Rigidization-on-Command”™ (ROC™) resin development has focused on the development of resin systems that use UV light cure for rigidization. Polymeric sensitizers have been incorporated into the resin formulations to promote cure using Pen-Ray lamps and UV light-emitting diodes (LED's). Formulations containing the polymeric sensitizers were examined by FTIR and DSC. Complete cure was observed after 15 min. exposure with the Pen-Ray lamps. Performance of the Pen-Ray lamps and UV LEDs was thoroughly characterized. Thermal models were developed to optimize the performance of the of the MLI insulation thermal oven used for orbital cure of the boom. Results show that -12°C is the lowest temperature required for cure of the ROC™ resin systems.

To a large degree all of us at one time or another have envisioned our “Over the Rainbow” version of a future should be. System engineers envision perfect harmony between vehicle aerodynamics and avionics integration. The program manager dreams of schedules and funding well within the projected budget. Then reality; budget constraints, backward compatibility, technology availability, schedule problems, and etc. This paper is intended to recognize the “dreamer” and at the same time offer a means of reconciliation to the real world. We will address advanced avionics architectures and a transitionary means to attain our goals and objectives. An “Avionics System Index” will be presented which defines and specifies a means of describing and partitioned avionics configuration.

Mathematical modeling and control of artificial ecosystems, such as MELISSA, require first the study of physical and biological characteristics in optimal and limiting conditions. Following the previous determination of the stoichiometric equations (Spirulina compartment) and regarding the two phototrophic compartments of MELISSA (Rhodospirillaceae and Spirulina), we have first to focus our control study on the growth kinetics for the light source. In this paper, we recall the theoretical equations of microbial growth kinetics and emphasise the problem of the light transfer in a photobioreactor. We present their adaptations to our pilot plant taking into account technological and biological specifics (lamp spectrum, working illuminated volume, growth rate,…). We then develop the principles and structure of the control system and describe tests of both the hardware and software for several steady state configurations.

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.

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.*

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.

The purpose of this ARP is to provide criteria that will lead to and support existing regulatory standards of systems for UAM/AMM/eVTOL aircraft such that the emergency systems will facilitate egress under emergency conditions. Consideration is given to existing requirements of the FAA and to the recommendations of aircraft operators and those involved in the manufacture or use of the emergency lighting system. Occupant safety is the primary objective, with appropriate provisions for crew (pilot) system control taken into consideration. Consideration is also given to autonomous aircraft in which passengers are required to egress without the aid or direction of crew. The criteria established herein are intended to produce an emergency lighting system that will comply with the Federal and International Regulations. However, these recommendations are but one means of meeting the objective.

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.*