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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.

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.

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.

Guidelines for designing you-are-here (YAH) maps aboard International Space Station (ISS) are proposed, based on results from previous 3D spatial navigation studies conducted by our research group and colleagues. This paper reviews terrestrial YAH maps, the common errors associated with them, and how to appropriately implement what is known from terrestrial to micro-gravity YAH maps. We conclude with a creative example of an ISS YAH map that utilizes given guidelines and information visualization techniques.

The XMM-NEWTON satellite is the ESA X-ray spaceborne observatory covering the soft X-ray portion of the electromagnetic spectrum. XMM-NEWTON has been put in orbit on December, 10th 1999 by an Ariane 5 single launch. The spacecraft has a conventional thermal design that takes full advantage of the stable environment provided by its high altitude/long period orbit and by the limited variation of solar attitude angles in order to provide a stable platform for the telescope system. The precise geometry and alignment of the telescope system impose strict temperature requirements so that not only temperature gradients have to be kept small but also, and more importantly, time-variations of the gradients have to be minimised. In the paper, the thermal behaviour of the spacecraft as verified by its thermal test programme is compared with the early in-orbit temperature measurements.

High quality rivet installation is of critical importance to the aerospace industry, and the existence of gaps between the rivet head and the countersink is undesirable. Detection of gaps traditionally involves sectioning through rivet joints. Two concerns exist for this method of evaluation: it provides data only from the sectioned plane, and it has potential to alter the gaps. X-ray computed tomography (CT) was used to validate the effectiveness of the tradition sectioning method. It was revealed that the sectioning process generally increased the size of gaps. CT images also revealed that the gaps are not necessarily uniform around the rivet.

LiquidPiston Inc. has developed a new engine that can run on multiple fuels, including diesel, jet fuel, and gasoline. This platform uses an optimized thermodynamic cycle and a new rotary engine architecture and could increases flight endurance over conventional UAV engines by greater than 50%.

This SAE Metric Aerospace Standard (MA) provides dimensional, performance, testing and other requirements for high strength, thin wall, double head box and combination wrenches which possess an internal wrenching design so configured that, when mated with hexagon (6 point) fasteners, they shall transmit torque to the fastener without bearing on the apex of the fastener's wrenching points. This standard provides additional requirements beyond ANSI B107.9 appropriate for aerospace use. Inclusion of dimensional data in this document is not intended to imply all of the products described therein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.

Workspace is an important function for human factors analysis and is widely applied in product design, manufacturing, and ergonomics evaluations. This paper presents the workspace analysis and visualization for Santos™ upper extremity, a new virtual human with over 100 DOFs that is highly realistic in terms of appearance, behavior, and movement. Jacobian Rank deficiency method is implemented to determine the singular surfaces. The joint limits are considered in this formulation; three types of singularities are analyzed. This closed-form formulation can be extended to numerous different scenarios such as different percentiles, age groups, or segments of body. A realtime scheme is used to build the workspace library for Santos™ that will study the boundary surfaces off-line and apply them to Santos™ in the virtual environment (Virtools®). To visualize the workspace, we develop a user interface to generate the cross section of the reach envelope with a plane.

This standard is applicable to the marking of aerospace vehicle electrical wires and cables using ultraviolet (UV) lasers. This standard specifies the process requirements for the implementation of UV laser marking of aerospace electrical wire and cable and fiber optic cable to achieve an acceptable quality mark using equipment designed for UV laser marking of identification codes on aerospace wire and cable. Wiring specified as UV laser markable subject to AS4373 Test Methods for Insulated Electric Wire and which has been marked in accordance with this standard will conform to the requirements of AS50881.

This standard is applicable to the marking of aerospace vehicle electrical wires and cables using ultraviolet (UV) lasers. This standard specifies the process requirements for the implementation of UV laser marking of aerospace electrical wire and cable and fiber optic cable to achieve an acceptable quality mark using equipment designed for UV laser marking of identification codes on aerospace wire and cable. Wiring specified as UV laser markable subject to AS4373 and which has been marked in accordance with this standard will conform to the requirements of AS50881.

This paper reviews today's aircraft wing production assembly methodology and technologies as well as innovative ideas for advancing the high-level wing assembly state-of-the-art. Automated wing assembly systems are only being utilized to rivet/fasten first level subassemblies like panels, spars, and ribs. All other high level assembly tasks are performed manually, incurring associated increases in recurring costs due to production inefficiencies, long lead times, expensive rate tooling, and difficult assembly tasks performed inside small wing compartments. Existing assembly methods, process parameters, and the process characteristics of manual, machine, and man/machine systems provide many opportunities for improving wing assembly.

Due to the part size and technological limitations of the available assembly equipment, traditional wing manufacturing has consisted of a three stage process. Parts are first manually tacked together in an assembly jig, They are then removed from the jig, rotated horizontally and craned into an automated fastening machine. Finally they are removed from the fastening machines and craned to a third station where the manual tacks are removed and the parts are prepped for final wing box assembly. With the advent of electromagnetic riveting (EMR) and the traveling yoke assembly machine this traditional approach has been replaced with single station processing. Wing panels and spars can now be automatically tacked together under continuous clamp up in their assembly jigs using EMR. This eliminates the requirement for disassembly, debur and cleaning required with the manual process.

Results of a recent low-speed wind-tunnel investigation conducted to define the forebody flow on a 16% scale model of the NASA High Angle-of-Attack Research Vehicle (HARV), an F-18 configuration, are presented with analysis. Measurements include force and moment data, oil-flow visualizations, and surface pressure data taken at angles of attack near and above maximum lift (36° to 52°) at a Reynolds number of one million based on mean aerodynamic chord. The results presented identify the key flow-field features on the forebody including the wing-body strake.

Instrumentation that has been used for characterization of mixed-phase and glaciated conditions in the past, like the OAP probes, are subject to errors caused by variations in diffraction on the images away from the object plane and by the discrete nature of their particle detection and sizing. Correction methods are necessary to consider their measurements adequate for high ice water content (IWC) environments judged to represent a significant safety hazard to propellers and turbofan engine operability and performance. For this reason, within the frame of EU FP7 HAIC project, instrumentation characterization and validation is considered a major element need for successful execution of flight tests campaigns. Clearly, instrumentation must be sufficiently reliable to assess the reproducibility of artificial clouds with high ice water content generated in icing tunnels.

Through this work, Wind River and Airbiquity look to enable secure and intelligent software updates and data management for these vehicles through over-the-air (OTA) programming technology. The work may also lead to similar solutions for traditional aerospace and unmanned aircraft system (UAS) industries.

The microstructure characterization of tubular wicks is discussed using an image analysis method, mercury intrusion porosimetry and Arquimedes method. The central objective of this work is to determine the wide convenience of the image analysis technique for wick characterization. It is demonstrate that the image analysis technique is an appropriate tool to determine correlation function, total porosity and pore size distribution in two-dimensional (2-D) binary images of microstructures. The correlation function is used to simulate the 3-D reconstruction of porous structure. The images were obtained from a set of wick samples made of sintered nickel, through scanning electronic microscopy (SEM). A computer program (Imago) was developed and used in the work. The mercury intrusion porosimetry is also used to provide information about the breakthrough diameter of porous material. Results show porosity of about 60% and effective pore size less than 4 μm.