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Control And Stability Of Upper Stage Launch Vehicle With Hybrid Arc-Ignition Attitude Control System, Steven Russell Bennett 2019 Utah State University

Control And Stability Of Upper Stage Launch Vehicle With Hybrid Arc-Ignition Attitude Control System, Steven Russell Bennett

All Graduate Theses and Dissertations

The Utah State University Propulsion Research Laboratory (USUPRL) has recently made significant developments in the area of hybrid rocket systems. This type of propulsion system incorporates a solid fuel and a gas or liquid oxidizer. Hybrid rocket systems are known for their inherent safety, reliability, and restart capability. Over the last several years, the USUPRL has successfully built and tested a hybrid rocket system comprising acrylonitrile butadiene styrene (ABS) plastic and gaseous oxygen (GOX). The system was demonstrated to be fully functional during ground, vacuum, and sub-orbital flight testing. Continuing forward, the USUPRL endeavors to extend the capabilities of this ...


High-Pressure Phase Transformations Under Severe Plastic Deformation By Torsion In Rotational Anvils, Valery I. Levitas 2019 Iowa State University and Ames Laboratory

High-Pressure Phase Transformations Under Severe Plastic Deformation By Torsion In Rotational Anvils, Valery I. Levitas

Valery I. Levitas

Numerous experiments have documented that combination of severe plastic deformation and high mean pressure during high-pressure torsion in rotational metallic, ceramic, or diamond anvils produces various important mechanochemical effects. We will focus here on four of these: plastic deformation (a) significantly reduces pressure for initiation and completion of phase transformations (PTs), (b) leads to discovery of hidden metastable phases and compounds, (c) reduces PT pressure hysteresis, and (d) substitutes a reversible PT with irreversible PT. The goal of this review is to summarize our current understanding of the underlying phenomena based on multiscale atomistic and continuum theories and computational modeling ...


Access Mars: Assessing Cave Capabilities Establishing Specific Solutions: Final Report, Abdul Mohsen Al Husseini, Luis Alvarez Sanchez, Konstantinos Antonakopoulos, Jeffrey (Johannes) Apeldoorn, Kenneth Lowell Ashford Jr., Kutay Deniz Atabay, Sara Langston, et al. 2019 Selected Works

Access Mars: Assessing Cave Capabilities Establishing Specific Solutions: Final Report, Abdul Mohsen Al Husseini, Luis Alvarez Sanchez, Konstantinos Antonakopoulos, Jeffrey (Johannes) Apeldoorn, Kenneth Lowell Ashford Jr., Kutay Deniz Atabay, Sara Langston, Et Al.

Sara Langston

The human race has evolved, grown and expanded through the exploration of Earth. After initial steps on the Moon, our next challenge is to explore the solar system. Mars shows potential for both scientific discovery and future human settlement, and so is a prime candidate for the next leap of human exploration. Such a bold endeavor will be a driver for an unprecedented worldwide cooperative effort and the catalyst for a new era of international, intercultural and interdisciplinary human relations. Scientific and technological progress will also accelerate as mankind is ushered into a new era of space exploration.

Currently proposed ...


Optimization Of Takeoffs On Unbalanced Fields Using Takeoff Performance Tool, Nihad E. Daidzic 2019 AAR Aerospace Consulting, LLC

Optimization Of Takeoffs On Unbalanced Fields Using Takeoff Performance Tool, Nihad E. Daidzic

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

Unbalanced field length exists when ASDA and TODA are not equal. Airport authority may add less expensive substitutes to runway full-strength pavement in the form of stopways and/or clearways to basic TORA to increase operational takeoff weights. Here developed Takeoff Performance Tool is a physics-based total-energy model used to simulate FAR/CS 25 regulated airplane takeoffs. Any aircraft, runway, and environmental conditions can be simulated, while complying with the applicable regulations and maximizing performance takeoff weights. The mathematical model was translated into Matlab, Fortran 95/2003/2008, Basic, and MS Excel computer codes. All existing FAR/CS 25 takeoff ...


Long And Short-Range Air Navigation On Spherical Earth, Nihad E. Daidzic 2019 AAR Aerospace Consulting, LLC

Long And Short-Range Air Navigation On Spherical Earth, Nihad E. Daidzic

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

Global range air navigation implies non-stop flight between any two airports on Earth. Such effort would require airplanes with the operational air range of at least 12,500 NM which is about 40-60% longer than anything existing in commercial air transport today. Air transportation economy requires flying shortest distance, which in the case of spherical Earth are Orthodrome arcs. Rhumb-line navigation has little practical use in long-range flights, but has been presented for historical reasons and for comparison. Database of about 50 major international airports from every corner of the world has been designed and used in testing and route ...


