EOC on the MAF. This first position is derived from the mission essential subsystem matrices (MESMs) that are published as an enclosure to Mission Essential Subsystem Matrices (MESMs), OPNAVINST 5442.4. The second and third positions of the EOC codes are computer generated from the first two positions of the Work Unit Code (WUC) on the MAF. INVENTORY AND READINESS REPORTING Effective management of the maintenance effort requires the following information: The degree of aircraft or equipment mission impairment The length of time the aircraft or equipment was impaired The system or subsystem that caused the mission impairment The maintenance and supply impact on the aircraft capability The SCIR system is used to monitor the mission capability of selected end items. Navy and Marine Corps aircraft that are listed in OPNAVINST 5442.4 require SCIR documentation. The work center that performs the corrective maintenance documents SCIR on the MAF concurrently with the maintenance action that caused the reduction of the equipment’s mission capability. SCIR is also used by maintenance or production control to report inventory data on both aircraft and items of SE. Both inventory and readiness data is documented on the MAF. TERMS AND CODES To help you understand the relationship between SCIR and inventory and readiness reporting, an explanation of the terms and codes that are commonly used in the SCIR system is given in the following paragraphs. The controlling custodian manages and distributes fleet assets. A controlling custodian exercises administrative control over the assignment, employment, and logistic support of aircraft. The Chief of Naval Operations (CNO) assigns the area of responsibility for each controlling custodian. Examples of controlling custodians include Commander, Naval Air Force, U.S. Atlantic (COMNAVAIRLANT) and Commander, Naval Air Force, U.S. Pacific (COMNAVAIRPAC). The reporting custodian is the activity that has primary custody of an aircraft. The reporting custodian is responsible for maintenance and readiness reporting as well as day-to-day maintenance of aircraft. Examples of reporting custodians include VF-101, VS-22, and VFA 136. Inventory codes define the reporting requirements and current status of an aircraft or equipment at the time of inventory, for example, Gain, Loss, or change in Material Condition Reporting Status. The term IN Material Condition Reporting Status (IN MCRS) (inventory code A) means that an aircraft is in the inventory system and that the aircraft requires SCIR documentation. IN MCRS is the normal status of aircraft. The term OUT Material Condition Reporting Status (OUT MCRS) (inventory codes 1 through 4) means that an aircraft is in the inventory reporting system but does not require SCIR documentation. An aircraft is placed OUT MCRS for depot-level maintenance. When an aircraft is placed OUT of MCRS, EOC code A applies to all existing SCIR discrepancies. Transaction codes describe inventory transactions. Transaction codes for inventory transactions are listed below. An inventory gain (transaction code 00) occurs when a reporting custodian receives an aircraft into its inventory. Aircraft are gained in any inventory status code category. An inventory loss (transaction code 03) occurs when a reporting custodian transfers an aircraft or strikes it from naval service. An inventory loss is documented only if the aircraft has been previously gained and is in the inventory system. Aircraft may be lost in any inventory status code category. A change in MCRS (OUT and IN) (transaction code 02) does not involve a change of reporting custodian. Aircraft are only IN MCRS if the aircraft is in OPNAV XRAY status code A. Aircraft in all other OPNAV XRAY status codes are OUT MCRS. NOTE: Each instance of aircraft or equipment gain, loss, or change in MCRS requires an update of the Equipment Master Roster (E-00). 5-19