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The Wave Disk Engine (WDE) is a novel engine that has the potential for higher efficiency and power density of power-generation systems. A recent version of wave disk engine architecture known as the two-stage WDE has been studied to address existing challenges of an existing WDE. After describing the engine operation, a cold air-standard thermodynamic model supporting the physical phenomena occurring inside the device is introduced to evaluate performance of the engine. The developed model is general and does not depend on the shape of the wave rotor, it can be applied to radial and axial combustion wave rotors integrated with turbomachinery devices. The analysis starts with predicting internal waves propagating inside the channels of the engine and linking various flow states to each other using thermodynamics relationships. The goal is to find analytical expressions of work output and efficiency in terms of known pressure and temperature ratios.

The current position of the two-stroke cycle aircraft engine is described with respect to competitive type powerplants, including a brief historical background and information on some of the latest designs. The two-cycle case is substantiated with arguments and data showing why it should still be considered for the lower power ranges.

Numerous turbofan power-loss events have occurred in high altitude locations in the presence of ice crystals. It is theorized that ice crystals enter the engine core, partially melt in the compressor and then accrete onto stator blade surfaces. This may lead to engine rollback, or shed induced blade damage, surge and/or flameout. The first generation of ice crystal icing predictive models use a single flow field where there is no accretion to calculate particle trajectories and accretion growth rates. Recent work completed at the University of Oxford has created an algorithm to automatically detect the edge of accretion from experimental video data. Using these accretion profiles, numerical simulations were carried out at discrete points in time using a manual meshing process.

Deicing the aircraft using fluid, prior takeoff is mandatory; since a thin layer of ice or snow can compromise the safety. With the same idea, to use anti-icing fluid during a frozen precipitation to protect the aircraft is also essential. Commercialized anti-icing fluids all pass the process of qualification as described in the SAE documents. One of these documents specifies a set of tests that reproduce freezing precipitation to obtain endurance time and then the holdover timetables. The endurance time is determined by visual inspection: when 30% of the plate is covered with frozen contaminants. With the evolution of technology and the venue of new tools, it may simplify the process, and at least confirm the observations. This paper proposed a thermal and visual analysis of the behavior of a Type IV fluid subjected to light freezing rain. During the precipitation, the plate temperature is measured with thermocouples and recorded using a visual camera and an IR camera.

Measurements of lightning-induced transients in typical electrical circuits installed within a small, conventional aluminum airplane fuselage have been made as part of a comprehensive assessment of the effects of direct lightning strikes and high intensity radiated frequency (HIRF) fields on avionic systems installed within small aircraft. These measurements were conducted in support of development of design guidelines for installation and certification of advanced avionics in small aircraft, under a U.S. National Aeronautics and Space Administration (NASA) sponsored Small Business Innovation Research (SBIR) program aimed at developing technology to enable advanced avionic systems to be installed in new small airplanes or to be retrofitted into existing airplanes. This paper presents examples and summaries of lightning-related magnetic fields and resulting induced voltage and current transients within a small 4-place Mooney aluminum fuselage and engine nacelle.

Voice technology provides a potential for alleviating the extremely high visual and manual workload of Army helicopter pilots. Before voice technology can be successfully employed in the cockpit, there are many human factors issues that must be resolved. This paper describes the approach used to identify potential applications of voice technology in an Army helicopter and the emulation of a voice interactive doppler navigation set.

The General Aviation safety record through 1970 is discussed, both statistically and in the non-quantitative sense. Related functions of the cognizant aviation accident investigatory agency, the National Transportation Safety Board, are also reviewed to place the data in proper perspective. Finally, a matrix is provided as an outline for participants in the General Aviation system to assess their own contribution to accident/injury prevention in this most rapidly growing segment of aviation.

In order to formulate policy for the orderly development and use of the nation's navigable air space, federal agencies such as the FAA and the Department of Transportation have launched several programs to determine aviation requirements for the next 10 years. This paper outlines their conclusions concerning airborne activities such as flow control, approach and departure control, wake vortex problems, and operating procedures as well as airport capacity and ground operations. The impact of the FAA's Research and Development Program and the implications of the current fuel shortage and economic situation are also discussed.

This paper reviews research work in the United Kingdom on the objective effects of the sonic boom on humans and structures, and the subjective response of humans. Works in these areas, both before and during the Concorde aircraft's supersonic overflights, is described and appropriate references cited.

