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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.

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.

The requirement for crew resource management (CRM), or aircrew coordination training (ACT) in military parlance, has been well documented and attested to. In addition, aircraft systems training has become more intense and more in-depth in the new aircraft designs, especially in multi-crew and complex aircraft such as the MV-22 Osprey Tiltrotor. (see Figure 1) Former training systems detailed training procedures that called for classroom training and simulation/simulator training followed by flight training. Improvements in aircraft flight skills training provide increased flying training capability coupled with reduced training time by integrating a mixed simulation/flight training syllabus, e.g. two to three simulation periods followed by one or two flight training periods covering the same material/skills. In addition, the simulation training will introduce new skills; the following flight periods will further refine/hone those skills.

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.

The Boeing Company in Mesa, Arizona, has been conducting a concept design study of a roadable helicopter called the “Converticar” to assess its feasibility. This is a twin-engine vehicle with twin retractable coaxial counter-rotating rotors. The purpose of the study is to describe a vehicle that carries four passengers in the equivalent of a luxury car that also can fly like a helicopter, and can be priced like a luxury car. To come near this cost goal, the production rate must be on the order of 500,000 units a year. At that rate there is no chance of training a comparable number of pilots each year. So the machine must fly and navigate autonomously, with the pilot just dialing in where he/she wants to go. Technologically, the concept appears to be feasible. Modern design processes, new materials, and improved manufacturing process should allow the Converticar to be built at the prescribed rate when the proper infrastructure for manufacturing it is made available.

The euces project was initiated to be prepared for the future role of EADS as stage system prime for stage and launcher developments. Launcher stages for NGLV need to meet ambitious mission and operational demands. The paper will present a brief overview of the currently existing COMPONENT libraries and its possibilities as well as an application example which will be a simplified functional model of the ARIANE 5 EPS upper stage w.r.t. physical model formulation of its incorporated components, its schematic, data initialisation and simulation results obtained. The simulation results will be compared to flight data of a dedicated flight.

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.

This paper discusses the findings for [Interior] Configuration Options, Habitability and Architectural Aspects of a first human spacecraft to Mars. In 2003 the space architecture office LIQUIFER was invited by the European Space Agency’s (ESA) AURORA program committee to consult the scientists and engineers from the European Space and Technology Center (ESTEC) and other European industrial communities with developing the first human mission to Mars, which will take place in 2030, regarding the architectural issues of crewed habitats. The task was to develop an interior configuration for a Transfer Vehicle (TV) to Mars, especially a Transfer Habitation Module (THM) and a Surface Habitat (SHM) on Mars. The total travel time Earth - Mars and back for a crew of six amounts to approximately 900 days. After a 200-day-flight three crewmembers will land on Mars in the Mars Excursion Vehicle (MEV) and will live and work in the SHM for 30 days.

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.

For human beings who have been reared on the earth with its 1 G gravitational field, the condition of weightlessness is a world with which we are unfamiliar. Even if the layout and equipment configuration of a spacecraft designed to compensate for operation under Zero-G conditions, there are some things which are not effective under actual weightless conditions. In the design of a manned spacecraft, it is necessary to accumulate design data on human performance in a weightless condition, then to undertake design evaluations and verification under weightless conditions. In this paper, testing for the purpose of evaluating the effectiveness of Zero-G simulation using neutral buoyancy, conducted first of all in Japan, and recommendations on the equipment and Facilities required to conduct such simulations, are described.

This paper describes the development of a set of algorithms that find the takeoff gross weight of an aircraft for given vehicle and engine characteristics, and mission requirements. A major objective was to find the most elementary set that would still yield useful answers. The result was a set that could be encoded on an inexpensive programmable pocket calculator with only 24 lines of code. Results are compared with actual characteristics of an executive jet and its derivative versions.

Combat aircraft maneuvering at high angles of attack or in landing approach are likely to encounter conditions where the flow over the swept wings is yawed. This paper examines the effect of yaw on the spectra of turbulence above and aft of the wing, in the region where fins and control surfaces are located. Prior work has shown the occurrence of narrowband velocity fluctuations in this region for most combat aircraft models, including those with twin fins. Fin vibration and damage has been traced to excitation by such narrowband fluctuations. The narrowband fluctuations themselves have been traced to the wing surface. The issue in this paper is the effect of yaw on these fluctuations, as well as on the aerodynamic loads on a wing, without including the perturbations due to the airframe.

