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Experimental Aerodynamic Analysis Of A Wing-Flap System With Delta Vortex Generators, Charles Roy Mcconnell

Masters Theses

The principle idea upon which the use of vortex generators (VGs) is based has been to control flow separation. The characteristic of VGs has been used to improve lift and alter the stall characteristics of aircraft and has been a relatively common practice for many years. Due to the seemingly limitless range of VG geometries and arrangements, which are largely dependant upon the desired aerodynamic performance, there has been a broad investigation into VG application.

The purpose of this experimental investigation has been to collect data to be used to establish the effects of various delta shaped vortex generators (delta-VGs) …

Viscosity Measurement Technique By Merging Liquid Drops Aboard The International Space Station, Daniel Aaron Lehman

Masters Theses

The efforts reported in this thesis has been to analyze the data from two "Fluid Merging Viscosity Measurement" experiments in order to validate this as a viable method for measuring the viscosity of fluids with known surface tensions. This method involves simultaneously using a numerical analysis code and experimental data to produce matching curves of contact radius versus time and from that a determination of viscosity. Two experiments that were performed, used different liquids (glycerin and 125 Poise silicon oil) and different size ratios between the two drops ( 1 to 1 and O. 3 3 to 1 respectively). The …

Propeller Development Process: Conflict And Cooperation Between The Department Of Defense And Civil Aviation, Nathan Grant Neblett

Masters Theses

The purpose of this thesis was to compare and contrast the acquisition of the Electronic Propeller Control System through both the Department of Defense and Civil Aviation processes controlled by the Federal Aviation Administration (FAA). The author was a planner and participant in the Department of Defense (DoD) process. Information about the Civil Aviation process was obtained via email and telephone communication with participants, some of whom aided both processes.

Strong similarities existed in system design and prototype manufacture for both processes. A large portion of developmental flight test was similar, if not identical. In particular, both the DoD and …

Bio-Derived Fuels For Hybrid Rocket Motors, Joshua David Scholes

Masters Theses

Two bio-derived fuels have been successfully tested in a laboratory scale hybrid rocket combustion chamber located at the University of Tennessee, Knoxville. Pure lard soaked in an open cell sponge matrix and beeswax were both tested using gaseous oxygen as the oxidizer. Given similar testing conditions, these fuels exhibit higher regression rates than the common hybrid rocket propellant HTPB (hydroxyl-terminated polybutadiene), thus overcoming one of the main shortcomings of hybrid rocket fuels. These fuels also have similar or higher regression rates than paraffin-based fuels recently tested by a Stanford University/NASA Ames team. Measured thrusts ranged from 20-140 Newtons, and calculated …

An Experimental Study Of Axisymmetric Cavity Oscillations In Low Speed Incompressible Flow, Jeremy David Brice Smith

Masters Theses

This study is the latest increment of an ongoing research effort at the University of Tennessee Space Institute with the goal of accomplishing a greater understanding of cavity instabilities and or making use of the instabilities to amplify their effects on the flows. An experimental procedure was designed to examine the unsteady pressure pulses that occur when an incompressible fluid (water) flows through an axisymmetric cavity. The length to depth ratios (L/D) examined ranged from about 0.69 to about 6.2, and the average flow Reynolds numbers ranged from 0 to 1.2 million.

Results show that large amplitude oscillations are generated …

Approaches For Autonomous Vehicles In Civil Airspace: Giving Sight To The Blind, Nicholas Scott Hardman

Masters Theses

The growing prevalence of unmanned aerial vehicles (UAVs) brings great potential for public benefit, but in order to fly in civil airspace UAVs must avoid traffic without the benefit of an onboard human. Developing this capability presents many system integration challenges.

