C-5 TNMCM study II: realistic metrics to drive operational decisions: in order to blueprint an exportable methodology, the study team developed and utilized the Hierarchical Holographic Model and a ranking and filtering process. This overall process is suitable for complex problem modeling and is exportable to other weapon systems.

Introduction

Aircraft maintenance has been and continues to be a challenging, complex task involving a delicate balance of resources to include personnel, equipment, and facilities. Adding to this challenge is the fact that the balancing act occurs in a very hectic environment where the United States Air Force flies 430 sorties per day in support of Operation Iraqi Freedom and Enduring Freedom. And somewhere in world, a mobility aircraft takes off approximately every 90 seconds. (1) At the same time, the number of airmen supporting our aircraft is declining. "Since 2001 the active duty Air Force has reduced its end-strength by almost 6 percent but our deployments have increased by at least 30 percent, primarily in support of the Global War on Terror." (2) This reduction in personnel is part of the Air Force process of drawing down the total force by approximately 40,000 people, with many of these cuts in aircraft maintenance career fields. Also adding to the growing maintenance workload is an aircraft fleet which now averages almost 24 years old, with the average still increasing. (3)

Background

When it comes to aircraft maintenance, the Air Force depends on metrics to gauge whether or not we are measuring up to the standard and succeeding in our maintenance efforts. One of the most recognized metrics is the total not mission capable maintenance (TNMCM) rate. Air Force Instruction (AFI) 21-101 describes TNMCM as "perhaps the most common and useful metric for determining if maintenance is being performed quickly and accurately." (4)

Although a lagging type indicator, it is one of several key metrics followed closely at multiple levels of the Air Force. Over the last few years, the Air Force TNMCM rate increased across many platforms. TNMCM discussions by Air Force leadership ultimately resulted in the Air Force Materiel Command Director of Logistics (AFMC/A4) requesting the Air Force Logistics Management Agency (AFLMA) to conduct an analysis of TNMCM performance with the C-5 Galaxy aircraft as the focus. AFLMA was commissioned to conduct an analysis of C-5 TNMCM performance to identify root causes, indicators, and potential corrective actions to bring TNMCM within standard, the intent being to export the methodology and any lessons learned to other weapon systems.