CBM+ elements can be categorized into two primary categories—business/management and technical subgroups within these two categories. All the CBM+ elements contribute to the development of the maintenance plan across the whole life cycle of the weapon system or platform.
DoD maintenance of Materiel policy requires minimizing requirements for support equipment, including test, measurement, and diagnostic equipment. Maintenance programs for military materiel must utilize diagnostics, prognostics, and usage management techniques in embedded and off-equipment applications when feasible and cost effective.
Maintenance programs must provide the organic maintenance workforce with the range of technological tools necessary to enhance capabilities e.g., interactive technical manuals, portable maintenance aids, access to technical information, and serial item management, to properly equip the workforce, and to provide adequate technical and administrative training
DoD is in the process of publishing a formal policy for institutionalizing the CBM+ strategy as an element of the CPI initiative. CBM+ is a strategy to apply and integrate appropriate processes, technologies, and knowledge-based capabilities to increase operational availability and reduce total life-cycle costs by improving maintenance effectiveness and responsiveness.
CBM+ is based on performing maintenance only when there is evidence of need obtained from real-time assessments, embedded sensors, or external measurements.
CBM+ uses a system engineering approach to collect data and feed the decision-making process for operations and weapon system acquisition and sustainment.
DoD activities must establish a CBM+ environment for the maintenance and support of weapon systems by establishing appropriate processes, procedures, technological capabilities, information systems, and logistics concept.
The implementation of the CBM+ strategy in DoD maintenance organizations should not be construed as primarily the application of new methods and technologies. The basis for CBM+ is more precisely a focus on improving the business process of maintenance with the principal objective being improved operational performance as a result of increased maintenance effectiveness in terms of greater productivity, shorter maintenance cycles, increased quality of the process, and better use of resources.
DoD instructions require PMs to optimize operational readiness through affordable, integrated, embedded diagnostics and prognostics, and embedded training and testing; serialized item management; automatic identification technology AIT) and iterative technology refreshment.
In support of these requirements the TLCSM concept should be used as a vehicle for ensuring the elements of CBM+ are fully considered as early as possible in the acquisition life cycle of a weapon system or equipment.
CBM+ should be viewed as an element of TLCSM, emphasizing an early focus on sustainment within the system life cycle and part of a comprehensive view of all logistics activities associated with the fielding, sustainment, and disposal of a DoD weapon system or equipment across its life cycle.
There is a close relationship between CBM+ and Reliability Centered Maintenance RCM. RCM analysis to determine the criticality of equipment failures relative to equipment availability and the importance of the equipment to accomplishing the organization’s mission.
RCM also provides rules for determining evidence of need for CBM. Recent advances in technology, such as sensing hardware, electromechanical interfaces, data accumulation, modeling and simulation, wireless communications, and equipment health monitoring systems, can significantly improve system safety, reliability, and affordability. When implemented effectively in an integrated fashion, these and other CBM+ capabilities can improve maintenance performance and reduce funding and personnel requirements.
RCM is a logical, structured process for determining the optimal failure management strategies for any system, based upon system reliability characteristics and the intended operating context. RCM defines what must be done for a system to achieve the desired levels of safety, environmental soundness, and operational readiness at the best cost.
Specifically, RCM identifies the concepts and methods needed to select technically appropriate maintenance actions, such as predictive and preventive tasks that will prevent failure. RCM also identifies default strategies, such as failure finding tasks, engineering redesigns, and changes to operating procedures.
“If maintenance is ensuring that physical assets continue to do what their users want them to do; then, RCM is a way to determine what must be done to ensure that any asset continues to do what.
For example, the Naval Air Systems Command NAVAIR defines RCM as “an analytical process to determine the appropriate failure management strategies to ensure safe operations and cost-wise readiness.”
RCM analysis considers the failure process and related reliabilities of equipment, the severity of the related consequences of failures, and the cost effectiveness of various options to deal with failure.
In the context of RCM, there are essentially two types of maintenance: proactive and corrective. These have been presented using different terminology over the years.
Essentially, proactive maintenance actions are taken to preserve functionality often protecting safety or reducing the cost of repair and reduce unplanned downtime or impacts to mission performance. It should be noted that proactive actions by their nature require some level of investment such as to analyze, inspect, refurbish, and replace above just the correction of the failures.
