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The large optical apertures required by many space-based telescopes make thermal control of these optics a significant challenge. One technique which has been used for x-ray telescopes involves placing insulating tubes forward of the entrance aperture. The reduction in both conduction and direct view produces a thermal gradient along the tubes, increasing the effective sink temperature for the optics and reducing the effective radiant source temperature and heat flow to space. In another configuration the “tubes” are formed by aperture slots in a stacked assembly of flat, low-conduction baffle plates. Because these apertures collimate both incident x-rays and thermal radiation, such an assembly has been termed a “thermal precollimator.” This paper describes precollimator design principles and design, analysis and testing of a precollimator for the Advanced X-ray Astrophysics Facility (AXAF).

Structural durability and ride comfort are two of the main aspects that determine the reliability of a motorcycle. Simulations in the CAE environment are extensively used to carry out those analyses. Jump test and drop test are widely adopted methods used to analyze the off-road capability of motorcycles. For jump test motorcycles run at a constant speed and are made to take a jump from a ramp of a specific height, so that the vehicle will land on wheels with the desired angle of attack after the flight. During the drop test, the vehicle is made to fall from a height that is equal to the maximum height achieved by the vehicle during the jump test flight. Correlation studies are conducted between the jump test and drop test so that the physical test set-up could be evaluated. Simulation of the jump test of a motorcycle is carried out for the suspension assessment, ride comfort and chassis durability analysis.

The National Research Council’s Gas Turbine Laboratory provides industry leading icing facilities that allow manufacturers to develop, validate and certify new products for flight in adverse conditions. This paper shows how NRC measurement techniques are used across the facilities, and presents a literature-review of recently developed capabilities. The overview includes new details on some facilities, and future capabilities that are in development or planned for the near future. Methods developed at the NRC for characterizing inclement conditions are discussed and include the Isokinetic Probe, Particle Shadow Velocimetry, the Particle Detection Probe, and a size-binned real-time thermodynamic evaporation model.

This paper proposes wall function models to simulate the heat transfer around a cylinder in cross flow with an isothermal and rough surface. The selected case has similitudes with aircraft wing icing: the ice roughness shape, height and distribution. Moreover, the flow is somewhat similar to that found on iced airfoil; and the surface is isothermal like when icing. The Reynolds-Averaged Navier-Stokes, turbulence, energy and mass conservation 7-equation system is solved by two Computational Fluid Dynamics (CFD) codes. To represent accurately the effects of roughness on the heat transfer, the present authors had to modify both codes and to propose new thermal wall functions for them. In addition, it was implemented a momentum wall function that is not so common in CFD codes but it is a standard in aircraft icing simulation.

The present paper presents a validation of momentum boundary-layer integral solution and finite-volume Reynolds-Averaged Navier Stokes (RANS) Computational Fluid Dynamics (CFD) results for skin friction around airfoils NACA 8H12 and MMB-V2 as well as heat transfer around an isothermal cylinder with rough surface. The objective is to propose a two-equation integral model and compare its predictions to results from a robust CFD tool, to experimental data and to results from a one-equation integral solution. The latter is the mathematical model used by classic 2D icing codes. All proposed model predictions are compared to CFD results for verification and, whenever possible, to experimental data for validation. The code-to-code verification brings reliability to both the proposed code and the CFD tool when there is no test data available.

The intensive deployment of UAVs for surveillance and reconnaissance missions during the last couple of decades has revealed their vulnerability to icing conditions. At present, a common icing avoidance strategy is simply not to fly when icing is forecast. Consequently, UAV missions in cold seasons and cold regions can be delayed for days when icing conditions persist. While this approach limits substantially the failure of UAV missions as a result of icing, there is obviously a need to develop all-weather capabilities. A key step in accomplishing this objective is to understand better the influence of a smaller geometry and a lower speed on the ice accretion process, relative to the extensively researched area of in-flight icing for traditional aircraft configurations characterized by high Reynolds number. Our analysis of the influence of Reynolds number on the ice accretion process is performed for the NACA0012 airfoil.