Modeling And Computation Of The Maximum Braking Energy Speed For Transport Category Airplanes, Nihad E. Daidzic 2019 AAR Aerospace Consulting, LLC

Modeling And Computation Of The Maximum Braking Energy Speed For Transport Category Airplanes, Nihad E. Daidzic

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

Transport-category or FAR/CS 25 certified airplanes may occasionally become braking energy capacity limited. Such limitation may exist when heavy airplanes are departing airports at high-density altitudes, on relatively long runways, and/or possibly with some tailwind component. A maximum braking energy VMBE speed exists which may limit the maximum allowable takeoff decision/action speed V1. The ever-existing possibility of high-speed rejected takeoff in such conditions may also limit the airplane gross weight for declared available distances. To gain deeper insights and acquire better understanding of the topic, a theoretical model of the maximum braking energy and the related VMBE ...


Improving Airplane Touchdown Control By Utilizing The Adverse Elevator Effect, Nihad E. Daidzic Ph.D., Sc.D. 2019 AAR Aerospace Consulting, LLC

Improving Airplane Touchdown Control By Utilizing The Adverse Elevator Effect, Nihad E. Daidzic Ph.D., Sc.D.

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

The main objective of this original research article is to understand the short-term dynamic behavior of the transport-category airplane during landing flare elevator control application. Increasing the pitch angle to arrest the sink rate, the elevator will have to produce negative lift to rotate the airplane’s nose upward. This has an immediate adverse effect of initially accelerating airplane downward. A mathematical model of landing flare based on the flat-Earth longitudinal dynamics of rigid airplane was developed which is realistic only on very short time-scales as pitch stiffness and damping were neglected. Pilot control scenarios using impulse and step elevator ...


Global Optimized Isothermal And Nonlinear Models Of Earth’S Standard Atmosphere, Nihad E. Daidzic, Ph.D., 2019 AAR Aerospace Consulting, LLC

Global Optimized Isothermal And Nonlinear Models Of Earth’S Standard Atmosphere, Nihad E. Daidzic, Ph.D.,

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

Both, a global isothermal temperature model and a nonlinear quadratic temperature model of the ISA was developed and presented here. Constrained optimization techniques in conjunction with the least-square-root approximations were used to design best-fit isothermal models for ISA pressure and density changes up to 47 geopotential km for NLPAM, and 86 orthometric km for ISOAM respectively. The mass of the dry atmosphere and the relevant fractional-mass scale heights have been computed utilizing the very accurate eight-point Gauss-Legendre numerical quadrature for both ISOAM and NLPAM. Both, the ISOAM and the NLPAM represent viable alternatives to ISA in many practical applications and ...


Estimation Of Performance Airspeeds For High-Bypass Turbofans Equipped Transport-Category Airplanes, Nihad E. Daidzic 2019 AAR Aerospace Consulting, LLC

Estimation Of Performance Airspeeds For High-Bypass Turbofans Equipped Transport-Category Airplanes, Nihad E. Daidzic

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

Conventional Mach-independent subsonic drag polar does not replicate the real airplane drag characteristics exactly and especially not in the drag-divergence region due to shock-induced transonic wave drag. High-bypass turbofan thrust is a complicated function of many parameters that eludes accurate predictions for the entire operating envelope and must be experimentally verified. Fuel laws are also complicated functions of many parameters which make optimization and economic analysis difficult and uncertain in the conceptual design phase. Nevertheless, mathematical models and predictions have its important place in aircraft development, design, and optimization. In this work, airspeed-dependent turbofan thrust and the new fuel-law model ...


Efficient General Computational Method For Estimation Of Standard Atmosphere Parameters, Nihad E. Daidzic Ph.D., Sc.D. 2019 AAR Aerospace Consulting, LLC

Efficient General Computational Method For Estimation Of Standard Atmosphere Parameters, Nihad E. Daidzic Ph.D., Sc.D.

