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In the design of solar powered cars aerodynamic efficiency is extremely important. Due to the limited power and energy sources available, the aerodynamic design of the car must provide a low coefficient of drag. In order to identify the major drag source areas in the design and to improve the aerodynamics performance of the current NDSU solar car an extensive computational fluid dynamics (CFD) study was performed using ANSYS CFX 10.0. The study was set into two paths. The first path focused on modifying the current NDSU solar car design in order to reduce the drag force. The second path was to design a completely new solar car with better aerodynamics performance. Through the CFD analysis of all the designs considered major drag source areas were identified as the underbody, the dome, and the nose section of the car.

A CFD method for predicting wear and heat transfer for an aircraft skid is described. It uses a finite volume method with a moving grid to account for wear. Therefore the skid material flows through the grid. The interface between the skid and runway is modeled empirically and is based on test data. A calculation for a simple skid is presented. The code is written in Mathematica which runs quickly and therefore is useful for experimenting with physical models and conducting trade studies.

Tailsitter UAVs with their combined vertical take off and landing (VTOL) and fixed-wing aircraft with full flight-speed regime capability provides a distinct alternative to rotary-wing and ducted fan UAVs (OAVs). ITU-BYU Tailsitter concept aims to obtain the energy efficient regimes across the VTOL and the cruising flight regimes. This paper describes the hybrid propulsion system design approach to attain this. The preliminary design and the analysis indicate advantageous performance over other mini-class unmanned air vehicles.

A novel method of piloting control removes the requirements of conventional operator control mechanisms to facilitate simplified incorporation of a motorcycle and a separable flight device. The operator uses a single handlebar to concurrently and independently affect the three axis of fixed-wing flight. Pitch, roll, and yaw, are affected through movements of up/down, tilt, and rotation respectively. The yaw rotation is also associated with ground steering. The resulting product, a flight and motor module fastened to a lightly modified commercially-acquired motorcycle, is cost accessible to an un-before tapped market segment.

The work attains a new hybrid concept of a light unmanned aerial vehicle, called “Nimbus”, based on an inflatable lifting body which combines the characteristics and the performances of Lighter-Than-Air and Heavy-Than-Air platforms. This hybrid design allows short take off and landing (STOL) capability due to its low wing loading, absolute stability reference, good employable payload capacity, high endurance, no runway or ground handling system requirements and easy piloting. The inflatable wing is a cylindrical pneumatic chamber, light weight, V shaped and filled with helium. The main aim of the paper is to describe the approach followed in the preliminary design of the Nimbus platform supported by evidences provided by both CFD simulations and experimental trials of a model prototype. The numerical simulations are performed in order to characterize the near flow field on the blimp lifting body balloon and to estimate the main performances of the aerial vehicle.

TU Delft in the Netherlands is performing research into the effects of the use of synthetic kerosene in aircraft. The research program consists of both desk research and tests. In the desk research gas turbine simulations will be combined with payload range performance calculations to show engine effects and fuel consumption changes. Ground and flight tests will be performed to show safe operation on synthetic fuel and to validate the calculations. Measurements during the ground tests will show the changed emissions as a result of the synthetic fuel.

The present paper investigates the effectiveness of dielectric barrier discharge plasma actuators for use as micro thrusters in micro and nano aerial vehicles (μAVs and nAVs). For these small scale vehicles, the range of Re is very small and the subsequent aerodynamics are in a region of relatively unknown physics. Development of suitable propulsion systems involve the integration of a reliable power source with sufficient energy and power density to carry out a mission. The propulsion system must be capable of demonstrating highly efficient conversion of stored energy to thrust to propel the vehicle in both hover and forward flight. Thus, highly efficient actuators are required for micro and nano air vehicle designs. This configuration consists of a closed circumferential arrangement which yields a body force when a voltage difference is applied across the inner and outer electrodes.

In the last few years, the Robotics Division of ABB Inc. has made some key contributions to the high performance robotic paint finishing technology. The developments have been predominantly motivated by the applications required for the automotive industry, but they are still highly applicable to aerospace applications, both for aircraft assembly and part manufacturing. These developments include: new IRB5500 robots with increased work envelope and acceleration capability; highly efficient RB1000 paint atomizer family; CBS advanced paint saving cartridge technology; new robotic powder paint application (IC-3) and color change (PCC) equipment; DispensePac sealant and adhesive robotic dispensing systems including newest applications of sprayable masking materials; TrueView vision and force control systems supporting applications in work object location, robot guidance, part cleaning, sanding, polishing and masking.

This paper aims to derive a comprehensive dynamical model and analysis of a High-Altitude-Long-Endurance (HALE) Unmanned Aerial Vehicles (UAVs). Structure of such an aircraft needs to be lightweight and capable of carrying a substantial payload. For low drag, the aircraft must have high aspect ratio. Moreover, safety factors for these aircraft are not as high as those for manned aircraft. These imply that HALE UAVs are considerably more flexible than manned aircraft. Hence, in the dynamical analysis of such aircraft, a formulation unifying the elastic and rigid body motions of the aircraft must be used. A newly developed theory for the dynamics of maneuvering flexible aircraft is ideally suited for the analysis of such aircraft. The uniqueness of this paper lies in its nonlinear structural model. The equations of motion are obtained by means of the Lagrangian equations in quasicoordinates. A perturbation approach separates the problem into nominal dynamics and perturbation dynamics.

Very Light Jets (VLJ)1 could very well revolutionize regional air travel around the world for both business and pleasure by providing an affordable alternative for thousands of owner/pilots, small companies, and potential customers of on-demand air services. Unfortunately, there are also concerns that the VLJ may experience a surge of early deliveries and rapid growth followed by a series of tragic and preventable human-caused accidents. Many international aviation professionals feel that, in order to ensure VLJ operational safety, stakeholders must cause manufacturers, insurers, and regulators to address key questions about proposed VLJ training programs and their related human factors issues.

