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State of Reliability

I commend for your reading an important new memo issued on June 30, 2010 by the Director of Operational Test & Evaluation (DOT&E) entitled “State of Reliability” which was written “to…

State of Reliability


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Bill Kobren

I commend for your reading an important new memo issued on June 30, 2010 by the Director of Operational Test & Evaluation (DOT&E) entitled “State of Reliability” which was written “to underscore the importance of system reliability as a major problem for Department of Defense (DoD) acquisitions.” Several noteworthy quotes from the memo, of which there are many, include:


·         “Poor reliability is a problem with major implications for cost.”

·         “…we have an opportunity to change system development to substantially reduce fielded system sustainment costs.”

·         Sustainment costs have five to ten times more impact on total life cycle costs than do RDT&E costs.”

·         “Unreliable systems have higher sustainment costs because, quite plainly, they break more frequently than planned.”

·         “If we improve system reliability in development it will reduce sustainment cost. Studies…indicate at least a seven-fold payback for this up-front investment in better reliability.”

·          “Poor reliability leads to higher sustainment costs for replacement spares, maintenance, repair parts, facilities, staff, etc.”

·         “Poor reliability hinders warfighter effectiveness and can essentially render weapons useless.”

·         “The essential issue of reliability is that it competes with achieving more operant capabilities. A reliable system is sturdy. It weighs more. It is more expensive.”

·         “We know the problem persists. We know that it results in higher costs and less effective systems. We know more stringent engineering is required to deliver reliable products.”


The memo goes on to state that “industry must be made aware that all our contracts will require, at a minimum, the system engineering practices of ANSI-GEIA STD-0009” Reliability Program Standard for Systems Design, Development and Manufacturing…to “ensure a systems level approach to identify and mitigate failure modes until requirements are met.” Further information on this memo is also available in an Inside Defense article entitled, “DOT&E Chief Decries Weapons' Reliability Rates; Urges Adherence To Key Standard.”


As key proponents for highly reliable systems, we as Life Cycle Logsitcians know that DoD already has a mandatory Materiel Reliability Key System Attribute (KSA) requirement as part of their four required Life Cycle Sustainment Outcome Metrics. This is the measure of the probability that a system will perform without failure over a specific interval. Reliability must be sufficient to support the warfighting capability need, and in it’s most basic form is defined as Mean Time Between Failures (MTBF) = (Total Operating Hours / Total # of Failures). Keep in mind, of course, that DoD also mandated an Ownership Cost KSA to provide balance to the sustainment solution by ensuring that the Operations and Support (O&S) costs associated with materiel readiness are also considered in making decisions. At the end of the day, sustainment solutions should not simply be availability and reliability "at any cost".


The memo rightly goes on to point out that “the most important reaction to this problem…was to include reliability in system design at its onset.” While it is critical to inculcate reliability into systems engineering during design and development, it’s important to remember that continuous modernization strategies, reliability improvement programs, obsolescence mitigation initiatives, and incentivization of reliability gains can and must also be part of long-term product support and sustainment as well. Time and again over the last decade, successful Performance Based Life Cycle Product Support (PBL) support and sustainment strategies have achieved significant performance gains by incentivizing investment in and metrics to achieve major reliability improvements, increasing MTBF and “time on wing” (steaming hours, miles driven, flying hours, etc). Further information and examples are available in:


·         Performance Based Logistics: A Program Manager's Product Support Guide

·         DAU LOG 235 Performance Based Logistics (Part A)

·         DAU LOG 236 Performance Based Logistics (Part B)


Further key and very helpful reliability references and resources can be found in the:


·         DoD Life Cycle Sustainment Outcome Metrics

·         Reliability, Availability & Maintainability (RAM) Special Interest Area

·         Reliability section of the Logistics Community of Practice

·         DoD Reliability, Availability, Maintainability-Cost (RAM-C) Report Manual

·         DAU LOG 103 Reliability, Availability and Maintainability (RAM) course