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

Knowledge of standard air temperature, pressure, density, speed of sound, and viscosity as a function of altitude is essential information in aircraft design, performance testing, pressure altimeter calibration, and several other aeronautical engineering and aviation science applications. A new efficient computational method for rapid calculations of standard atmospheric parameters up to 86 orthometric km is presented. Additionally, mass and weight of each standard atmospheric layer were calculated using a numerical integration method. The sum of all fractional masses and weights represents the total mass and weight of Earth’s atmosphere. The results obtained here agree well with measurements and models ...


Achieving Global Range In Future Subsonic And Supersonic Airplanes, Nihad E. Daidzic Ph.D., Sc.D. 2019 AAR Aerospace Consulting, LLC

Achieving Global Range In Future Subsonic And Supersonic Airplanes, Nihad E. Daidzic Ph.D., Sc.D.

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

No commercial airplane in service today is able to fly half great-circle distances over the globe and achieve the non-stop or the global range to any antipodal location on Earth. A subsonic jetliner has the optimum cruising speed at Mach numbers approaching the drag divergence Mach number while still preserving relatively high aerodynamic efficiency. Various fuel-flow laws were used to investigate the cruise performance of subsonic and supersonic aircraft. The effect of wind and aircraft weight and how it affects the optimal cruising airspeed was investigated. Of all different operational cruising techniques, the cruise-climb at high Mach numbers is the ...


Design Of Dc-Link Vscf Ac Electrical Power System For The Embraer 190/195 Aircraft, Eduardo Francis Carvalho Freitas, Nihad E. Daidzic 2019 ETEP – Faculdade de Tecnologia de São José dos Campos, Brazil

Design Of Dc-Link Vscf Ac Electrical Power System For The Embraer 190/195 Aircraft, Eduardo Francis Carvalho Freitas, Nihad E. Daidzic

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

A proposed novel DC-Link VSCF AC-DC-AC electrical power system converter for Embraer 190/195 transport category airplane is presented. The proposed converter could replace the existing conventional system based on the CSCF IDGs. Several contemporary production airplanes already have VSCF as a major or backup source of electrical power. Problems existed with the older VSCF systems in the past; however, the switched power electronics and digital controllers have matured and can be now, in our opinion, safely integrated and replace existing constant-speed hydraulic transmissions powering CSCF AC generators. IGBT power transistors for medium-level power conversion and relatively fast efficient switching ...


Determination Of Rejected Landing Roll Runway Point-Of-No-Return And Go-Around In Transport Category Airplanes, Nihad E. Daidzic, Ph.D., Sc.D. 2019 AAR Aerospace Consulting, LLC

Determination Of Rejected Landing Roll Runway Point-Of-No-Return And Go-Around In Transport Category Airplanes, Nihad E. Daidzic, Ph.D., Sc.D.

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

The decelerate-accelerate-takeoff maneuver in transport category airplanes has been discussed. Mathematical model based on total energy conservation has been used to calculate the rejected landing point-of-no-return on a runway which will still enable the airplane to safely execute go-around and achieve regulatory screen heights and takeoff safety speeds. After this point has been exceeded or below the point-of-no-return speed no go-around should ever be considered. Landing long and fast and/or decelerating on slippery runways may very well result in an overrun which could be prevented if the go-around is attempted before reaching this critical runway point. The point-of-no-return on ...


A Contribution Toward Better Understanding Of Overbanking Tendency In Fixed-Wing Aircraft, Nihad E. Daidzic 2019 AAR Aerospace Consulting, LLC

A Contribution Toward Better Understanding Of Overbanking Tendency In Fixed-Wing Aircraft, Nihad E. Daidzic

Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI

The phenomenon of overbanking tendency for a rigid-body, fixed-wing aircraft is investigated. Overbanking tendency is defined as a spontaneous, unbalanced rolling moment that keeps increasing an airplane’s bank angle in steep turns and must be arrested by opposite aileron action. As stated by the Federal Aviation Administration, the overbanking tendency may lead to a loss of control, especially in instrument meteorological conditions. It was found in this study that the speed differential over wing halves in horizontal turns indeed creates a rolling moment that achieves maximum values for bank angles between 45 and 55 degrees. However, this induced rolling ...


