1 Copyright © 2012 by ASME Proceedings of the ASME 2012 International Design Engineering Technical Conferences & Computers and Information in Engineering Conference DFMLC 2012 August 12-15, 2012, Chicago, IL, USA DETC2012-71554 MODELING THE OBSOLESCENCE OF CRITICAL HUMAN SKILLS NECESSARY FOR SUPPORTING LEGACY SYSTEMS Peter Sandborn, Varun J. Prabhakar, and Abisola Kusimo CALCE Center for Advanced Life Cycle Engineering Department of Mechanical Engineering University of Maryland College Park, MD 20742 ABSTRACT Obsolescence of human skills impacts the support of long field life systems. Human skills obsolescence is a growing problem for organizations as they try to estimate and mitigate the effects of an aging workforce with specialized (and possibly irreplaceable) skill sets. Difficulties with skills obsolescence have been reported in a number of industries including industrial controls, aerospace, and military systems, all product sectors that must support critical systems for 20-30 years or longer. Common workforce planning models do not generally address the obsolescence of skills. Rather, they implicitly assume lost human resources are always replenishable. Nearly all of the existing research associated with the obsolescence of skills focuses on the opposite of the problem addressed in this paper, i.e., workers have skills that are obsolete and therefore need to be retrained in order to be employable. Alternatively, this paper addresses the lack of workers with the necessary skill set and the inability to replace them. This paper describes a model for the obsolescence of skills and skilled worker retention. This research provides a way to quantitatively address the problem of skills obsolescence and provides a basis upon which to estimate the cost of future system support. Keywords: Maintenance, experience, resources, hiring rate, obsolescence, DMSMS, workforce planning 1 INTRODUCTION Manufacturing and support organizations wish to have a secure skill pool that allows for full functionality and efficiency; however in reality the skill pool, skill level and the number of available employees tends to fluctuate, requiring careful management and forecasting to ensure that overall support is not disrupted or delayed. There are many types of mission, safety and infrastructure critical systems that have very long field support lives. Examples include military systems, industrial and transportation control systems, and communications infrastructure. Technology and part obsolescence are common problems faced by these systems [1], e.g., the inability to procure spare parts to maintain the systems. This problem is commonly referred to as Diminishing Manufacturing Sources and Material Shortages (DMSMS). Obsolescence, however, is not solely a hardware problem; it also impacts software [2] and the human skills necessary to maintain long field life systems. Human skills obsolescence is a growing problem for organizations that must support mission, safety and infrastructure critical systems as they try to estimate and mitigate the effects of an aging work-force with specialized (and possibly irreplaceable) skill sets. In the context of human skills, “obsolescence” implies that the replenishment of skills is not possible or partial at best. If the skills are replenishable, multiple new hires may be needed to reproduce the level of work of each experienced employee that leaves the organization. The motivation behind the research described in this paper was the age distribution of engineers supporting a legacy control system used in the chemical and material production industry. The mean age of employees is currently 56 and increasing as it has been difficult to retain new people to support the legacy system as younger employees relocate to other sectors and job opportunities that they perceive as having better long-term job prospects. 1 Similar difficulties have been reported in a number of industries including the Healthcare Industry [3] and other enterprises [4]. The problem is particularly relevant with organizations that must support critical systems for long periods of time, e.g., 20-30 years or longer (so called sustainment- dominated systems, [5-6]). With many employees approaching the average retirement age, a general hiring rate model for replacement and a human support risk cost-model was needed to assess the severity of the problem. The situation posed a major question for the company, how will the obsolescence of skills and the possible inability to replace these skills affect the cost of supporting the legacy system for another 10-20 years? 1 This paper does not address the particular reasons that the retention of younger engineers is insufficient to replenish the current skills pool.