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Articles 571 - 600 of 682

Full-Text Articles in Aviation

Adopting A Kinetic Energy Recovery System For Helicopters, Nihad E. Daidzic Sep 2013

Adopting A Kinetic Energy Recovery System For Helicopters, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.


T/O Overruns And Veer-Offs On Slippery Runways With Crosswinds, Nihad E. Daidzic Aug 2013

T/O Overruns And Veer-Offs On Slippery Runways With Crosswinds, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.


Reducing Uncertainty In Fatigue Life Limits Of Turbine Engine Alloys, J M. Larson, S K. Jha, C J. Szczepanski, M J. Caton, R John, A H. Rosenberger, D J. Buchanan, P J. Golden, J R. Jira Jan 2013

Reducing Uncertainty In Fatigue Life Limits Of Turbine Engine Alloys, J M. Larson, S K. Jha, C J. Szczepanski, M J. Caton, R John, A H. Rosenberger, D J. Buchanan, P J. Golden, J R. Jira

United States Air Force: Publications

In probabilistic design of materials for fracture-critical components in modern military turbine engines, a typical maximum design target risk (DTR) is 5 X 10-8 component failures/engine flight hour. This metric underscores the essential role of safety in a design process that simultaneously strives to achieve performance, efficiency, reliability, and affordability throughout the life cycle of the engine. Traditionally, the design and life management approaches for engine materials have typically relied on extensive testing programs to produce large databases of fatigue data, from which statistically based life limits are derived by extrapolation from the mean fatigue behavior. However, we …


Stability And Power Optimality In Time-Periodic Flapping Wing Structures, Bret Stanford, Philip Beran, Richard Snyder, Mayuresh Patil Jan 2013

Stability And Power Optimality In Time-Periodic Flapping Wing Structures, Bret Stanford, Philip Beran, Richard Snyder, Mayuresh Patil

United States Air Force: Publications

This paper investigates the nonlinear dynamics of a vehicle with two flexible flapping wings. The body dynamics and the wings' deformation are monolithically grouped into a single system of equations, with aerodynamics accounted for by a quasi-steady blade element method. A periodic shooting method is then used to locate closed orbits of this non-autonomous system, and Floquet multipliers assess the linearized stability about the nonlinear orbit. This framework is then exposed to a gradient based optimizer, in order to quantify the role of wing planform variables, wing structure variables, and kinematic actuation variables in obtaining vehicles with superior open-loop stability …


Direct Flutter And Limit Cycle Computations Of Highly Flexible Wings For Efficient Analysis And Optimization, Bret Stanford, Philip Beran Jan 2013

Direct Flutter And Limit Cycle Computations Of Highly Flexible Wings For Efficient Analysis And Optimization, Bret Stanford, Philip Beran

United States Air Force: Publications

The usefulness of flutter as a design metric is diluted for wings with destabilizing (softening) nonlinearities, as a stable high-amplitude limit cycle (subcritical) may exist for flight speeds well below the flutter point. It is thus desired to design aeroelastic structures such that the post-flutter behavior is as benign (i.e., supercritical) as possible, among the other constraints commonly considered in the optimization process. In order to account for these metrics in an accurate and efficient manner, direct tools are utilized to first locate the Hopf-point (flutter speed), and then to obtain a nonlinear perturbation solution via the method of multiple …


Direct Ignition And S-Curve Transition By In Situ Nano-Second Pulsed Discharge In Methane/Oxygen/Helium Counterflow Flame, Wenting Sun, Sang Hee Won, Timothy Ombrello, Campbell Carter, Yiguang Ju Jan 2013

Direct Ignition And S-Curve Transition By In Situ Nano-Second Pulsed Discharge In Methane/Oxygen/Helium Counterflow Flame, Wenting Sun, Sang Hee Won, Timothy Ombrello, Campbell Carter, Yiguang Ju