Reimagining Icarus: Ethics, Law And Policy Considerations For Commercial Human Spaceflight, Sara M. Langston 2019 Senmurv Consulting LLC

Reimagining Icarus: Ethics, Law And Policy Considerations For Commercial Human Spaceflight, Sara M. Langston

Sara Langston

Commercial human spaceflight presents an area for engaging novel human activity and objectives, to include space exploration, entertainment, transportation and extraterrestrial resource acquisition. The inherent dangers and lack of scientific and medical certainty involved however raise interrelated questions of ethics, bioethics, law and public policy. This is particularly the case with spaceflight participant (SFP) screening, selection, and commercial human spaceflight activities where regulations are currently silent or lacking. In the absence of established law, ethics can play an important role by informing industry standards, policies and best practices. Understanding the fundamental ethical values at stake in the application of new ...


Thermal And Orbital Analysis Of Darkness Cubesat, Katie Dickey 2019 Olivet Nazarene University

Thermal And Orbital Analysis Of Darkness Cubesat, Katie Dickey

Honors Program Projects

Fermi National Accelerator Laboratory is sending a 3U CubeSat into LEO to search for a 3.5 keV photon corresponding to the decay of a theorized dark matter particle called the sterile neutrino. The CubeSat will encounter environmental variations while in orbit that can be computed through an orbital analysis using System’s Tool Kit. In order to minimize thermal noise readout, improve optical resolution, and increase bandwidth, the sensors must be kept below 170K while taking data. This temperature is difficult to achieve due to radiation from the Sun and the Earth’s albedo radiation. Through the thermal analysis ...


A Technology Survey Of Emergency Recovery And Flight Termination Systems For Uas, Richard Stansbury, Wesley Tanis, Timothy Wilson 2019 Embry-Riddle Aeronautical University

A Technology Survey Of Emergency Recovery And Flight Termination Systems For Uas, Richard Stansbury, Wesley Tanis, Timothy Wilson

Richard Stansbury

For safe flight in the National Airspace System (NAS), either under the current interim rules or under anticipated longer-term regulatory guidelines facilitating unmanned aircraft system (UAS) access to the NAS, the UAS must incorporate technologies and flight procedures to ensure that neither people nor property in the air, on the ground, or on or in the water are endangered by the failure of an onboard component, by inappropriate unmanned aircraft (UA) response to pilot commands, or by inadvertent entry by the UA into prohibited airspace. The aircraft must be equipped with emergency recovery (ER) procedures and technologies that ensure that ...


Visualization And Machine Learning Techniques For Nasa’S Em-1 Big Data Problem, Antonio P. Garza III, Jose Quinonez, Misael Santana, Nibhrat Lohia 2019 Southern Methodist University

Visualization And Machine Learning Techniques For Nasa’S Em-1 Big Data Problem, Antonio P. Garza Iii, Jose Quinonez, Misael Santana, Nibhrat Lohia

SMU Data Science Review

In this paper, we help NASA solve three Exploration Mission-1 (EM-1) challenges: data storage, computation time, and visualization of complex data. NASA is studying one year of trajectory data to determine available launch opportunities (about 90TBs of data). We improve data storage by introducing a cloud-based solution that provides elasticity and server upgrades. This migration will save $120k in infrastructure costs every four years, and potentially avoid schedule slips. Additionally, it increases computational efficiency by 125%. We further enhance computation via machine learning techniques that use the classic orbital elements to predict valid trajectories. Our machine learning model decreases trajectory ...


Autonomous Watercraft Simulation And Programming, Nicholas J. Savino 2019 Lynchburg College

Autonomous Watercraft Simulation And Programming, Nicholas J. Savino

Undergraduate Theses and Capstone Projects

Automation of various modes of transportation is thought to make travel more safe and efficient. Over the past several decades advances to semi-autonomous and autonomous vehicles have led to advanced autopilot systems on planes and boats and an increasing popularity of self-driving cars. We simulated the motion of an autonomous vehicle using computational models. The simulation models the motion of a small-scale watercraft, which can then be built and programmed using an Arduino Microcontroller. We examined different control methods for a simulated rescue craft to reach a target. We also examined the effects of different factors, such as various biases ...


Development Of A One-Equation Turbulence Model Based On K-Ε Closure And Its Extension For Computing Transitional Flows By Including An Intermittency Transport Equation, CHENG PENG 2019 Washington University in St. Louis

Development Of A One-Equation Turbulence Model Based On K-Ε Closure And Its Extension For Computing Transitional Flows By Including An Intermittency Transport Equation, Cheng Peng

Engineering and Applied Science Theses & Dissertations

No abstract provided.


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