Modeling and Analysis of the Rotor Blade Refurbishment Process at the Corpus Christi Army Depot
AbstractMuch of the Army’s equipment is coming to the end of its planned life cycle. At the same time, the Department of Defense and the Army are facing severe budget reductions for the foreseeable future. As a result, the planned modernization and acquisition of new equipment will be delayed. The Army is now forced to keep and maintain current equipment as opposed to retiring old systems and buying new ones. With the increased investment in the current systems, the organizations and depots that maintain and refurbish the Army’s equipment are becoming increasingly valuable assets. Corpus Christi Army Depot (CCAD) is the Army’s only facility for repair and overhaul of rotary wing aircraft. CCAD receives approximately 10 rotor blades per day for the Black Hawk helicopter. Each blade is routed through a detailed inspection and rework process consisting of approximately 67 sequential operations which take approximately 45 days per blade. Recently CCAD has expanded and reorganized the rotor blade refurbishment facility which provides an opportunity to re-examine processes, adjust positioning of work stations, and improve efficiency. In this research we develop a discrete-event simulation model of the CCAD rotor blade refurbishment process in order to identify inefficiencies and examine “what if” scenarios to improve key performance metrics. The key performance metrics used to analyze model input include throughput, work in progress, mean queue time, mean queue size, and workstation utilization. The baseline model revealed that there were two crucial bottlenecks that severely limited the throughput and overall performance of the refurbishment process. Adjusting the capacities of these workstations was very effective in reducing the number of blades in WIP and reducing the impact of the queues in front of these stations, but failed to increase the throughput to the desired amount. Additionally, we found that the loss of one whirl tower’s production would not be a significant factor for CCAD’s performance in terms of throughput since operating with only one whirl tower did not significantly impact metrics of interest for the process.
Allahverdi, A. and Soroush, H. (2006). The significance of reducing setup times/setup costs. European Journal of Operational Research, 187(3):978-984.
Department of the Army. (2008, April). Army Depot Maintenance Enterprise Strategic Plan. Retrieved from http://www.acq.osd.mil/log/mpp/plans_reports/Enc_1_Final_Army_DMESP_061308.pdf
Department of the Army. (2014, February). Maintenance Policy & Programs. Retrieved from http://www.acq.osd.mil/log/mpp/
Global Security. (2011, May). Corpus Christi Avaition Depot. Retrieved from http://www.globalsecurity.org/military/facility/corpus-christi.htm
Ignizio, J. P. (2009). Running a Factory: In Two Dimensions. Optimizing factory performance: cost-effective ways to achieve significant and sustainable improvement. New York: McGraw-Hill.
Johnson, D.J. (2005). Converting assembly lines to assembly cells at sheet metal products: Insights on performance improvements. International Journal of Production Research, 43(7):1483-1509.
Li, J., Blumenfeld, D.E., Huang, N., & Alden, J.M. (2009). Throughput Analysis of Production Systems: Recent Advances and Future Topics. International Journal of Production Research , 47(14): 3823-851.
Li, L., Chang, Q., & Ni, J. (2009). Data driven bottleneck detection of manufacturing systems. International Journal of Production Research, 47(18): 5019-5036.
Luh, P.B., Zhou, X., & Tomastik,R.N. An Effective Method to Reduce Inventory in Job Shops. IEEE Transactions on Robotics and Automation, 16(4): 420-24.
Parnell, G., Driscoll, P., & Henderson, D. (2011). Decision making in systems engineering and management (2nd ed.). Hoboken, N.J.: Wiley.
Vergara, H., and Kim, D. (2009). A new method for the placement of buffers in serial production lines. International Journal of Production Research, 47(16): 4437-4456.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).
The copyediting stage is intended to improve the flow, clarity, grammar, wording, and formatting of the article. It represents the last chance for the author to make any substantial changes to the text because the next stage is restricted to typos and formatting corrections. The file to be copyedited is in Word or .rtf format and therefore can easily be edited as a word processing document. The set of instructions displayed here proposes two approaches to copyediting. One is based on Microsoft Word's Track Changes feature and requires that the copy editor, editor, and author have access to this program. A second system, which is software independent, has been borrowed, with permission, from the Harvard Educational Review. The journal editor is in a position to modify these instructions, so suggestions can be made to improve the process for this journal.