Aerospace Engineering Commons^™

Evolution Of A Monomer Concentration Field In A Micro-Fluidic Channel, Michael Francis Kirsch

Masters Theses

The purpose of this research is to determine how long a micro-channel could be in the production of Non-Linear Optical Thin Film Wave-Guides. In determining this length, it is necessary to compute the monomer diffusion process between two solutions of monomers in a micro channel flow. Two models of this flow were created, the first with no flow in a one dimensional channel making diffusion a function of time and position and the second of flow in a two dimensional channel with an imposed velocity profile. Using these models it was determined that the micro channel could be the longest …

F/A-18e/F Catapult Minimum End Airspeed Testing, Michael M. Wallace

Masters Theses

The F/A-18E/F Super Hornet is the result of major upgrades to previous series of F/A-18 Hornet aircraft (F/A-18A/B/C/D). These upgrades resulted in an airplane requiring a complete Engineering and Manufacturing Development (EMD) phase. Catapult minimum end airspeed tests took place near the end of the three and a half year EMD program to provide data for the Aircraft Launch Bulletin for Operational Evaluation and fleet operations. The tests had occurred on average only every six years for any type of aircraft and 10-15 years for the same model of aircraft in the last 30 years.

The objective of this thesis …

Developmental Flight Test Of A Powered Approach Stability Augmentation System On The U.S. Navy's E- 2c Hawkeye 2000 Aircraft, Robert K. Williams

Masters Theses

The E-2C aircraft is a Navy carrier based high-wing, twin engine turboprop powered aircraft used for the Airborne Early Warning (AEW) mission. In the power approach configuration, the aircraft displays strong adverse yaw, weak directional stability, and excessive rudder control power. These antagonistic characteristics, when coupled together, result in an extremely high workload for the pilot during both carrier and field landings. Although the aircraft has a yaw axis stability augmentation system, it is currently only applicable to cruise conditions. Engaging the stability augmentation in the power approach configuration results in a 1 Hz directional oscillation due to the system’s …

Transient Jet Interaction Force And Moment Reconstruction In Dynamic Wind-Tunnel Testing, Mark Edward Smith

Doctoral Dissertations

In recent years there has been an increased interest in understanding the effect of missile divert jets upon the pressure distribution on the surface of a missile. Missile divert jets are jets located near the missile center of mass and thrusting along a lateral axis of a missile. The firing of a divert jet perturbs the pressure dis- tribution and thus alters the aerodynamic force acting on the missile. This is the aerodynamic jet interaction e®ect. It is essential to characterize and understand this effect when designing robust missile autopilots.

Testing techniques for determining the transient jet interaction effect must …

Design And Integration Of A Display For A Low Cost Laser Altimeter For General Aviation Applications, Scott Edward Hutcheson

Masters Theses

This project began when Opti-Logic, a local manufacturer of laser rangefinders for military and sporting applications, expressed a desire to design an altimeter for General Aviation application to measure absolute altitude based on the laser range finder as a sensor. The sensor they chose was the RS400, which was originally designed for security applications. The purpose of this thesis was to aid Opti-Logic by designing and flight-testing an intuitive display for the laser altimeter. A Systems Engineering approach was used throughout the design process. A basic assumption in the design of the system is that a suitable laser sensor was …

A Study Of The Chemistry Between Fast Atomic Oxygen And Silver-Coated Qcm Crystals, Juan Carlos Valer

Masters Theses

Atomic Oxygen (AO) is the main constituent of Low Earth Orbit (LEO), and it is responsible for chemical reactions on spacecraft materials that may degrade the performance or terminate the usefulness of them, and eventually accelerate the end of the life of the vehicle. This situation has make it clear the need to simulate the AO flux of LEO in a ground laboratory, to better understand the mentioned interactions.

MSRI and a UTSI team lead by Dr. Frank Collins have heavily modified an atomic oxygen generator originally fabricated by Dr. Gar Hoflund that promises to at least duplicate the AO …

The Correlation Of Pedal Position To Tail Rotor Power Requirement On The Oh-58a+, Kan-Wai Tong

Masters Theses

Every mechanical component has a finite failure life. Excessive usage of a component may cause damage. Therefore, life determination is essential to safe operation. Replacement of mechanical components prior to the end of useful life results in higher costs of maintenance. Monitoring rotating components is not always reliable or cost effective. This thesis attempts to solve this problem for a helicopter tail rotor. The development of an algorithm to calculate the loads on a component using stationary measurements can eliminate the need for rotating measurement equipment.