For the last several years, the Soviet Union, now the Commonwealth of Independent States (CIS), has offered the RD-170 rocket engine for sale to the West. The RD-170 is the most powerful and most technologically advanced rocket engine in production in the world. However, the U.S. presently has no policy regarding the acquisition of Soviet rocket technology such as the RD-170. In order to develop an effective policy, the U.S. must first determine if an application for RD-170 class engines exists, and then weigh the advantages of acquisition such as reliable and cost effective heavy lift capability versus the disadvantages such as exporting U.S. jobs. There are several possible methods of acquisition, although joint U.S.-CIS production of the RD-170 is the most politically viable as it would create U.S. jobs and support economic reforms in the CIS at the same time.

The U.S. Air Force has special problems and requirements regarding electronic color displays. This paper provides an overview of the ways in which the Air Force uses color displays and discusses associated display design issues. Major emphasis is given to airborne displays. Issues that are covered include luminance, ambient illumination, spectral characteristics of the display, color selection and tolerances, color-code size, formatting, resolution, size, weight, power requirements, and ruggedness.

Information on icing flight tests as conducted by the US Army Aviation Engineering Flight Activity is presented. A quick review is conducted of organizations within the US Army that become involved with icing tests. Icing flight test techniques and hardware are shown and discussed. Natural and artificial icing test results are compared. Results and conclusions from previous icing evaluations are shown. The capabilities and limitations of current techniques and systems are discussed. And finally, the process for establishing an airworthiness qualification allowing Army aircraft to fly into a forecast icing environment is presented.

Human error has been shown to be a major factor influencing U.S. Army aviation and ground safety. This paper reviews human-error-related Army aviation mishap data and trends. It also describes the Army data bases related to safety issues, providing information on the data contents, access, capabilities and applications. Additionally, the paper discusses current Army initiatives toward resolution of human error safety problems.

The U.S. Department of Energy's (DOE) Office of Fossil Energy's (FE) National Energy Technology Laboratory (NETL), in partnership with private industry, educational institutions and national laboratories, is leading the research, development, and demonstration of high efficiency, fuel flexible solid oxide fuel cells (SOFCs) and coal-based SOFC power generation systems for stationary market large central power plants. The FE Fuel Cell Program has four parts under the Solid State Energy Conversion Alliance (SECA): cost reduction, coal-based systems, research and development, and manufacturing. The SECA cost reduction goal is to have SOFCs capable of being manufactured at $400 per kilowatt (kW) by 2010. Concurrently, the scale-up, aggregation, and integration of the technology will progress in parallel leading to prototype validation of megawatt (MW) -class fuel flexible products by 2012 with many opportunities for deployment including FutureGen.

Orbital debris mitigation policy has become outdated, and corporations that have an interest in space commerce have historically underused it. This paper studies the policy aspect of orbital debris mitigation, focusing on debris originating from spent rocket stages and telecommunications satellites. The commercialization of space, in particular the Lower Earth Orbit (LEO) has increasingly drawn the interest of space flight and telecommunications industries. This paper shows how new standards, policies, and regulations could affect industrial practices related to orbital debris mitigation. The formation of new policies will have a significant impact on commercial space industries.

This paper presents the basic test data obtained from tests of a cabin air distribution system in a simulated Space Station U.S. Lab-A module. The cabin air distribution system controls the flow of air in the open space of a Space Station module. In order to meet crew comfort criteria the local velocities for this cabin air are required to be distributed within a specified range with upper and lower limits. Achieving this desired velocity distribution is dependent upon the: (1.) design of the cabin air supply equipment and cabin air return equipment, (2.) total flowrate of air supplied to and subsequently returned from the cabin, and (3.) interactive effects of any other additional air flow streams which enter and exit the cabin. The basic Space Station design for the cabin air supply and air return equipment was used in this test program. Only directional adjustments to vanes in supply air diffusers were made during the test.

A U.S. Laboratory-A (U.S. Lab-A) payload rack has two primary thermal control systems designed for cooling payloads: a water cooling system and a distributed avionics air cooling system. This paper gives an overview of the rack-level thermal control systems available in a U.S.Lab-Arack. This paper also presents an analysis of the existing sensible payload heat removal capability of the laboratory module cooling system. In the U.S. Lab-A, all payload rack locations are configured as per the international Standard Payload Rack (ISPR) configuration. This paper begins with an overview of the ISPR with emphasis on the liquid and air cooling interfaces. An overview of both the liquid and air cooling systems is presented, showing general capability and limitations, payload rack flow control modes and optional payload rack thermal configurations. Performance data showing a sample overall system-level thermal energy balance is presented.

The Department of Defense has made progress in modernizing its procurement of weapon systems. Modernization has identified a need to address Federal and military standards and specifications for parts, materials, and processes that represent many de facto national standards. The aerospace industry is proposing a transition to commercial specifications that meet the needs of Acquisition Reform. This paper reviews the history and benefits of modernization and describes the transition process.