The RCM process evaluates the trade-off between this investment and the overall cost. Corrective maintenance, on the other hand, responds to failures after they occur.
This may be the most effective approach for many types of equipment when the consequences of failures are acceptable or unpredictable. In a “failure management strategy,” RCM determines the proper balance between these planned and unplanned activities.
DoD’s efforts to transition from the current reactive and time-driven strategies for equipment maintenance account for current approaches have become both cost prohibitive and less than optimal in meeting today’s operational availability needs.
RCM identifies actions that, when taken, will reduce the probability of failure and are the most cost effective. One option of RCM is to choose to execute CBM actions. Once a possibility of failure is identified, it can be analyzed to determine if CBM is technically appropriate and effective.
Many types of equipment will show detectable signs of impending failure before the equipment actually fails. If an inspection of some kind can discover the deterioration between the time it is first detectable and the time when functional failure occurs , then there is an opportunity to avoid the failure.
Must establish interval to determine how often a CBM task is performed and when action must be taken to correct the impending failure. By employing CBM+ capabilities, system operators and their maintenance support team are made aware of pending failures in advance, so they are able to accomplish appropriate actions to prevent the loss of use and cost related to experiencing the actual equipment failure. It is this predictive aspect of CBM+ that clearly distinguishes this strategy from traditional approaches to maintenance in the DoD.
Successful, long-term reliance on the CBM strategy is greatly enhanced through implementation of CBM+ initiatives for improving weapon system and equipment maintenance. If CBM+ is implemented, there must be a high degree of confidence on the part of users and customers that this effort will reliably produce maximum equipment availability at a reduced cost.
The predictive capabilities instituted under CBM+ must consistently and accurately result in fewer unplanned failures, generate fewer unnecessary maintenance actions, and reduce overall costs as compared to the more traditional strategies.
As weapon systems and equipment have become more complex, the patterns of failure and the difficulty of predicting failures have also become more complex. The need to prevent or predict failures, particularly when human safety is involved, has prompted maintenance and operational managers to look for new types of failure management, particularly in the area of predictive assessment.
In some cases, it is possible to identify the potential failure condition and associated interval relatively easily when subject matter experts are asked the right questions. The focus on predicting rather than waiting for failure is based on the idea that many failures give some type of warning or show some detectable characteristic prior to the actual failure event.
CBM is used to address the capability to detect or predict deterioration or failure in advance of the actual event and to take appropriate action once there is reasonable certainty that the degradation is likely to occur in a particular time frame. RCM provides a structured and easily understandable process for determining if maintenance actions should be undertaken and when such actions are technically appropriate.
The RCM analytical approach helps the maintenance manager in identifying potential failures and supporting the selection of viable courses-of-action.
RCM tools help define the optimal failure management strategies and provide the inputs to construct the business case for implementation of the designated CBM+ strategy.
CBM+ builds on the foundation of RCM, but complements and expands on RCM by applying a broad spectrum of procedures, capabilities, and tools to improve execution of the maintenance analysis process.
CBM+ is not a process; it is a comprehensive strategy to select, integrate, and focus a number of process improvement capabilities, thereby enabling maintenance managers and their customers to attain the desired levels of system and equipment readiness in the most cost-effective manner.
CBM+ strategy includes a number of capabilities and initiatives, some procedural and some technical, that can enhance the basic RCM tasks. In this way, CBM+ enables a more effective RCM analysis.
If the RCM analysis suggests revision of maintenance tasks, then the maintenance manager should accomplish an assessment of how CBM+ capabilities may be applied to support the revised maintenance task procedures. Often, the revised tasks require fundamental changes to the maintenance strategy such as transition from time cycle repair intervals to CBM.
In other cases, application of sensor capability or diagnostic digital tools may be in order. If the proposed revisions are significant in terms of procedural changes or cost, a formal BCA may be necessary to justify the increased resource or time investment.
CBM solutions are selected based on the frequency and impact of the failure modes; the ability to employ some form of automated status sensors or other CBM+ technologies; and the expected performance, safety, or cost benefit of investing in
CBM+ capabilities ensure maintainers can identify and respond to deteriorating equipment conditions more effectively, without having to wait for a failure. CBM+ not only emphasizes a different approach, it also allows a net reduction in the amount of maintenance performed, which affects all the associated logistics elements, including parts and other footprint factors.
