Operations and Supply Chain Management Commons^™

Monte Carlo Simulation Models To Enhance Air Cargo Network Resilience And Sustainability, Shereen Marie Hashemi

Doctoral Dissertations and Master's Theses

This dissertation focuses on developing and validating an empirical set of simulation models for an air cargo network under large-scale disruption to test recovery strategies that improve resilience. Understanding and quantifying network resilience and recovery strategies is critical for ensuring sustainable operations. These operations become essential during disruptive events as air cargo is used to transport time-sensitive and critical goods. The collective research steps result in a Monte Carlo simulation framework to evaluate air cargo network resilience and identify strategies that enhance performance during disruptions.

The modeled system is a hub-and-spoke network centered on Memphis (MEM) with 23 domestic airports …

Impacts Of Climate Disruption On Mobility Aircraft Performance In The Pacaf Region, Hannah M. Dauterman

Theses and Dissertations

This thesis investigates the projected impacts of climate disruption on the performance and fuel management of the C-17 Globemaster III, a critical mobility aircraft in the Pacific Air Forces (PACAF) region. As rising global temperatures reduce air density, the performance of aircraft is compromised, resulting in increased fuel consumption, as well as the potential for extended runway requirements and diminished cargo capacity. Using climate projection data from Coupled Model Intercomparison Project Phase 6 (CMIP6), this research analyzes future air temperature trends and their implications for C-17 fuel consumption. Results suggest that by 2049, the U.S. Air Force may incur an …

Köppen-Geiger Climate Effects On F-15 Readiness Spares Package Parts, Maximus A. Fan

Theses and Dissertations

Readiness Spares Packages (RSP) are critical to deployed operations. Future demands of the Air Force require squadrons to operate in different climate environments from home stations. RSPs can sustain aircraft maintenance operations for up to 30 days. Currently, failure rates of parts within the RSP are assumed to be constant. This research aims to explore whether there is a difference in F-15 RSP failure rates when Koeppen climate classifications are taken into effect. The Koeppen-Geiger system classifies area climates based on the geography, elevation, and location. The history of operations and diversity of F-15 locations make the aircraft an ideal …

Unleaded Aviation Fuel: Assessing Stakeholder Perceptions And Preparing An Organization For Change, Ryan Guthridge, Nicholas D. Wilson, Brandon Wild

Journal of Aviation Technology and Engineering

Since the Clean Air Act of 1996 banned the use of leaded fuel for automotive applications, leaded aviation gasoline (AVGAS) has become one of the leading sources of lead pollution in the nation due to the volume of AVGAS consumed in general aviation applications (GAMA, 2019). The Federal Aviation Administration has recently recognized this concern with the establishment of the Eliminate Aviation Gasoline Lead Emissions (EAGLE) initiative, which was formally established in February 2022 to foster an important campaign to research and inform the general aviation community on the process for transitioning to unleaded AVGAS. This essay seeks to inform …

Distribution Comparisons Of Eac Cost Growth For Aircraft Work Breakdown Structure Elements, Kyle P. Marquis, Edward D. White, Brandon M. Lucas, Robert D. Fass, Jonathan D. Ritschel, Shawn M. Valentine

Faculty Publications

This article analyzes and investigates the distribution of cost growth of the Estimate at Completion (EAC) for the Work Breakdown Structure (WBS) elements of approximately 60 historical United States Acquisition Category I Research, Development, Test and Evaluation aircraft programs. Using the method of maximum likelihood in conjunction with the Akaike Information Criterion, the authors suggest that both the lognormal and Weibull distributions provide relatively good fit to EAC cost growth, with the lognormal slightly edging out the Weibull. As a summarized finding, the authors present their empirical results for the mean, coefficient of variation (CV), the 15th and 85th percentiles …

Enhancing Reliability Of A 3d Cargo Scanning System, Gabriel F. Bartolomei

Theses and Dissertations

Recent advancements in 3D cargo scanning and machine learning offer solutions to improve cargo processing reliability. This study enhances a 3D cargo scanning system by addressing software crashes, connectivity failures, and image accuracy issues limiting its operational effectiveness. A systematic approach identified the primary causes of system failures. System updates were implemented, followed by 30 pre- and post-update trials to evaluate reliability improvements. Statistical t-tests showed a significant reduction in failures, although processing time slightly increased. Results indicated that targeted hardware and software updates enhanced cargo scanning efficiency and dependability. Future work will focus on refining sensor calibration, optimizing network …