The purpose is to predict the tail rotor power requirement of a helicopter throughout …

Implementation Of The Digital Communication System In The F/A-18 Aircraft, Gregory D. Bigalk

Masters Theses

The F/A-18 Hornet is a Navy/Marine Corps carrier-based strike/fighter built by the Boeing Company. The Hornet is a dual role aircraft designed to have all weather intercept and ground attack capabilities. The purpose of this study was to examine the Variable Message Format (VMF) communications capability, integration compatibility and technical suitability of the RT-1824(C) ARC-210 radio as integrated into the F/A-18 aircraft. Normally, this aircraft would utilize two ARC-210 voice capable only RT-1556 radio sets designated Comm 1 and Comm 2. Comm 1 is switchable between an upper AS-4129/ARC antenna and lower AS-3557/A antenna. Comm 2 utilizes a separate lower …

Evaluation Of A Two-Way Datalink For Airborne Surveillance Of And Communication With A Remotely Operated Aircraft Operating In The National Airspace System, Timothy R. Clark

Masters Theses

The purpose of this study is to examine the use of a two-way digital datalink to implement the airborne surveillance and communication functions with a Remotely Operated Aircraft in the National Airspace System. These Air Traffic Control functions are currently implemented using primary and secondary radar systems for airborne surveillance, and radio transmissions for voice communications.

The present Air Traffic Control system was examined, as well as existing datalink technologies and surveillance and communication equipment. Remotely Operated Aircraft are currently employed almost exclusively by the military, and operational experience in the National Airspace System is very limited. Several key military …

Integration Of The Control Display Navigation Unit (Cdnu) Into The Ea-6b Block 89a Aircraft And Its Impact On Navigation Operations, Robert Donald Croxson

Masters Theses

This thesis was to evaluate the attributes of the recent modification and installation of the Control Display Navigation Unit (CDNU) into the EA-6B aircraft. The author conducted multiple ground and flight test events during a three year evaluation of the EA-6B Block 89A aircraft.

The Block 89A modification included an embedded Global Positioning System (GPS)/ Inertial Navigation System (INS) (EGI), enhanced functionality with the recent GPS system modification, and the ability to control the navigation, weapon, and communication on one control panel. This modification was an attempt to replace a failing attitude system and also allow for additional capability. The …

Sidestick Controllers During High Gain Tasks, Brian J. Goszkowicz

Masters Theses

This research attempts to demonstrate the feasibility of a sidestick controller in a high gain environment. The research is assembled from several historical precedents and various projects.

New technologies have re-ignited interest in the use of sidestick controllers for commercial and military aircraft. There are many advantages and disadvantages utilizing a sidestick in fighter aircraft. Many pilots prefer the feel of a centerstick controller and the designer only needs to develop a few sets of command gradients or gearings to produce adequate handling qualities. However, centersticks require more cockpit room due to their larger size and range of motion. Consequently, …

Computational Investigation Of The Discharge Coefficient Of Bellmouth Flow Meters In Engine Test Facilities, Charles Lynn Sebourn

Doctoral Dissertations

In this thesis computation of the discharge coefficient of bellmouth flow meters installed in engine test facilities is presented. The discharge coefficient is a critical parameter for accurately calculating flow rate in any flow meter which operates by means of creating a pressure differential. Engine airflow is a critical performance parameter and therefore, it is necessary for engine test facilities to accurately measure airflow.

In this report the author investigates the use of computational fluid dynamics using finite difference methods to calculate the flow in bellmouth flow meters and hence the discharge coefficient at any measurement desired.

Experimental boundary layer …

An Investigation Of The Effects Of Relative Winds Over The Deck On The Mh-60s Helicopter During Shipboard Launch And Recovery Operations, Dominick J. Strada

Masters Theses

Vertical replenishment (VERTREP) of underway fleet naval vessels by helicopter is the primary mission of the MH-60S helicopter and is absolutely critical to sustaining fleet combat readiness at sea. The effectiveness of the MH-60S helicopter in conducting this crucial mission is directly dependent upon its ability to launch from and recover to the delivery ship under a wide range of wind-over-deck (WOD) conditions.

This thesis is an investigation of the effects of relative winds over the deck on the MH-60S helicopter documented during shipboard launch and recovery operations conducted during the initial MH-60S shipboard testing and launch and recovery wind …

Neural Network Model Of Unsteady, Nonlinear Aerodynamics, Amy Pearsall Henderson

Masters Theses

Many flight control systems are developed from aerodynamic measurements obtained from static wind tunnel testing. These control systems frequently inadequately handle unsteady, nonlinear flight conditions. Dynamic roll angle measurements made in a wind tunnel have been obtained. This aerodynamic data presents a nonlinear, unsteady dynamical system. The roll angle trajectories have been successfully approximated with multilayer feedforward backpropagation neural networks.