Clearly RCM and CBM+ have a mutually beneficial relationship. From a weapon system or equipment perspective, operational utility management of equipment without RCM analysis becomes technology insertion without a justified functionality. Conversely, collection of aggregated or platform-centric operational data without an understanding of which failure modes are consequential, and which ones are not, and the most effective course-of-action, can lead to wasted effort and unnecessary expenditure of resource
1. What is the impact on the following areas?
A CBM+ capability can provide the source data and analytical capability to determine projected RUL, repair/replace decisions, maintenance task frequency, etc. In defining the scope of the BCA ensure that any RCM and diagnostic/trending data is used to define assumptions and establish a system/component maintenance/replacement MOEs baseline from which the overall CBM+ capability cost and benefit can be assessed. For each of the following areas identify specific MOEs and metrics that are appropriate to the proposed CBM+ capability: Maintenance Planning; Manpower and Personnel; Supply Support; Support Equipment; Computer Resources Support; Facilities; Packaging, Handling, Storage, and Transportation; Design Interface; and Disposal.
2. What is the impact on total life cycle cost, including disposal?
The CBM+ BCA cost element structure should ensure that the desired costs and levels of detail are defined and analyzed to support the proposed CBM+ capability. Cost drivers should be clearly defined and will vary depending on the CBM+ capability. Hardware and software costs are primary elements regardless of the life cycle phase and will vary in scope depending on the CBM+ capability being considered (e.g., sensors, diagnostics, prognostics, etc.) . Provide a suggested cost element structure and definitions, as well as related references for use in defining your cost element structure.
3. How will fuel conservation be affected?
If the primary CBM+ capability is focused on energy conservation or fuel management, your CBM+ capability should be evaluated considering areas such as: fuel sensors/monitoring; real time fuel status; accuracy of fuel data; data transfer; fuel supply management; and system interfaces. The CBM+ BCA should identify the potential change to fuel usage and fuel management at all levels of the operational and logistics chain. Also consider possible operational benefits for improved fuel management, distribution, manning impacts, and system performance Impacts.
4. Will use of analytic techniques to predict failure or reduced performance levels affect scheduled maintenance and major replacement strategies?
Identify specific analytical tools, their projected accuracy, and their specific implementation (incremental). Utilize existing analyses, RCM studies, and historical data/information (e.g., failure data from VAMOSC) to establish a baseline for the analysis.
5. Are there incremental performance levels?
Identify the planned CBM+ capability acquisition strategy and define how it will fit with the acquisition strategy of weapon system it supports. Define the CBM+ increments as clearly as possible and ensure boundaries and interfaces with existing logistics, Command and Control, and/or weapons systems are adequately described in relationship to the CBM+ MOEs and metrics.
6. What changes will be required for operator and maintenance personnel? And systems?
Identify known impacts to the CBM+ capability, and its parent system, to ensure that the appropriate qualitative as well as quantitative MOEs are included. These should include defined impacts to the system’s operation and maintenance, policy, changes to tactics, techniques and procedures and personnel.
7. How will the repair/replace decision be affected?
When the BCA is focused on a specific system/sub‐system or component, ensure that the scope, cost elements, and MOEs are tailored accordingly. Utilize existing RCM, cost and historical data, projected RUL estimates, any phased CBM+ capability increments, and planned system/subsystem or component enhancements, wherever possible.
8. Will the system/equipment modernization plan be affected and if so how?
Identify those system/sub‐system and/or components where the projected CBM+ capability will have a direct or indirect affect on a planned modernization improvement.
9. How will the CBM+ capability impact integration with other DoD systems?
The CBM+ BCA should identify the specific systems for which the CBM+ capability will have a direct interface or integration requirement. These areas should be clearly defined in the assumptions and include the type of interface (hardware or software), timing for the connection and all related investment and sunk costs associated with the integration. In cases where an interfacing system has been fielded, ensure that the investment costs are adequately addressed in assumptions to either include them in the analysis or if they are unknown, note that they are not included.
10. How will the CBM+ capability impact service life margins?
In cases where the primary purpose of the CBM+ BCA is to determine the effect on a weapon system’s service life, ensure that the system is properly defined and all RCM and historical data/information (e.g., Performance and failure data from Visibility and Management of Operating and Support Costs (VAMOSC). VAMOSC is utilized to define baseline MOEs and related costs.