Nautilus S.p.A. and the Polytechnic of Turin, in cooperation with Blue Engineering, have developed a very versatile product, the ELETTRA Twin Flyers [6] (ETF), which consists in a very innovative remotely-piloted airship equipped with high precision sensors and communication devices. This multipurpose platform is particularly suitable for border and maritime surveillance missions and for telecommunication, both in military and civil area. To assess the actual maneuver capabilities of the airship [14], a prototype of reduced size and complexity has been assembled [16]. Before the flight tests a further assessment on the flight simulator is needed, because the first version of the software is tuned on the full scale prototype. Steady state performance and static stability of the demonstrator have been evaluated with CFD analysis.

Within NASA's Aviation Safety Program, the Aviation System Monitoring and Modeling (ASMM) Project addresses the need to provide decision makers with the tools to identify and evaluate predisposing conditions that could lead to accidents. This Project is developing a set of automated tools to facilitate efficient, comprehensive, and accurate analyses of data collected in large, heterogeneous databases throughout the National Aviation System. This report is a brief overview of the ASMM Project as an introduction to the rest of the presentations in this session on one of its key elements---the Performance Data Analysis and Reporting System (PDARS).

Oven and flame tests were designed and conducted to evaluate the heat resistance of a ceramic coating material, Cerakote C-7700Q, and evaluate its viability to replace the intumescent coating as one painting material for helicopter engine cowlings. The test results showed that the currently used painting scheme of the engine cowlings failed the 220°C oven test while after replacing the epoxy seal coat with the Cerakote, the new painting system passed the 220°C test in regards to painting bubbling. This study explained why serious appearance defects occurred in the inner skin of the engine cowling when the aircraft is hovering and suggested that one most time- and cost-effective solution is to repaint the current engine cowlings with a new three coating system of Cerakote, surface protection HS7072-622, and intumescent paint as a fireproof lacquer.

Traditional in-flight entertainment systems have evolved from basic audio and video sources into true network-based information systems onboard commercial aircraft. As these systems improve speed, capacity, and bandwidth, connectivity with passenger devices is feasible and now being implemented, although only at a level of service local to the aircraft. Customer expectations have evolved as well, driving the need to interface with various laptop, PDA, and cellular devices. What remains is for commercial aviation suppliers to bridge the connectivity gap between the aircraft and ground networks, so that broadband interface with the Internet can be realized. Significant technical challenges from both communications networks and aircraft engineering must be overcome. Compounding the existing stringent aircraft regulatory issues will be newly developed requirements from the FCC and foreign authorities.

This paper will describe the commercial drivers and a new technical solution for providing Satellite TV to moving vehicles in a form factor and at a price point that will allow for application to virtually any size vehicle. The paper will further describe a new video delivery service concept (tentatively described as T7 for the purpose of the paper) that will provide a fast to market, low capital expenditure, and fully scalable platform specifically designed for use in mobile vehicle applications.

The future car cockpit features individual personal information, communication and entertainment for the driver and the passenger. The user interface and the functionality are optimized with respect to minimum driver distraction, intuitive and ergonomic use, and appealing design. Navigation and entertainment will be wirelessly connected to internet services. The user will find a functionality, menu logic and graphics similar to consumer electronics and internet applications, adapted to automotive usage. Large displays and a new graphics design style create a unique selling point and will replace the classic instrumentation in dedicated market segments. Speech dialog will become more performing and intuitively, and the remote use of mobile devices becomes seamless and convenient. The infotainment architecture is modular and scaleable, and builds upon standard hardware and software components from the IT industry.

XM Satellite Radio launched its nationwide service in September of 2001. With 6.5 million subscribers at the end of the first quarter of 2006, XM is one of the fastest growing audio formats and entertainment services. This paper addresses XM's technology and content evolution, primarily for the radio unit and the signaling protocols, from the early years to the present time, and the applicability of this technology in fostering exciting new infotainment services. The radio architecture includes an antenna, an RF tuner module, a baseband chipset and a microprocessor. All of these subsystems underwent a complete transformation in the past four years from a size perspective, capability and cost. Specifically the following phases of the radio platform are addressed: a) Phase 1: The early years; b) Phase 2: The invention of the Plug and Play ; c) Phase 3: Connect and Play ; d) Phase 4; The wearable; e) Phase 5: Infotainment convergence of audio plus data services.

