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- Transportation service level impact on aircraft availability
Authors:
Vincent McLean
,
Adam D. Reiman
Abstract: 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. This research captured data from three information systems to assess the order fulfillment process. The data were analyzed to determine the performance in fiscal year 2020. Using the model of that performance, the cost of reducing transportation times using publicly available commercial cost estimates was assessed against the impact on aircraft availability. The results indicate that paying the costs for expedited shipping would have increased aircraft availability by 1.09 times the average annual aircraft flying hours for the three cases. The cost for the equivalent of an additional aircraft for the year was a third of the annual straight-line depreciation for that aircraft type. This research assumed that the transportation time service levels publicly posted could be achieved. The weight of each mission critical part was not available, so the weight was selected from a probability distribution of mission critical part weights that was retrieved from prior research. This research provides options to enhance aircraft availability and identifies the associated costs. Adjusting the contract with transportation providers to reduce the transportation times of mission critical parts could have a large impact on aircraft availability at relatively little cost. This research could enhance aircraft readiness in service of the common defense. This research provides an effective methodology for enhancing military readiness through contract adjustments with commercial partners. The value of this research is that it will serve to adjust the value proposition of mission critical parts inside the United States Transportation Command’s Next Generation Delivery Service contract.
Citation:
Journal of Defense Analytics and Logistics
PubDate:
2022-04-22
DOI: 10.1108/JDAL-10-2021-0010
Issue No: Vol.
ahead-of-print
, No.
ahead-of-print
(2022)
- Pilot development: an empirical mixed-method analysis
Authors:
Jonathan Slottje
,
Jason Anderson
,
John M. Dickens
,
Adam D. Reiman
Abstract: Pilot upgrade training is critical to aircraft and passenger safety. This study aims to identify variances in the US Air Force C-130J pilot upgrade training based on geographic location and provide a model to enhance policy that will impact future pilot training efforts that lower cost and increase operator quality and proficiency. This research employed a mixed-method approach. First, the authors collected data and analyzed 90 C-130J pilots' aviation records and then contextualized this analysis with interviews of experts. Finally, the authors present a modified version of Six Sigma's define–measure–analyze–improve–control (DMAIC) that identifies and reduces the variances in C-130J pilot training, translating into higher quality outcomes. The results indicate significant statistical variances across geographically separated C-130J pilot training organizations. This leads some organizations to have higher proficiency levels in specific tasks and others with comparative deficiencies. Additionally, the data analysis in this study enabled a recommended number of flight hours in several distinct categories that should be obtained before upgrading a pilot to aircraft commander to enhance standards. This research was limited to C-130J pilot upgrades, but these results can be implemented within any field that utilizes hours as a measure of experience. Implications from this research can be employed to scope policy that will influence pilot training requirements across all airframes in civilian and military aviation. This research proposes a process improvement methodology that could be immediately implemented within the C-130J community and, more importantly, in any upgrade training where humans advance into higher echelons of a profession.
Citation:
Journal of Defense Analytics and Logistics
PubDate:
2022-04-19
DOI: 10.1108/JDAL-10-2021-0008
Issue No: Vol.
ahead-of-print
, No.
ahead-of-print
(2022)
- Analysis of vertical lift capabilities of US Navy (USN) in Humanitarian
Assistance and Disaster Relief (HADR)
Authors:
Aruna Apte
,
Scott Chirgwin
,
Ken Doerr
,
Davis Katakura
Abstract: Vertical lift (VL) assets are vital and expensive resources in humanitarian missions. What and where supplies are needed evolves in short time following a disaster. The purpose of this paper is to offer analysis to understand the range of capabilities of these assets. The authors use scenario analysis to investigate the tradeoff between two key capabilities of VL, agility and speed. The authors do this by generating loads and distances randomly, based on historical data. In post hoc analysis, based on different factors, the authors investigate the impact of configuration of Expeditionary Strike Force (ESG) on providing disaster relief. The authors find the most effective deployment of VL in a HADR mission is in supplying essentials to victims in a focused region. Delivering sustainment requirements leads to substantial shortfall for survival needs. If the configuration of the ESGs were changed for HADR, it would better-meet the demand. Cargo capacity is modeled assuming every aircraft type was equal, in terms of mean and variance of cargo-capacity utilization. Detailed information on cargo-bay configurations was beyond the scope of our model and data. However, this means the benefit of standardizing cargo load-outs and the variability associated with randomized load-outs may be understated in the results. The analysis presents decision-makers with projections of VL asset performance in the early stages of disaster relief, to assist in planning and contingency planning. This research deals exclusively with the most critical but expensive capabilities for HADR: VL. The in-depth analysis illustrates the limitations and benefits of this capability.