This report examines the integration of automated detect, see, and avoid (DSA) systems on aircraft. For context, the need for UAV operations is reviewed. The report then examines how DSA fits into the entire framework for aviation safety. The research, test results, and conclusions that follow provide the necessary information to decide:

• how to test and evaluate new …

Managing The Remaining Service Life Of The T-34c Aircraft, John Howard Rousseau

Masters Theses

The T-34C Airplane has been the primary trainer aircraft of the United States Navy for more than twenty-five years and is reaching the end of its service life. The Navy has delayed the procurement of the replacement T-6A Texan II aircraft for five years, yet does not expect the future training requirements to diminish. This delay in T-6A procurement along with recent observed increases in primary trainer aircraft usage have resulted in the need for the Navy to pay considerable attention to the remaining service life of the T-34C aircraft.

This thesis will discuss the methodology used to determine future …

The Role Of Simulation In The Test And Evaluation Of A Man In The Loop Weapon System, Keith Matthew Henry

Masters Theses

The Department of Defense has attempted to use recent advances in modeling and simulation to improve the acquisition process for weapons systems. This Simulation Based Acquisition brought advances in the process, but considerable disagreement remains over the universal applicability of this approach. This paper focuses on the challenges of applying modeling and simulation to the Test and Evaluation of a weapon system with significant Pilot-Vehicle interface concerns.

The Standoff Land Attack Missile Expanded Response (SLAM ER) is an aircraft-launched missile with GPS/INS guidance for navigation to the target area and Man In The Loop (MITL) control in the terminal phase. …

The Increased Costs Of Restricting The Procurement Of New Capability In Aircraft Modernisation, Michael Roy Barker

Masters Theses

As an element of the Government of Canada, the Canadian Forces are constrained by many financial and administrative regulations intended to ensure that public funds are expended judiciously. When these regulations restrict the acquisition of an improved capability, they may force program managers to accept a less capable product than could be obtained were only a simple cap on the total program cost imposed.

The CP-140 Aurora Navigation and Flight Instruments Modernisation Project is studied, highlighting specific areas where restrictions upon which capabilities could be improved or added, rather than simply how much money could be spent, resulted in program …

An Investigation Of The Rotor Tip Path Height Of The Mh-60s Helicopter In View Of Forklift Clearance In Support Of The United States Navy Medium Lift Shipboard Logistics Mission, Jonathan Patrick Kline

Masters Theses

The purpose of this paper is to summarize Department of the Navy tests performed to measure rotor tip path height of the MH-60S helicopter and present an analysis of collected data to determine if safe cargo loading operations on the MH-60S can be conducted with a forklift while the rotor is engaged. Testing was conducted to measure the dynamic height of the rotor tip path plane during incremental cyclic displacements, rotor response to external disturbances, and pilot tendencies when centering the cyclic control stick. Additional information was gathered on representative forklifts in use on U.S. Navy ships, and shipboard operating …

Using Helmet Mounted Displays To Designate And Locate Targets In The Urban Environment, Freddie Paul Henderson

Masters Theses

Technologies have developed within the last ten years to allow the Helmet Mounted Display (HMD) to be much more effective as an air-to-ground (A/G) weapons cue. HMD A/G accuracy and performance requirements should be added to the Joint Helmet Mounted Cueing System (JHMCS) specifications, detailed to be as good or better than the FA-18 heads-up-display (HUD). Because of target ranging and line-of-sight (LOS) errors, the JHMCS is only used as an area sensor cue in the urban close air support (CAS) role. Therefore, for use against point targets, improvements to JHMCS are needed. LOS errors have to be reduced from …

Cure-Induced Stress Control In Thermosetting Polymer Composites, Richard W. Burgess

Masters Theses

During the cure of polymer matrix composites, induced stresses develop due to shrinkage of the matrix material. Consequences of this can lead to shifting of the reinforcement, adversely affecting final properties of the material, or the induced stresses can alter the final geometry of the part. With the use of a new closed loop feedback program developed, residual stresses built up during cure were minimized. Experiments were performed using the EPON 828 resin with two types of reinforcement, carbon and glass fiber. The residual stress built up during the optimized cure cycle was compared with that produced during the lPanufacturer …

Joint Unmanned Combat Air System Matching Mission Requirements, Performance Capabilities, And Critical Aviation Systems, Kevin M. Claffy