Training-Informed Air Traffic Control Workforce Scheduling, Eli Winett

Theses and Dissertations

The Radar Control Facility (RCF) at Eglin Air Force Base creates monthly workforce schedules. Adherence to regulations must be verified manually and no evaluation criteria exist to compare schedules. A mixed-integer program model for air traffic controllers allocates workers across 19 positions for a user-defined number of weeks of 24-hour operations. Across eight consecutive months, this model produced schedules to nearly eliminate all shifts with critical shortages from the reference schedules. Without civilian overtime work, gains in positional coverage require a 35% increase in overtime work for military workers and 35% reduction in monthly training instances. We recommend users adopt …

The Impact Of Solar Angle And Cloud Shadows On 3d Reconstruction Of Rolling Stock Cargo, Carlina M. Ostrand

Theses and Dissertations

Meeting the relentless demand for more efficient air cargo transportation is paramount. This paper explores an innovative approach, harnessing cutting-edge stereoscopic vision technology to create 3D point clouds of rolling stock cargo, adaptable to varying solar angles and cloud shadow conditions. A virtual cargo image is generated by systematically organizing depth and location points. Accuracy is rigorously tested across six camera positions offering detailed, real-time insights for optimized cargo loading in unpredictable outdoor conditions. The findings reveal the impact of solar positioning, cloud coverage, & camera placement, pushing the boundaries of possibilities for cargo logistics in challenging environments.

Examining The Effect Of Contractor Logistics Support On The Reliability Of Military Aircraft, Rodrigo S. Campos De Moura

Theses and Dissertations

This study utilizes survival analysis for examining the effect of Contractor Logistics Support (CLS) on the reliability of military aircraft before and after implementing CLS. The provider of CLS in this study is the original equipment manufacturer that designed and produced the target aircraft of this study, the Embraer A-29 Super Tucano.

Investigating Supply Parts Delivery Delay From Supply Depot To King Khaled Air Base In Royal Saudi Air Force, Rashed S. Alkhathami

Theses and Dissertations

Aircraft supply parts is an important factor in preparing the aircraft to do its mission. Due to delayed delivery of parts or inefficient delivery process, time may be lost waiting for aircraft supply parts, causing mission delay or failure. By tackling the delivery delay causes we can insure improvement on delivery process. In order to gather data for this thesis two different tools were used, aircraft parts data and an interview. Data was gathered from the F15 maintenance and supply squadrons in the Royal Saudi Air Force. Results of this research showed diverting in the main duty of supply depot …

Supply Chain Resilience: How Autonomous Rovers Empirically Provide Relief To Constrained Flight Line Maintenance Activities, Mary A. Stanton, Jason Anderson, John M. Dickens, Lance Champagne

Faculty Publications

Purpose – The purpose of this research is to explore the utility of autonomous transport across two independent airframe maintenance operations at a single location. Design/methodology/approach – This study leveraged discrete event simulation that encompassed real-world conditions on a United States Air Force flight line. Though the Theory of Constraints (TOC) lens, a high-demand, human-controlled delivery asset is analyzed and the impact of introducing an autonomous rover delivery vehicle is assessed. The authors’ simulations explored varying numbers and networks of rovers as alternative sources of delivery and evaluated these resources’ impact against current flight line operations. Findings – This research …

Transportation Service Level Impact On Aircraft Availability, Vincent Mclean, Adam D. Reiman

Faculty Publications

Purpose — Aircraft fail to meet mission capable rate goals due to a lack of supply of aircraft parts in inventory where the aircraft breaks. This triggers an order at the repair location. To maximize mission capable rate, the time from order to delivery needs to be minimized. The purpose of this research is to examine the case of three airfields for the order to delivery time of mission critical aircraft parts for a specific aircraft type. Design/methodology/approach — This research captured data from three information systems to assess the order fulfillment process. The data were analyzed to determine the …

Qualitative Findings From The Practice Of Outsourcing By The Aviation Technical Services Industry In Northern Europe: Comparison With Literature, Jukka Holkeri

Journal of Aviation Technology and Engineering

The outsourcing of maintenance and other technical services is a trend in both military and civil aviation. This article uses input from real outsourcing cases in Northern Europe to verify previous literature findings and to introduce new viewpoints to fill an identified research gap.