Citation:
Journal of Defense Analytics and Logistics
PubDate:
2022-03-14
DOI: 10.1108/JDAL-10-2021-0012
Issue No: Vol.
ahead-of-print
, No.
ahead-of-print
(2022)
- Developing a resilient, robust and efficient supply network in Africa
Authors:
Jade F. Preston
,
Bruce A. Cox
,
Paul P. Rebeiz
,
Timothy W. Breitbach
Abstract: Supply chains need to balance competing objectives; in addition to efficiency, supply chains need to be resilient to adversarial and environmental interference and robust to uncertainties in long-term demand. Significant research has been conducted designing efficient supply chains and recent research has focused on resilient supply chain design. However, the integration of resilient and robust supply chain design is less well studied. The purpose of the paper is to include resilience and robustness into supply chain design. The paper develops a method to include resilience and robustness into supply chain design. Using the region of West Africa, which is plagued with persisting logistical issues, the authors develop a regional risk assessment framework and then apply categorical risk to the countries of West Africa using publicly available data. A scenario reduction technique is used to focus on the highest risk scenarios for the model to be tractable. Next, the authors develop a mathematical model leveraging this framework to design a resilient supply network that minimizes cost while ensuring the network functions following a disruption. Finally, the authors examine the network's robustness to demand uncertainty via several plausible emergency scenarios. The authors provide optimal sets of transshipment hubs with varying counts from 5 through 15 hubs. The authors determine there is no feasible solution that uses only five transshipment hubs. The authors' findings reinforce those seven transshipment hubs – the solution currently employed in West Africa – is the cheapest architecture to achieve resilience and robustness. Additionally, for each set of feasibility transshipment hubs, the authors provide connections between hubs and demand spokes. While, at the time of this research, three other manuscripts incorporated both resilience and robustness of the authors' research unique solved the problem as a network flow instead of as a set covering problem. Additionally, the authors establish a novel risk framework to guide the required amount of redundancy, and finally the out research proposes a scenario reduction heuristic to allow tractable exploration of 512 possible demand scenarios.
Citation:
Journal of Defense Analytics and Logistics
PubDate:
2021-12-10
DOI: 10.1108/JDAL-09-2021-0006
Issue No: Vol.
5
, No.
2
(2021)
- GAMES, game theory and artificial intelligence
Authors:
John T. Hanley
Abstract: The purpose of this paper is to illustrate how game theoretic solution concepts inform what classes of problems will be amenable to artificial intelligence and machine learning (AI/ML), and how to evolve the interaction between human and artificial intelligence. The approach addresses the development of operational gaming to support planning and decision making. It then provides a succinct summary of game theory for those designing and using games, with an emphasis on information conditions and solution concepts. It addresses how experimentation demonstrates where human decisions differ from game theoretic solution concepts and how games have been used to develop AI/ML. It concludes by suggesting what classes of problems will be amenable to AI/ML, and which will not. It goes on to propose a method for evolving human/artificial intelligence. Game theoretic solution concepts inform classes of problems where AI/ML 'solutions' will be suspect. The complexity of the subject requires a campaign of learning. Though games have been essential to the development of AI/ML, practitioners have yet to employ game theory to understand its limitations.
Citation:
Journal of Defense Analytics and Logistics
PubDate:
2021-12-07
DOI: 10.1108/JDAL-10-2021-0011
Issue No: Vol.
5
, No.
2
(2021)
- Sortie-based aircraft component demand rate to predict requirements
Authors:
Thomas R. O'Neal
,
John M. Dickens
,
Lance E. Champagne
,
Aaron V. Glassburner
,
Jason R. Anderson
,
Timothy W. Breitbach
Abstract: 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. This study employs a correlation analysis to show that demand for reparable parts on certain aircraft has a stronger correlation to the number of sorties flown than the number of flying hours. The effect of using the number of sorties flown instead of flying hours is analyzed by employing sorties in the United States Air Force (USAF)’s current reparable parts forecasting model. A comparative analysis on D200 forecasting error is conducted across F-16 and B-52 fleets. This study finds that the USAF could improve its reparable parts forecast, and subsequently part availability, by employing a sortie-based demand rate for particular aircraft such as the F-16. Additionally, our findings indicate that forecasts for reparable parts on aircraft with low sortie count flying profiles, such as the B-52 fleet, perform better modeling demand as a function of flying hours. Thus, evidence is provided that the Air Force should employ multiple forecasting techniques across its possessed, organically supported aircraft fleets. The improvement of the forecast and subsequent decrease in forecast error will be presented in the Results and Discussion section. This study is limited by the data-collection environment, which is only reported on an annual basis and is limited to 14 years of historical data. Furthermore, some observations were not included because significant data entry errors resulted in unusable observations. There are few studies addressing the time measure of USAF reparable component failures. To the best of the authors’ knowledge, there are no studies that analyze spare component demand as a function of sortie numbers and compare the results of forecasts made on a sortie-based demand signal to the current flying hour-based approach to spare parts forecasting. The sortie-based forecast is a novel methodology and is shown to outperform the current flying hour-based method for some aircraft fleets.