United States Air Force: Publications

A well-defined plasma assisted combustion system with novel in situ discharge in a counterflow diffusion flame was developed to study the direct coupling kinetic effect of non-equilibrium plasma on flame ignition and extinction. A uniform discharge was generated between the burner nozzles by placing porous metal electrodes at the nozzle exits. The ignition and extinction characteristics of CH4/O2/He diffusion flames were investigated by measuring excited OH* and OH PLIF, at constant strain rates and O2 mole fraction on the oxidizer side while changing the fuel mole fraction. It was found that ignition and extinction occurred with an abrupt change of …


The Potential Costs To The Dod Of Not Preparing For The Nextgen Nas Overhaul: Lessons Learned From Rvsm, Casey Richardson Jan 2013

The Potential Costs To The Dod Of Not Preparing For The Nextgen Nas Overhaul: Lessons Learned From Rvsm, Casey Richardson

Graduate Student Works

In order to facilitate a significant overhaul of the civilian National Airspace System (NAS), the Federal Aviation Administration (FAA) has partnered with many federal agencies, such as the departments of Transportation (DOT), Defense (DoD), Homeland Security (DHS), and Commerce (DOC) and the National Aeronautics & Space Administration (NASA) through a consolidated Joint Planning and Development Office (JPDO) that was established by Congress in 2003 in the VISION 100 – Century of Aviation Reauthorization Act (JPDO, 2012). The JPDO has proposed replacing the old NAS structure of primarily ground-based navigation with robust satellite-enabled air traffic procedures and to supplement ground-based air …


Indeterminate Masses, Elements And Models In Information Fusion, Florentin Smarandache Jan 2013

Indeterminate Masses, Elements And Models In Information Fusion, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In this paper at the beginning, we make a short history of the logics, from the classical Boolean logic to the most general logic of today neutrosophic logic. We define the general logic space and give the definition of the neutrosophic logic. Then we introduce the indeterminate models in information fusion, which are due either to the existence of some indeterminate elements in the fusion space or to some indeterminate masses.

The best approach for dealing with such models is the neutrosophic logic, which is part of neutrosophy. Neutrosophic logic is connected with neutrosophic set and neutrosophic probability and statistics.


Development Of A Master Of Software Assurance Reference Curriculum, Andrew J. Kornecki, James Mcdonald, Julia H. Allen, Mark Ardis, Nancy Mead, Richard Linger, Thomas B. Hilburn Jan 2013

Development Of A Master Of Software Assurance Reference Curriculum, Andrew J. Kornecki, James Mcdonald, Julia H. Allen, Mark Ardis, Nancy Mead, Richard Linger, Thomas B. Hilburn

Department of Electrical Engineering and Computer Science - Daytona Beach

The Next Generation Air Traffic Management system (NextGen) is a blueprint of the future National Airspace System. Supporting NextGen is a nation-wide Aviation Simulation Network (ASN), which allows integration of a variety of real-time simulations to facilitate development and validation of the NextGen software by simulating a wide range of operational scenarios. The ASN system is an environment, including both simulated and human-in-the-loop real-life components (pilots and air traffic controllers).Real Time Distributed Simulation (RTDS) developed at Embry-Riddle Aeronautical University, a suite of applications providing low and medium fidelity en-route simulation capabilities, is one of the simulations contributing to the ASN. …


Fault Tree Analysis For Safety/Security Verification In Aviation Software, Andrew J. Kornecki, Mingye Liu Jan 2013

Fault Tree Analysis For Safety/Security Verification In Aviation Software, Andrew J. Kornecki, Mingye Liu

Department of Electrical Engineering and Computer Science - Daytona Beach

The Next Generation Air Traffic Management system (NextGen) is a blueprint of the future National Airspace System. Supporting NextGen is a nation-wide Aviation Simulation Network (ASN), which allows integration of a variety of real-time simulations to facilitate development and validation of the NextGen software by simulating a wide range of operational scenarios. The ASN system is an environment, including both simulated and human-in-the-loop real-life components (pilots and air traffic controllers).Real Time Distributed Simulation (RTDS) developed at Embry-Riddle Aeronautical University, a suite of applications providing low and medium fidelity en-route simulation capabilities, is one of the simulations contributing to the ASN. …


A Gap Analysis Of Meteorological Requirements For Commercial Space Operators, Nicholas J. Stapleton Nov 2012