Interviews of deeply involved individuals from six cases were selected and analyzed using the Delphi method. The findings were synthesized using a framework that articulates contexts, observed outcomes, and generative mechanisms.

Many of the key literature findings were verified by this case analysis, but there were also some contradictions and new observations that had not been …

Sortie-Based Aircraft Component Demand Rate To Predict Requirements, Thomas R. O'Neal, John M. Dickens, Lance Champaign, Aaron V. Glassburner, Jason R. Anderson, Timothy W. Breitbach

Faculty Publications

Purpose — Forecasting techniques improve supply chain resilience by ensuring that the correct parts are available when required. In addition, accurate forecasts conserve precious resources and money by avoiding new start contracts to produce unforeseen part requests, reducing labor intensive cannibalization actions and ensuring consistent transportation modality streams where changes incur cost. This study explores the effectiveness of the United States Air Force’s current flying hour-based demand forecast by comparing it with a sortie-based demand forecast to predict future spare part needs. Design/methodology/approach — This study employs a correlation analysis to show that demand for reparable parts on certain aircraft …

Analyzing The Effect Of Delta Airlines' Fleet Upgrade On Operations At Atlanta-Hartsfield Jackson International Airport, Carlos Alberto Castro, Shlok Misra

Publications

Commercial aviation has seen a growth in terms of passengers traveled and flights operated in the past decade (BTS, 2020). To cope up with this growth, airlines adopt various strategies such as network expansion and fleet upgrades. Airlines adopt fleet upgrade strategies to modernize their fleet, reduce costs, expand network coverage, and improve customer loyalty and experience. Research suggests that change in wake turbulence categorization and aircraft performance can directly impact the movements and delays at an airport. For this study, Delta Airline's fleet upgrade program and its effect on operating parameters at Atlanta-Hartsfield Jackson International Airport were analyzed. The …

The Obstacles To The Modernization Of Common Support Equipment, J. Erik Ritschard

Theses and Dissertations

The current fleet of Common Support Equipment (CSE) is faced with a $2B funding disconnect that threatens 9 of the 12 USAF Core Functions. This research identifies the barriers to efforts to modernize CSE across the sustainment, acquisition, and maintenance communities. Using a qualitative, grounded theory methodology, the responses are explored of interviewed Support Equipment managers responsible for the sustainment and modernization of CSE. Significant barriers to current modernization efforts were exposed, resulting in expensive, duplicative, and unreliable equipment; concluding that the AF must change the way CSE is administrated, funded, and culturally understood to prevent future mission degradation.

Resilient Maintenance Infrastructure: Dynamic Repair Network Designs To Effectively Manage Supply Chain Disruptions, David W. Wallace Iii

Theses and Dissertations

Supply chains are facing numerous changes contributing to their increase in complexity and vulnerability to disruptions. Subsequently, decision-makers lack a transparent, generalizable tool to quantify supply chain resilience and assess additional resilience investments. This research facilitates a more profound understanding of the intricacies and interrelation of supply chain nodes and constructs. It integrates the Area under the Curve (AUC) metric to quantify performance or any organizational measure of competitive advantage amid a disruption. Due to its structural resemblance to various organizational platforms, the subset United States Air Force (USAF) F-16 engine repair and supply network is modeled employing discrete-event simulation. …

Managing Quality In Aviation Projects, James W. Marion, Tracey M. Richardson, Vittal Anantatmula

Publications

From aircraft manufacturing, product customization, aircraft maintenance, and aircraft launch and recovery, project management is threaded through all aspects of aviation. Given the supreme importance of quality to every aircraft manufacturer, airline, and passenger, it would be expected that quality management, within the context of project management, would be a construct that is clearly defined. The aim of this mixed-methods research seeks to understand how quality is managed and assured in aviation projects, whether or not the current quality management framework is applicable to the aviation industry, and how quality should ultimately be managed in aviation projects. The results of …