Citation:
Journal of Defense Analytics and Logistics
PubDate:
2021-12-06
DOI: 10.1108/JDAL-10-2021-0009
Issue No: Vol.
5
, No.
2
(2021)
- An analytical and probabilistic model with concordance for detecting
mine-like objects with mirror symmetry
Authors:
Phuc Bao Uyen Nguyen
Abstract: The purpose is to develop search and detection strategies that maximize the probability of detection of mine-like objects. The author have developed a methodology that incorporates variational calculus, number theory and algebra to derive a globally optimal strategy that maximizes the expected probability of detection. The author found a set of look angles that globally maximize the probability of detection for a general class of mirror symmetric targets. The optimal strategies only maximize the probability of detection and not the probability of identification. In the context of a search and detection operation, there is only a limited time to find the target before life is lost; hence, improving the chance of detection will in real terms be translated into the difference between success or failure, life or death. This rich field of study can be applied to mine countermeasure operations to make sure that the areas of operations are free of mines so that naval operations can be conducted safely. There are two novel elements in this paper. First, the author determine the set of globally optimal look angles that maximize the probability of detection. Second, the author introduce the phenomenon of concordance between sensor images.
Citation:
Journal of Defense Analytics and Logistics
PubDate:
2021-11-23
DOI: 10.1108/JDAL-02-2021-0002
Issue No: Vol.
5
, No.
2
(2021)
- Improving the port selection process during military deployments
Authors:
Dave C. Longhorn
,
Joshua R. Muckensturm
,
Shelby V. Baybordi
Abstract: This paper recommends new criteria for selecting seaports of embarkation during military deployments. Most importantly, this research compares the current port selection criterion, which is to select the seaport with the shortest inland transport time from the deploying installation, to the proposed port selection criteria, which are to select the seaport based on the shortest combined inland and oceanic transit time to the destination theater. The authors construct an original integer program to select seaports that minimize the expected delivery timeline for a set of notional, but realistic, deployment requirements. The integer program is solved considering the current as well as the proposed port selection criteria. The solutions are then compared using paired-samples t-tests to assess the statistical significance of the port selection criteria. This work suggests that the current port selection criterion results in a 10–13% slower delivery of deploying forces as compared to the proposed port selection criteria. This work assumes deterministic inland transit times, oceanic transit times, and seaport processing rates. Operational fluctuations in transit times and processing rates are not expected to change the findings from this research. This research provides evidence that the current port selection criterion for selecting seaports for military units deploying from the Continental United States is suboptimal. More importantly, logistics planners could use these recommended port selection criteria to reduce the expected delivery timelines during military deployments. Several military doctrinal references suggest that planners select seaports based on habitual installation-to-port pairings, especially for early deployers. This work recommends a change to the military's current port selection process based on empirical analyses that show improvements to deployment timelines.
Citation:
Journal of Defense Analytics and Logistics
PubDate:
2021-10-26
DOI: 10.1108/JDAL-04-2021-0003
Issue No: Vol.
5
, No.
2
(2021)
- Performance tradeoffs for spare parts supply chains with additive
manufacturing capability servicing intermittent demand
Authors:
Kyle C. McDermott
,
Ryan D. Winz
,
Thom J. Hodgson
,
Michael G. Kay
,
Russell E. King
,
Brandon M. McConnell
Abstract: The study aims to investigate the impact of additive manufacturing (AM) on the performance of a spare parts supply chain with a particular focus on underlying spare part demand patterns. This work evaluates various AM-enabled supply chain configurations through Monte Carlo simulation. Historical demand simulation and intermittent demand forecasting are used in conjunction with a mixed integer linear program to determine optimal network nodal inventory policies. By varying demand characteristics and AM capacity this work assesses how to best employ AM capability within the network. This research assesses the preferred AM-enabled supply chain configuration for varying levels of intermittent demand patterns and AM production capacity. The research shows that variation in demand patterns alone directly affects the preferred network configuration. The relationship between the demand volume and relative AM production capacity affects the regions of superior network configuration performance. This research makes several simplifying assumptions regarding AM technical capabilities. AM production time is assumed to be deterministic and does not consider build failure probability, build chamber capacity, part size, part complexity and post-processing requirements. This research is the first study to link realistic spare part demand characterization to AM supply chain design using quantitative modeling.
Citation:
Journal of Defense Analytics and Logistics
PubDate:
2021-09-14
DOI: 10.1108/JDAL-08-2020-0016
Issue No: Vol.
5
, No.
2
(2021)
- Journal of Defense Analytics and Logistics
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