A Gap Analysis Of Meteorological Requirements For Commercial Space Operators, Nicholas J. Stapleton

Doctoral Dissertations and Master's Theses

Commercial space companies will soon be the primary method of launching people and supplies into orbit. Among the critical aspects of space launches are the meteorological concerns. Laws and regulations pertaining to meteorological considerations have been created to ensure the safety of the space industry and those living around spaceports; but, are they adequate? Perhaps the commercial space industry can turn to the commercial aviation industry to help answer that question. Throughout its history, the aviation industry has dealt with lessons learned from mishaps due to failures in understanding the significance of weather impacts on operations. Using lessons from the …


Acoustic Emission Signal Classification For Gearbox Failure Detection, Jun Shishino Oct 2012

Acoustic Emission Signal Classification For Gearbox Failure Detection, Jun Shishino

Doctoral Dissertations and Master's Theses

The purpose of this research is to develop a methodology and technique to determine the optimal number of clusters in acoustic emission (AE) data obtained from a ground test stand of a rotating H-60 helicopter tail gearbox by using mathematical algorithms and visual inspection. Signs of fatigue crack growth were observed from the AE signals acquired from the result of the optimal number of clusters in a data set. Previous researches have determined the number of clusters by visually inspecting the AE plots from number of iterations. This research is focused on finding the optimal number of clusters in the …


A (Declassified) History Of Military Drones, Stephen Rayleigh Sep 2012

A (Declassified) History Of Military Drones, Stephen Rayleigh

ERAU Prescott Aviation History Program

Unmanned Aerial Vehicles or drones, are said to be the newest technology of contemporary warfare, but the military's use of drones spans the last 100 years. Hear the riveting story of the numerous secret UAV programs around the world, starting with the Sperry Aerial Torpedo Project in 1918 (consulted by Orville Wright), the German cruise missile program, American remote controlled bombers in WWII, the Firebee recon drone used in Vietnam, Israel's highly successful UAV program, and finally the coming of age of UAV's in Operation Desert Storm.


Jet Engine Thrust Ratings, Nihad E. Daidzic Sep 2012

Jet Engine Thrust Ratings, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.


Extended Pcr Rules For Dynamic Frames, Florentin Smarandache, Jean Dezert Jul 2012

Extended Pcr Rules For Dynamic Frames, Florentin Smarandache, Jean Dezert

Branch Mathematics and Statistics Faculty and Staff Publications

In most of classical fusion problems modeled from belief functions, the frame of discernment is considered as static. This means that the set of elements in the frame and the underlying integrity constraints of the frame are fixed forever and they do not change with time. In some applications, like in target tracking for example, the use of such invariant frame is not very appropriate because it can truly change with time. So it is necessary to adapt the Proportional Conflict Redistribution fusion rules (PCR5 and PCR6) for working with dynamical frames. In this paper, we propose an extension of …


Spacecraft And Propulsion Technician Error, Daniel Clyde Schultz May 2012

Spacecraft And Propulsion Technician Error, Daniel Clyde Schultz

Doctoral Dissertations and Master's Theses

Commercial aviation and commercial space similarly launch, fly, and land passenger vehicles. Unlike aviation, the U.S. government has not established maintenance policies for commercial space. This study conducted a mixed methods review of 610 U.S. space launches from 1984 through 2011, which included 31 failures. An analysis of the failure causal factors showed that human error accounted for 76% of those failures, which included workmanship error accounting for 29% of the failures. With the imminent future of commercial space travel, the increased potential for the loss of human life demands that changes be made to the standardized procedures, training, and …


Fadec Advances Allow Better Engine Performance, Nihad E. Daidzic Mar 2012

Fadec Advances Allow Better Engine Performance, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.


