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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.

Pneumatic, manually operated, drilling machines are used to produce a significant proportion of all holes drilled during wing manufacture. Drilling machine design and the manual drilling process has not changed significantly in decades. By employing miniature, low power, electronics and interfacing techniques, a monitoring system has been developed. This system enables improved process control of the manual drilling operation. Machine calibration management, measurement of drill performance, jig drilling error control and asset management are some of the benefits attainable. This project will hopefully encourage others to discover the potential for improving historically established processes, by employing modern technological developments.

This paper describes some of the design solutions adopted in solving two major problems besetting man-powered aircraft in use: that of breakage and storage. It describes work leading up to the building and testing of “Phoenix”, a man-powered aircraft with a polyester-film inflatable wing. The paper deals mainly with aspects relating to the wing design and construction.

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.

“Melmoth,” an amateur-designed and built light airplane, has a number of features unusual in general aviation aircraft, aiming to combine comfort, high cruising speed, aerobatic capability and transoceanic range in a single compact machine. Among these are high wing loading, large internal fuel capacity, variable aileron incidence, double-slotted Fowler flap, automatic fuel tank switching, internal cowl flaps, and an all-flying T-tail.

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.

THIS PAPER reviews VTOL problems, indicating probable ways toward optimization of whole lifting and propelling system. Also discussed are the power and thrust requirements for optimum cruise and vertical take-offs and landings for propeller-driven and jet-propelled aircraft. Three speed ranges offer the most promise for VTOL aircraft, if thrust requirements for cruise and take-off are to match. The ranges are centered around Mach numbers of 0.65, 0.8, and 2.0+. There is a possibility of overcoming the high thrust needed for hovering by use of bypass augmentation, special hovering jets, or favorable ground effects, the author reports.

STRUCTURAL MATERIALS for Mach 3 jet transports pose difficult problems for the design engineer. Reasons for this problem are the incomplete information available on the many possible metals and the diversity of critical properties that are added by supersonic requirements. The material properties discussed in this paper include tensile strength, resistance to crack propagation, ease of fabrication, weldability, and thermal expansion. Cost factors are also considered. The structural configuration of the wing and fuselage is an example of the complexity of the material selection problem. The wing may be rigidity-critical, and the fuselage strength-critical; each requires diferent material properties to solve the problem.*

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.

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.