Strawberry is a life-support-system candidate crop species that is long-lived, asexually propagated, and can bear large quantities of fruit high in sugar and antioxidant content. Strawberries of four day-neutral cultivars (‘Tribute’, ‘Tristar’, ‘Seascape’, and ‘Fern’) and one ever-bearing cultivar (‘Cavendish’) were grown under greenhouse conditions or varying temperature regimes in three growth chambers. Flowers in growth chambers were hand pollinated three-times weekly with stored pollen, and ripe berries were harvested, counted, weighed, and tested organolepticly. In the greenhouse, two different pollination treatments were compared, while another group of plants was left unpollinated, receiving only occasional mechanical stimulation from normal greenhouse airflow, berry harvest, and plant maintenance. A second group was pollinated with a vibrating wand, and a third group was hand pollinated with stored pollen.

Certification of climb performance has traditionally been accomplished using reciprocal heading climbs. This was done to eliminate wind gradient effects. However, the FAA allows climb certification to be done on a single heading when inertial methods are used. A method was developed utilizing a DGPS system that allows an engineer to apply the inertial corrections to a single climb without the need of INS equipment. This method has been validated on several aircraft by comparing conventional reciprocal heading climb results to results obtained using the GPS method on the same climbs. The GPS climb method presented here can potentially reduce the number of climbs required for development and certification as well as provide more consistent data.

Component deviations between as-designed and as-built as a result of deformations in the production process lead to significant cost increasing during assembly. After quality inspection, components are provisionally preassembled to determine their matching accuracy. Components with an acceptable tolerance range are then assembled. Otherwise costly reworks are required. Subsequently, the preassembly process is repeated until acceptable assembly tolerances are achieved. To avoid this time-consuming and costly process loop, a flexible mounting frame coupled with a real-time measuring system is used to optimize the assembly process. The flexible mounting frame can be applied for many applications where components are to be aligned and mounted. This flexible mounting frame allows the realization of exact shape and acceptable position tolerances. The mounting frame consists of telescopic carbon fiber reinforced polymer (CFRP) tubes, linear actuators and suctions grippers.

The Weapon Combat Effectiveness (WCE) analytics is very expensive, time-consuming, and dangerous in the real world because we have to create data from the real operations with a lot of people and weapons in the actual environment. The Modeling and Simulation (M&S) of many techniques are used for overcoming these limitations. Although the era of big data has emerged and achieved a great deal of success in a variety of fields, most of WCE research using the Defense Modeling and Simulation (DM&S) techniques studied have considered a lot of assumptions and limited scenarios without the help of big data technologies. Furthermore, WCE analytics using previous methodologies cannot help but get the bias results. This paper reviews and combines the basic knowledge for the new WCE analytics methodology using big data and M&S to overcome these problems of bias. Then this paper reviews the general overview of WCE, DM&S, and big data.

Every now and then a good idea happens. The Modular head was a great idea and enabled the use of multiple types of AFP heads, ATL, ply cutting, part probing, etc. with the use of a single machine and machining cell. At the time the modular head was developed by Electroimpact circa 2004, the industry assumed (and accepted) that AFP was an unreliable process. It still isn’t as reliable as we’d like. One way of coping with this lack of reliability is to stage more than one head in the AFP cell so that a spare head of the exact same type is ready to jump into action if the head out on the floor has an issue. If the reliability of the AFP process were to increase 10x or 50x, would there still be a business case for the multiple AFP head system? The modular head may still win the day, but the metrics change. For instance, if there was only 20 minutes of down time for every head load, it may no longer be advantageous to have 2 heads of the exact same type in the cell.

This paper introduces a data driven model for predicting airport arrival capacity with 2-8 hour look-ahead forecast data. The model is suitable for air traffic flow management by explicitly investigating the impact of convective weather on airport arrival meter fix throughput. Estimation of the arrival airport capacity under arrival meter fix flow constraints due to severe weather is an important part of Air Traffic Management (ATM). Airport arrival capacity can be reduced if one or more airport arrival meter fixes are partially or completely blocked by convective weather. When the predicted airport arrival demands exceed the predicted available airport’s arrival capacity for a sustained period, Ground Delay Program (GDP) operations will be triggered by ATM system.

An Airbus methodology for the assessment of accurate hydraulic performance at early program stages in the complete aircraft and power consuming systems environment based on joint collaboration with Chiastek is presented. The aim is to comfort the prediction of an aircraft hydraulic performance in order to limit the need for a physical integration test bench and extensive flight test campaign but also to avoid late system redesign based on robust early stage model based engineering and to secure the aircraft entry-into-service.