A Systematic Approach For Real-Time Operator Functional State Assessment, Guangfan Zhang, Wei Wang, Aaron Pepe, Roger Xu, Tom Schnell, Nick Anderson, Dean Heitkamp, Jiang Li, Feng Li, Frederick Mckenzie Jan 2012

A Systematic Approach For Real-Time Operator Functional State Assessment, Guangfan Zhang, Wei Wang, Aaron Pepe, Roger Xu, Tom Schnell, Nick Anderson, Dean Heitkamp, Jiang Li, Feng Li, Frederick Mckenzie

Electrical & Computer Engineering Faculty Publications

A task overload condition often leads to high stress for an operator, causing performance degradation and possibly disastrous consequences. Just as dangerous, with automated flight systems, an operator may experience a task underload condition (during the en-route flight phase, for example), becoming easily bored and finding it difficult to maintain sustained attention. When an unexpected event occurs, either internal or external to the automated system, the disengaged operator may neglect, misunderstand, or respond slowly/inappropriately to the situation. In this paper, we discuss an approach for Operator Functional State (OFS) monitoring in a typical aviation environment. A systematic ground truth finding …


The Propulsive Design Aspects On The World’S First Direct Drive Hybrid Airplane, Ankit Nanda Oct 2011

The Propulsive Design Aspects On The World’S First Direct Drive Hybrid Airplane, Ankit Nanda

Doctoral Dissertations and Master's Theses

The purpose of this thesis is to design a safe technology demonstrator by implementing a direct drive propulsion system for a gas-electric hybrid aircraft. This system was integrated on the Embry-Riddle Eco-Eagle for the Green Flight Challenge 2011. The aim of the system is to allow the pilot to use the electric motor as an independent power source to fly the aircraft once at cruise altitude, while having a gas engine to allow for higher power capability.

The system was designed to incorporate the motor and the motor control unit provided by Flight Design and Drivetek AG alongside a Rotax …


Integration Of Unmanned Aerial Systems In Class E Airspace: The Effect On Air Traffic Controller Workload, Jeeja S. Vengal Oct 2011

Integration Of Unmanned Aerial Systems In Class E Airspace: The Effect On Air Traffic Controller Workload, Jeeja S. Vengal

Doctoral Dissertations and Master's Theses

As technology rapidly advances and our imagination is no longer fantasy but instead reality, the aviation community needs to concentrate on the harsh truth of airspace safety. In the situation of integrating unmanned aerial systems (UASs) into the National airspace, UASs outside of terminal areas would generally be permitted to fly their preferred routes, and self-separate, with minimal intervention from air traffic control. From an air traffic control perspective, the integration could raise a number of human performance problems including workload extremes and passive-monitoring demands. One fundamental requirement for operation in the National Air Space is to preserve the safety …


Airplane Landing Flare-The Last 5 Seconds, Nihad E. Daidzic May 2011

Airplane Landing Flare-The Last 5 Seconds, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.


Some Considerations For Regional Airline Operations On Contaminated Runways., Nihad E. Daidzic Apr 2011

Some Considerations For Regional Airline Operations On Contaminated Runways., Nihad E. Daidzic

Aviation Department Publications

No abstract provided.


Guidance, Navigation And Control Of A Fly-By-Wire Transport Category Airship Designed For Hover Cargo Delivery, Harshad H. Lalan Apr 2011

Guidance, Navigation And Control Of A Fly-By-Wire Transport Category Airship Designed For Hover Cargo Delivery, Harshad H. Lalan

Master's Theses - Daytona Beach

The purpose of this thesis is to develop fly-by-wire pilot controls for a transport category airship propelled with six thrust vectoring engines, and to develop control laws to maintain position, heading, and attitude during hover and cargo operations. Owing to the large body area, most airships require that they be pointed into the wind to maintain their position. This research aims at controlling an airship attitude and position during hover cargo delivery, irrespective of the wind direction.

Control laws were developed for two primary modes of the airship: Flight (High Speed Mode) and Hover (Cargo Delivery Mode). Different sets of …


Potential Environmental Benefits Of Extending Aircraft Pushback Operations, Dennis R. O'Connell Apr 2011

Potential Environmental Benefits Of Extending Aircraft Pushback Operations, Dennis R. O'Connell

Mechanical & Aerospace Engineering Theses & Dissertations

This study considered extending the operational use of pushback tractors to perform taxi-out airport ground operations for commercial aircraft as an alternative to using aircraft power plants for this operation. Pushback tractors are designed to reverse aircraft from the terminal gate to a position where the aircraft can taxi independently to the departure runway. In this investigation the process of pushback would be extended to pulling the aircraft to the departure runway then returning the pushback tractor to the terminal of origin, a new procedure known as extended pushback.