This technical paper presents the author’s recommended approach to one aspect of managing flight safety - conducting Safety Risk Analyses (SRA) on in-service problems that may threaten flight safety. The author did not develop this statistically based approach for assessing the risk of future events, but has helped to improve it and highly endorses it. In conducting a safety risk analysis, the analyst might decide to perform a “quick” SRA and will need a minimal amount of information that will show the relative level of flight safety risk. When the analyst decides a complete safety risk analysis is needed, the possible approaches and level of details included in the SRA can vary greatly from company to company.

The necessity of avoiding the destructive and non-repeatable FSST (Full Scale Sled Test) makes it desirable to devise a cheaper and more repeatable method which can supplant this test procedure. This need developed the HCTD (HIC Component Testing Device) which is capable of providing conservative HIC results with higher repeatability. The computational model of the HCTD is validated against one of the tests conducted at CAMI with polyethylene foam. This validated model is used to conduct a series of tests with input parameters similar to the sled test to develop the correlation between the sled test and HCTD. This study hence concludes that a validated computational model of HCTD can be successfully utilized to address the HIC compliance issues for a foam padded surface.

The high cost, lengthy time, and lack of synergistic integration activities between aircraft based on the current aircraft/store integration process have driven domestic and foreign militaries to search for a plug-and-play approach for aircraft/store integration. In order to integrate the increasingly complex, software-intensive systems that are currently being designed, streamlined processes must be developed to facilitate their timely adoption. One of the most promising approaches is Model-Driven Engineering (MDE) and Model Driven Architecture (MDA). MDE allows designers to use high-level models to solve particular design problems. With MDE, the systems architecture can be analyzed through many different views and then MDA can be used to transform these high-level models to usable software through an automatic code generation process.

Inflatable wings have proven themselves to be a viable option in unmanned aerial vehicle (UAV) flight in certain applications. There are several advantages when using inflatable wings. Foremost among these is the ability of the aircraft to be stored, fully assembled, in a smaller volume for ease of transportation and quick launch capability. Example applications currently being pursued include backpackable UAVs and extra-terrestrial aircraft, as well as HALE UAVs deployed from rapid delivery systems. This paper discusses the design options between using a folding wing system that is volume limited and an inflatable wing system that is mass limited. There should be an optimum between the two that provides the lowest packed volume and weight combination for the highest deployed span. The concept of hybrid rigid/inflatable wings appears to be feasible for UAVs that combine both systems.

This paper describes a unique partnership between NASA and students residing in the Texas Rio Grande Valley. The program is based on annual activities that provide a connection between NASA and border communities via mentoring. The approach utilizes older students and teachers as mentoring ambassadors who are trained at NASA Johnson Space Center in Houston. The mentors are trained in specific space themes for each year's main event and return to South Texas to serve as mentors and role models for younger students. The main event occurs at UT Brownsville, in which over 600 5th and 8th graders from five counties attend. The event utilizes the trained ambassadors to offer more than 20 hands-on activities that highlight a theme related to NASA's current focus and missions. The activities demonstrate how math, science, and engineering relate to exploring and understanding the universe and solving problems on earth.

Data obtained from digital flight data recorders are used to assess the actual operational environment of propellers on a fleet of Beech 1900D aircraft in commuter role. Information is given on various aerodynamic parameters as well as those pertaining to engine and propeller usage. The takeoff rotation has been identified as the most demanding phase of flight in terms of unsteady loads exerted on the propeller blades. Special attention is paid to ground operations.

Global warming concerns have prompted actions to restrict carbon dioxide emissions by a rapidly growing number of nations throughout the world. The aviation community can expect emission limits in the near future, and should become pro-active in this arena. Rapid advances are being made in the automobile industry to research and develop more efficient vehicles. The very successful introduction of gasoline-electric hybrid automobiles has spawned intense research and development of advanced batteries, ultra-capacitors, electric motors and controls. Opportunities for adapting automobile technologies to small general aviation airplanes should be exploited. Over the past few years, several groups have successfully flown experimental airplanes powered by ground-rechargeable batteries.

Liquid Chromatography / Mass Spectrometry / Mass Spectrometry (LC/MS/MS) is a powerful technique for identifying unknown non-volatile organic compounds dissolved in liquids. One type of LC/MS/MS that is gaining popularity is quadrupole-time-of-flight (QqTOF) mass spectrometry. This technique is now in use at the Johnson Space Center for identification of unknown nonvolatile organics in water samples from the space program. An example of the successful identification of an unknown peak in U.S. Lab Condensate is reviewed in detail in this paper. Each step of the procedure is described in the identification of triethylene glycol mono-n-butyl ether (TGBE) as the unknown analyte. The advantages of time-of-flight instrumentation are demonstrated through this example as well as the strategy employed in using time-of-flight data to identify unknowns. The use of the instrument for quantitative analysis is also demonstrated.

Water quality standards have been completed for space vehicles and habitats for ingestion periods from 1 day to 1000 days. These standards are called spacecraft water exposure guidelines (SWEGs). The National Research Council Committee on Toxicology has worked with the Toxicology Group at the National Aeronautics and Space Administration (NASA) to set and document these standards. Prior to SWEG development, the practice of NASA was to apply the United States Environmental Protection Agency (USEPA) maximum contaminant levels (MCLs) in the interpretation of any potential health effects from water pollutants. This practice had the potential to result in erroneous conclusions because MCLs are intended for lifetime exposures and are set to protect a much more diverse population than is present in the astronaut corps. However, for certain pollutants it was recognized that the stresses of spaceflight may make astronauts more susceptible to adverse effects.