Masters Theses

The Joint Unmanned Combat Air Systems (J-UCAS) acquisition program is a joint Air Force and Navy effort led by the Defense Advanced Research Projects Agency (DARPA) to demonstrate a networked system of unmanned combat air vehicles (UCAV) to effectively and affordably prosecute 21st century combat missions. The potential of these weapon systems to perform dangerous combat missions at a relatively low-cost and low-risk has garnered significant interest from both Congress and the Department of Defense (DoD) and raised expectations that the J-UCAS will replace some of the DoD’s aging tactical aircraft fleet. This paper will address the requirement for the …

Industry Motivated Advancements Of Current Combustion Instability Model: The Conversion Of Volume Integrals To Surface Form, Sean Robert Fischbach

Masters Theses

This study reports a current development in the widely used combustion stability algorithm employed by propulsion industries as a predictive tool for the design of large combustors. It has been recently demonstrated that, by incorporating unsteady rotational sources and sinks in the acoustic energy assessment, a more precise formulation of the acoustic instability in rocket motors can be achieved. The new algorithm, when applied to the linear stability formulation, leads to ten growth rate terms. In this thesis, these ten stability corrections are converted from volumetric to surface integral form. They are further converted to an acoustic form that is …

Long Range Interdiction: Effects Based Justification Of The B-1b Lancer Aircraft, Stanley Clay Jones

Masters Theses

The purpose of this study was to evaluate the B-1B aircraft for the land-based, long-range, ground attack mission and to use that evaluation to support my belief that the B-1B aircraft provides a better platform than U.S. Naval fighter aircraft for the same, based on the effects that each aircraft delivers.

One flight totaling 6.5 hours was flown by the author in the B-1B aircraft during daylight visual meteorological conditions (VMC) and included low level flight, aerial refueling, low altitude weapons delivery, threat simulation at an Electronic warfare range, and terminal area operations. This flight was used to evaluate the …

The Evaluation Of The Low Probability Of Intercept Altimeter (Lpia) And Its Impact On Ea-6b Operations, Daniel Philip Covelli

Masters Theses

The purpose of this study was to evaluate the performance of the Low Probability of Intercept Altimeter (LPIA) Radar Altimeter (RADALT), which was selected to replace the AN/APN-194 RADALT, as installed in the EA-6B Prowler and conclude how the new system will impact the tactical operation of the EA-6B aircraft if allowed to proceed to and pass the operational phase of testing in its current status.

The LPIA was selected to replace the APN-194 as part of the overall EA-6B aircraft Block III test program in order to comply with the Chief of Naval Operations’ (CNO’s) mandate to install the …

Lessons Learned From The Incorporation And Testing Of The An/Apg-68 Radar On The United States Naval Test Pilot School Airborne Systems Training And Research Support Aircraft (Astars), Denis Gerald Tri

Masters Theses

In August 1994, a Statement of Work (SOW) was issued for the design, installation, and integration of Government Furnished Equipment (GFE) and Commercial Off The Shelf (COTS) technology on a U.S. Naval Test Pilot School (USNTPS) aircraft. The program was known as the Airborne Systems Training and Research Support (ASTARS) Aircraft.

The proposed aircraft would train test pilot students throughout the globe on airborne systems flight test techniques. The concept was initiated from a cancelled A-12 design bed and would be built on a P-3 Orion aircraft. In April 1995, the proposal to build the ASTARS aircraft was accepted, resulting …

A Case For A Tanker Capability For The U. S. Marine Corps’ Heavy Lift Replacement Helicopter, Anthony Cain Archer

Masters Theses

The idea behind this research project was to stimulate interest, dialogue, exploratory investigation, and the application of resources into the concept of an organic, rotary wing based, tanker asset for the U.S Navy’s Expeditionary Strike Group, and its future operations and role in support of Sea Power 21. Material presented was gleaned from numerous aircraft flight manuals, program office documents, contractor literature, and the author’s experiences as a Fleet Marine Force CH-53E pilot. Mission systems are presented using readily available equipment in untested configurations using proven tactics and historical experiences. The results and conclusions make plain the need for …