Data from major aircraft operators and engine manufacturers were collected to …


Dealing With Contaminated Runways, Nihad E. Daidzic Feb 2011

Dealing With Contaminated Runways, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.


Flying Uav’S In Iraq, Stephen Rayleigh Jan 2011

Flying Uav’S In Iraq, Stephen Rayleigh

ERAU Prescott Aviation History Program

Unmanned Aerial Vehicles, or UAV’s, are a growing reality and an important new weapon for today’s military. Hear what it was like to fly the RQ-7B “Shadow” UAV during Operation Iraqi Freedom from Stephen Rayleigh who spent a year in Iraq and has more than 1,000 hours experience flying them.


A Midsummer Night’S Dream (With Flying Robots), Robin Murphy, Dylan Shell, Amy Guerin, Brittany Duncan, Benjamin Fine, Kevin Pratt, Takis Zourntos Jan 2011

A Midsummer Night’S Dream (With Flying Robots), Robin Murphy, Dylan Shell, Amy Guerin, Brittany Duncan, Benjamin Fine, Kevin Pratt, Takis Zourntos

School of Computing: Faculty Publications

Seven flying robot “fairies” joined human actors in the Texas A&M production of William Shakespeare’s A Midsummer Night’s Dream. The production was a collaboration between the departments of Computer Science and Engineering, Electrical and Computer Engineering, and Theater Arts. The collaboration was motivated by two assertions. First, that the performing arts have principles for creating believable agents that will transfer to robots. Second, the theater is a natural testbed for evaluating the response of untrained human groups (both actors and the audience) to robots interacting with humans in shared spaces, i.e., were believable agents created? The production used two types …


Uniform And Partially Uniform Redistribution Rules, Florentin Smarandache, Jean Dezert Jan 2011

Uniform And Partially Uniform Redistribution Rules, Florentin Smarandache, Jean Dezert

Branch Mathematics and Statistics Faculty and Staff Publications

This paper introduces two new fusion rules for combining quantitative basic belief assignments. These rules although very simple have not been proposed in literature so far and could serve as useful alternatives because of their low computation cost with respect to the recent advanced Proportional Conflict Redistribution rules developed in the DSmT framework.


Evidence Supporting Measure Of Similarity For Reducing The Complexity In Information Fusion, Xinde Li, Jean Dezert, Florentin Smarandache, Xinhan Huang Jan 2011

Evidence Supporting Measure Of Similarity For Reducing The Complexity In Information Fusion, Xinde Li, Jean Dezert, Florentin Smarandache, Xinhan Huang

Branch Mathematics and Statistics Faculty and Staff Publications

This paper proposes a new solution for reducing the number of sources of evidence to be combined in order to diminish the complexity of the fusion process required in some applications where the real-time constraint and strong computing resource limitation are of prime importance. The basic idea consists in selecting, among the whole set of sources of evidence, only the biggest subset of sources which are not too contradicting based on a criterion of Evidence Supporting Measure of Similarity (ESMS) in order to process solely the coherent information received. The ESMS criterion serves actually as a generic tool for outlier …


Estimation Of Air Flow Angles Derived From An Inertial Navigation System, Brett Douglas Mather Oct 2010

Estimation Of Air Flow Angles Derived From An Inertial Navigation System, Brett Douglas Mather

Master's Theses - Daytona Beach

The purpose of this study is to explore the use of an Inertial Navigation System as a primary method for measuring aircraft air flow angles in flight testing. The traditional methods used to measure air flow angles consist of sensors external to the aircraft, such as an air data boom or an angle of attack probe. The advantage of using INS to measure air flow angles would be in the simplicity of the instrumentation. All components could be fixed internally, leaving minimal external modifications to the aircraft necessary for instrumentation. This would reduce costs and instrumentation time and enable air …