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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.

Results of linear regression were significant in 4 of 12 analyses, suggesting that SDRs are a significant predictor of increased cannibalizations. Results of independent samples t-tests found MICAP hours were significantly higher on discrepant shipments compared to nondiscrepant shipments in all three analyses.

This research will increase awareness of the extent to which SDRs degrade aircraft readiness, and provide an opportunity for United States Department of Defense (DoD) supply chain leaders to take action to improve order fulfillment performance in their organizations.

Little research has been done investigating the impact of SDRs within the DoD, and to the best of the authors’ knowledge, no previous study has examined the effect of SDRs on military aircraft readiness metrics.

Aircraft availability (AA) is a key metric for assessing operational readiness. The declining trend in AA is a documented concern for senior Air Force leaders. This paper aims to investigate the components of non-available time and subsequently focuses on the largest and fastest growing category: not mission capable maintenance unscheduled (NMCMU). Then, utilization of aircraft platforms is examined to determine the readiness benefits of increasing available hours.

Stepwise regression is conducted on a data set of 30 aircraft platforms, consisting of 542 observations from 1998 to 2017, to reveal drivers of NMCMU. Next, utilization of aircraft platforms is examined through regression and correlation analysis of aircraft platforms and sorties or hours flown.

Regression analysis reveals drivers of NMCMU include platform type, average age of aircraft, fleet size, breaks and cannibalization. These factors explain 80.6 per cent of the variance in the data set when predicting NMCMU. Additionally, the utilization results show that when more hours are made available, 5 per cent of each new hour is used for flying. Further analysis at the individual platform level finds a strong or moderate correlation between available hours and sorties flown for 93 per cent of the platforms.

Implications from the regression analysis demonstrate there are remedies to increase AA, but many of these remedies may be costly. The utilization analysis expresses the potential readiness benefits of increasing available hours.

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.

The purpose of this study is to provide the benchmarking guideline to improve managing maintenance man-hour in producing sorties of fighter jet aircraft in the Korean Air Force by measuring relative efficiency of aircraft in a fleet.

Using actual operational data from 2014 to 2018, this paper measures the relative efficiencies of aircraft by data envelopment analysis (DEA) model. To analyze the efficiencies across different operational units and among aircraft with different attributes, non-parametric statistical techniques and tobit regression are employed.

The overall management of maintenance man-hour turns out to be 63.2% efficient compared to the best practice. Operational unit possessing aircraft with different configurations shows the poorest performance implying efficiency depends on the complexity of job processes. Identification of aircraft on the best-practice frontier indicates the efficiency is closely related with the reliability of components and the age of aircraft.

Performance of aircraft maintenance has a tremendous impact on military readiness, utilization of work force, and the quality and safety of flight operations. This study confirmed there exists plenty of room for performance enhancement and presents a reference to find a balance in the performances of maintenance practices across different installations as well as among different types of aircraft.

Application of DEA to engineering systems has been limited in literature, especially in military operations. Thus, this study presents meaningful guidelines to which fleet manager can refer to when establishing strategic maintenance plans to balance the utilization of manpower.

The authors employed the three different versions (Charnes–Cooper–Rhodes, Banker–Charnes–Cooper and slack-based measure of efficiency) of data envelopment analysis (DEA) to evaluate the comparative efficiency/inefficiency of aircraft maintenance performance during the previous 41 months in United States Air Force (USAF). As a complimentary tool, the authors also adopted Tobit regression analysis to identify factors affecting efficiencies and inefficiencies.

This paper aims to measure the relative efficiency of maintenance performances for a type of USAF aircraft in an effort to enhance aviation safety and combat readiness.

Through this study, the authors have two noteworthy findings. These are (1) an increased number of “cannibalization” (extracting necessary parts from the existing aircraft) practices tended to reduce maintenance efficiency; (2) The number of mission-capable aircraft turned out to be the most important factor for maintenance performance efficiency.