Quantifying The Effects Of Aircraft Engine Upgrades On Operating And Support Costs, Bradford A. Myers, Edward D. White, Jonathan D. Ritschel, R. David Fass

Faculty Publications

For fixed wing aircraft within the U.S. Air Force, Operating and Support (O&S) costs encompass a large portion of total life cycle costs. O&S costs include fuel, maintenance, and engine upgrades. To the authors’ knowledge, no study to date has attempted to empirically quantify the realized effects of new aircraft engines on sustainment costs. Utilizing the Air Force Total Ownership Cost database, they focused on new engines appearing on the C-5s, C-130s, and C-135s. Although narrow in scope, results suggest newer engines have lower fuel costs. Maintenance costs for newer engines were not consistently higher or lower than the engines …

Investigation Of An Avionics Part Deficiencies In Royal Saudi Air Force Fleets, Nasser S. Alanazi

Theses and Dissertations

The Royal Saudi Air Force (RSAF) is experiencing a shortage in certain avionics parts due to a lack of reliability. This issue is causing a supply chain disturbance in the F1-15 fleet and the Hawk fleet. One of the factors behind this problem is the environmental effects in Saudi Arabia .The study will investigate and analyze the methods for the Improvement Cycle Processes and the Quality Management within the RSAF repair cycle. Finding show that, the discrepancies are rising during summer and fall time due to the environment change, Other finding were addressed in the study.

Sortie-Based Aircraft Component Demand Rate To Predict Requirements, Thomas R. O'Neal

Theses and Dissertations

Weapon System Sustainment (WSS) costs are growing at an increasing rate despite the vast efforts to reduce them. Researchers have attributed much of the cost increase to inaccurate demand forecasts for weapon system spare parts. In 2011, the forecast to sustain all United States Air Force (USAF) aircraft was 19% accurate and WSS costs per year have continuously increased. The purpose of this study is to explore a parsimonious change to aircraft component forecasting to reduce costly forecast error. This study substitutes flying hours with sorties for the purpose of demand forecasting. Many F-16 and B-52 spare parts are evaluated …

Resilient Aircraft Sustainment: Quantifying Resilience Through Asset And Capacity Allocation, Zachary B. Shannon

Theses and Dissertations

Decision makers lack a clear, generalizable method to quantify how additional investment in inventory and capacity equates to additional levels of resilience. This research facilitates a deeper understanding of the intricacies and complex interconnectedness of organizational supply chains by monetarily quantifying changes in network resilience. The developed Area under the Curve metric (AUC) is used to quantify the level of demand that each asset allocation can meet during a disruptive event. Due to its applicability across multiple domains, the USAF F-16 repair network in the Pacific theater (PACAF) is modeled utilizing discrete event simulation and used as the illustrating example. …

Inherent Jeopardy Of Performance Based Contracting Metrics: A Simulation Experiment, Daniel Cherobini

Theses and Dissertations

There is a growing trend across the world to adopt Performance Based Contracting strategies to support logistics systems. Using these policies, contract payments are strongly related to the performance achieved compared to prespecified metrics. However, managers are not always confident on what are the most suitable performance goals to use in these agreements. As a consequence, contractors struggle to deliver the desired performance results, while aircraft fleets experience an increase in support costs. And when the results are inadequate, leaders are tempted to impose even more performance targets to contractors, willing to exercise more control over the support organization. In …

Undergraduate Pilot Training Attrition: An Analysis Of Individual And Class Composition Component Factors, Christina M. Akers

Theses and Dissertations

The Air Force is working hard to reduce the shortage of nearly 2,000 pilots that threatens the Air Force’s core mission. Officials have focused on increasing retention and training throughput. Despite this, the first Pilot Training Next class graduated in August of 2018 with 13 of the initial 20 students (65.5% graduation rate). The purpose of this research is to explore attrition reduction by understanding how class composition of individual abilities and personalities affects the class graduation rate. Using AFOQT scores, SDI+ scores, PCSM scores, flight hours, and college GPAs, correlations were studied and a simple linear regression was run …