MBB and Rockwell, under DARPA/NAVAIR and GMOD contract, are currently designing an experimental aircraft which will be dedicated to demonstrate “enhanced fighter maneuverability” (EFM) and supermaneuverability in particular. The aircraft is designed to break one of the last barriers left in aviation, the stall barrier. It will be able to perform tactical maneuvers up to 70° angle of attack and thus achieve very small radii of turn. Such highly instantaneous 3-dimensional maneuvers are of significant tactical value in future air combat with all aspect weapons. Key to the penetration into this unexplored flight regime is thrust vectoring in pitch and yaw. This feature is also used to enhance agility in critical flight conditions and to enhance the decoupling of fuselage aiming and flight path control as required for head-on gun firing.

The X-36 is a remotely piloted 28% scale model of a two-axis-unstable notional future fighter aircraft with canards, a mid-wing and features the absence of any vertical control surfaces, Figure 1. The aircraft was jointly developed by the NASA Ames Research Center and McDonnell Aircraft & Missile Systems and flight tested at the NASA Dryden Flight Research Center. Objectives of this program were to demonstrate fighter aircraft agility for a vertical tailless configuration and to demonstrate the development of a low cost alternative to full size prototype aircraft. This paper presents some aspects of the subsystem integration methodology used to develop the X-36 Tailless Agility Research Aircraft.

The X-29A is the first X-series experimental aircraft developed in the United States since the mid-sixties. The X-29A is a technology demonstrator aircraft that integrates several different-technologies into one airframe. Among the technologies demonstrated are the aeroservoelastically tailored composite forward swept wings, close coupled canards, discrete variable camber wing, triplex digital flight control system with analog backup, thin supercritical wing, three surface pitch control, large negative static margin and the integration of these technologies into the X-29 airframe. This paper deals with the issue of technology integration of five of the X-29A subsystems and the early design decision to use existing aircraft, components whenever and wherever possible. The subsystems described are the X-29 aircraft Hydraulics System, the Electrical Power System, the Emergency Power System, the Aircraft Mounted Accessory Drive and the Environmental Control System.

A cooperative effort has been defined between NASA-Ames/Dryden Flight Research Facility and NASA-Langley Research Center in support of the X-29A Advanced Technology Demonstrator. The effort involves three phases: flight testing, wind-tunnel testing in the National Transonic Facility, and computational support of each experimental phase. These efforts are primarily aimed at understanding the complex flow phenomena and component interactions associated with the X-29A. Each phase of the effort is discussed in detail and initial data comparisons are presented. In summary, the synergistic effects of the complementary phases are identified, which will enhance the understanding of the unique aerodynamics of the X-29A.

It was anticipated that during X-29 extended duration, high angle-of-attack flight (40 to 70 deg), aircraft ECS performance would significantly degrade. Computer modelling of the system indicated that the performance of the ECS decreased as the angle of attack increased. Modifications to improve system performance were analyzed and, as a result of this analysis, ECS hardware modifications have been incorporated on the aircraft. The High-Alpha Flight Test Program has proven the validity of these modifications. To date, the ECS on Ship No. 2 has performed well within its nominal operating parameters in the high-alpha regime.

Paralleling synchronous generators requires a priori voltage matching and frequency synchronization. Exceeding normal limits can lead to severe electrical transients. The classical three-phase short circuit analysis is extended to include the case of two initially unloaded synchronous generators. An analytical solution is developed neglecting winding resistances and saturation. Of particular interest is the tendency to induce negative field currents that cause inverse voltages across the rotating rectifier in a brushless design. Typical aircraft generator parameters are used to predict the paralleling transient vs. initial rotor electrical angle mismatch. Results are compared to simulation and limited test results.

The first flight of a delta wing aircraft took place in the United States at the Muroc AFB Flight Test Center on 18 September 1948. The aircraft, Convair No. 7002, Air Force S/N 46-682 and designated the XF-92A was piloted by Convair's Manager of Flight Research, E.D. “Sam” Shannon. The author witnessed this historic flight as a Flight Test Engineer on the project. Studies and wind tunnel tests for a supersonic interceptor were conducted at the Vultee Division of Consolidated Vultee Aircraft Corporation (Convair) in 1945. These studies led to the selection of the 60° delta wing plan form. This paper reviews the major differences between the thin wing XF-92A and the thick wing DM-1 glider (never flown) designed by Alexander M. Lippisch in Germany at the close of World War II. The XF-92A used a fully hydraulic irreversible control system for its elevons and rudder. The only airplanes up to this time with fully hydraulic controls were the Northrop XB-35 and the YB-49 flying wings.

Current and future generations of transport aircraft are characterized by a high level of automation. This automation is intended to assist the flight crew and make it possible for a crew of two persons to operate these aircraft for all types of flights, including those of extremely long duration. While one of the design goals of automation is to reduce crew workload, little is known about the true relationship between workload and automation. This paper discusses the approaches taken by Airbus Industrie when designing increasing levels of automation into their aircraft. It also addresses the Airbus program of workload research and the need to direct specific attention to the relationship between workload and automation.