This paper is one of the first studies on aircraft maintenance that considered popular but neglected cannibalization practices as a new variable for assessing the maintenance efficiency. In addition, this paper is one of the few studies that performed a post-ad hoc analysis as a follow-up to DEA analysis.

The life span of an aircraft is usually around 30 years in the commercial aviation industry. During this time span, aircraft needs maintenance to stay in service. The cost of maintenance, repair and overhaul (MRO) activities in its pure nature is a significant portion of operations, accounting around 10 percent of all cost drivers. The purpose of this paper is to design/develop and critically assess a comprehensive model of operations at Turkish Technic – the MRO department of Turkish Airlines.

A comprehensive systems dynamics model is designed and developed to holistically represent and critically assess the different facets of MRO operations to help in analyzing various decision scenarios at Turkish Airlines.

The developed system dynamics (SD) model presented unique opportunities to test various MRO operations’ work load and aircraft fleet expansion policy alternatives. The model can also be used as a “learning laboratory” by altering various system parameters and testing different policies. The case study results suggested that MRO operations have a direct impact on the available number of airworthy aircrafts and hence, the usable fleet seat capacity; to sustain a profitable airline fleet, the airline companies should take into account the unique characteristics/needs of MRO operations for both existing and new/prospective aircrafts.

There are several SD studies in the literature focusing on the airline industry, but the MRO operations are virtually neglected in them. Hence, the proposed SD model contributed to the extant literature. The value of the developed model stems from its potential use in the critical analysis of decision scenarios as well as being leveraged as a training/learning laboratory.

One of the main factors contributing to the effectiveness of the Royal Air Force is the quality of its equipment. To be most efficient the equipment should have the highest possible performance coupled with complete reliability. Any departure from this standard of reliability must be compensated for by economy in maintainability. The high and unacceptable failure rates experienced by the Royal Air Force are discussed as are the effects on aircraft availability, mission success and flight safety. Other serious aspects are the consumption of spares, their replacement and the financial costs involved. Some failure patterns in different aircraft environments are discussed and the cause and effects of failures are examined, together with the modifications which have taken place. The paper concludes with a statement on the reliability and maintainability requirement which the Royal Air Force must have if it is to provide the maximum national insurance with its weapon systems.

The systems aspects of an uninhabited tactical aircraft (UTA) preliminary design are detailed. The study, performed at the post‐graduate level at Cranfield University, looks to investigate the feasibility of unmanned combat aircraft in a number of roles to reduce the risk to pilots and reduce life cycle costs (LCC). The scope of the work includes stealth, vulnerability, mission effectiveness, avionics, landing gear, secondary power, fuel systems, propulsion, performance and cost. The unusual depth to which the design work progressed enables insights to be gained that far exceed those available at the conceptual design phase. A Northrop Grumman concept of near‐identical configuration has subsequently reached the public domain.

The purpose of this paper is to present the development results of the overhaul melioration plan for the following aircraft types: MiG‐21Bis, G‐4 Galeb and SA‐341 helicopter. This research has been conducted based on available knowledge and extensive experience gained by performing general maintenance of the Air Force of Serbia aircraft.

A general analysis was performed by processing data collected while performing maintenance and repair procedures. The magnitude of data is based on detecting the delays and errors that occurred while going through the operational and inter‐operational stages of aircraft overhaul. On the basis of the obtained research results, a proposal for the aircraft overhaul optimization is offered.

The proposed overhaul improvement plan points out the priority steps to be taken in order to optimize the most critical features that jeopardize the quality of the aircraft overhaul process relating to organization, technology and design. Moreover, existing technical logistics have been used for providing actions to achieve the objective in focus: the all‐encompassing optimization of the above selected aircraft overhaul.

The method of the overhaul optimization has so far been applicable to the aircraft of the Army of Serbia. However, the particular methodology can be proved potentially useful and highly germane when applying to other aircraft types.

A plan to optimize the overhaul is based on a one‐year monitoring process of the aforementioned aircraft. It enables significant savings in performing overhauls within the financial realm as well as time‐wise.