Efficiency Analysis Of A Congested Brazilian Airport Applying Slots Optimization Control: Congonhas Airport Case, Mariana Franco B. Mendes, Rafael Roco De Araujo, Ana Paula Beck Da Silva Etges, Massoud Bazargan

International Journal of Aviation, Aeronautics, and Aerospace

The current slot allocation mechanism in Brazil, based on the International Air Transport Association (IATA) rules, and its supplementary local regulation The National Civil Aviation Agency (ANAC), displays a few issues and limitations (e.g. slot misuse, allocation inefficiencies). Such issues are particularly present in the case of busy airports that works near their maximum capacity for major parts of the day. This inefficiency problem is generated because of the complexity of slot allocation added to the limited decision support available for the Brazilian system. This study focuses on the implementation of an optimal slot model, based on IATA regulations with …

Order Fulfillment Errors And Military Aircraft Readiness, Michael Weber, Daniel Steeneck, William Cunningham

Faculty Publications

This paper aims to measure the effect of supply discrepancy reports (SDRs) on military aircraft readiness metrics, including aircraft availability, not mission capable supply (NMCS) hours, cannibalizations and mission-impaired capability awaiting parts (MICAP) hours.

Monthly SDR, NMCS, aircraft cannibalizations and MICAP data from 2009 to 2018 are analyzed using linear regression and independent samples t-tests to examine whether discrepant shipments negatively impact aircraft readiness.

Taking Off In Africa: Critical Elements Of Aircraft Engine Manufacturer Engagement That Can Affect Airline Safety Performance, Nathan Michael Woods

Antioch University Dissertations & Theses

Original Equipment Manufacturer (OEM) is a term used in many industries to describe a company that produces parts and equipment that may be marketed by another manufacturer. In the aviation industry, the aircraft engine OEM refers to the company the manufactures engines powering the aircraft. The OEM manufactures the engine, defines the required maintenance to operate the engines, and recommends product modifications. Product modifications are recommended to improve product safety, durability, reliability, and cost of ownership and are formally communicated through issuance of service bulletins. Properly performing the required maintenance and adopting service bulletins is an important element of maintaining …

A Study On Spare Aircraft In Brazilian Airlines, Clarissa Pinheiro Pereira, Eduardo Sakashita, Eliudes Del Grande, Guilherme Bevilacqua

Graduate Student Works

All around the globe, the airlines struggle to sustain profitability. They are deeply affected by the region’s economy. It goes from the fuel price and exchange rate to the level of employment and average salary. That makes it imperative to control the cost, and also to balance very well the cost and level of service. Aircraft utilization is one KPI that measures productivity. Once the airline has a high aircraft utilization, it means that the resource has been productive, hence more cost-efficient.

On the other hand, flight cancelations and delays result in costs and passengers’ dissatisfaction. In Brazil, there is …

Evaluation Of Rsaf Airworthiness And Applicability, Majed M. Altowairqi

Theses and Dissertations

This research focuses on evaluation of Royal Saudi Air Force (RSAF) airworthiness processes and their applicability. The current RSAF airworthiness process is in accordance with internationally recognized best practice in the area of military aviation, this is achieved by benchmarking against European Aviation Safety Agency (EASA) and International Organization for Standardization (ISO) standards. Airworthiness policy for the RSAF is developed on the basis that it will be as civil as possible and as military as necessary. For the purpose of this research, the current RSAF airworthiness process will be benchmarked against the United States Air Force (USAF) airworthiness process. That …

Managing Supply Discrepancies: The Effect Of Performance Measurement And Feedback On Order Fulfillment Quality, Michael J. Weber

Theses and Dissertations

Extensive research on the impact of shipping and packaging errors in the private sector finds numerous negative outcomes, including reduced customer satisfaction, reduced customer loyalty, and lower profitability. However, little research has been done examining the impact of order fulfillment errors on military operations. The purpose of this research is to quantify the impact of supply discrepancy reports (SDRs) on military aircraft readiness metrics, including cannibalizations, not mission capable supply (NMCS) hours, aircraft availability and MICAP hours. Results show SDRs significantly impact aircraft readiness metrics in seven of the fifteen analyses conducted. Additionally, a quasi-experimental study is implemented at DLA …