RAM design activities start in pre-systems acquisition and continue through development, production, and beyond into operations and support.
Systems engineering is a logically sequenced, consistent set of technical activities often do not provide the balanced solution systems engineering design assessments strive to obtain. RAM prediction is any method used to assess the level of RAM that is potentially achievable, or being achieved, at any point. Achieving metrics via a RAM prediction will not ensure that the best system design is developed.
As important as it is to select the right activities, it is equally important to conduct the activities at the right time. An assessment intended to support design improvement, for example, is of little value if it is begun near or after the critical design review. For maintainability, it is of little value to require explicit levels of system testability for accurate and dependable fault detection and isolation during the design phase.
If the system does not achieve good RAM, mission performance and life cycle cost are at risk. The pressures of budget or schedule can cause Program Managers and contractors to consider reducing or eliminating RAM activities, in particular the task of ID maturation since it occurs near the end of system development just prior to technical or operational evaluation .
An objective assessment of risk and impact should be made. Specifically, any potential negative impact on the system’s ability to provide measurable increases to mission capability or operational support should be weighed against any potential short-term savings. Unless a programmatic, systems engineering and total life-cycle perspective is taken in making such decisions, the net result can be decreased mission performance and increased costs over the long term.
The RAM Case is a reasoned, auditable record to document how well a defined system supports the RAM requirements. It provides progressive assurance that RAM requirements are being developed, implemented, verified, enforced and that the requirements can be achieved.
The case evolves between the customer and supplier as the project evolves. Initially the customer is the acquisition organisation; eventually, it is subsequently the user. Reliability analyses are not an after-the-fact documentation of what resulted during the design process, but an active integral part of the design process.
The review process uses a closed-loop system that identifies each design defect, enters it into a deficiencies and serve as an accurate historical record of the design activity be of little use in achieving the requisite level of RAM if it is not conducted properly. Standards, guides, and textbooks are available that provide the correct procedure for conducting nearly every type of analysis or test related to designing for RAM.
System engineering ensures that the solution that satisfies the requirements of RAM technical considerations. Systems engineering expands the evaluation criteria to select criteria that best balance program requirements, such as system performance, total ownership cost, schedule, supportability, risk, etc. The criteria are selected based on the stated problem as well as the level and complexity of required assessments.
“What Tools are Required to Construct Complete Case Model Concept?”
1. Understand and Document User Needs and Constraints, their utilization may vary from acquisition to acquisition. Almost always there will be a need for a RAM Program Plan and often there is a strong desire to develop the RAM Rationale, but the benefit of the RAM Case may often be overlooked
2. The RAM Rationale defines the needed RAM characteristics, mission profile and use environment. The RAM Rationale identifies the RAM requirements, and their assess basis, to be documented in the request for proposal
3. The RAM Program Plan lays out the strategies, processes, resources, and organization to achieve the RAM requirements.
4. The RAM Case provides the record of how well requirements have been demonstrated at each stage of the program. The RAM Case provides the evidence that the contractor
the contractor’s evidence within request for proposal contractual documents, etc.
5. The systems engineering app roach to the acquisition process recommends technical reviews to confirm outputs of the acquisition phases and major technical efforts within the technical phases. Must Understand and Document User Needs and Constraints the following technical reviews should be conducted.
6. Initial Technical Review : Multi-disciplined technical review to support a program’s initial Program Objective Memorandum submission. This review ensures that a program’s technical baseline is sufficiently rigorous to support a valid cost estimate with acceptable cost risk, and enable an independent assessment
7. Alternative System Review: Model and expert judgment to make p reliminary RAM estimates, develop RAM Rationale, planning the RAM program. Although the RAM the activities required to achieve a reliable, available, and maintainable system. achieved RAM requirements. So without the RAM Case and the presentation of uncertainty levels is possible in terms of the contractor’s ability to satisfy the RAM requirements as defined by estimates of cost, technical, and program management subject matter experts
8. System Review: Multi-disciplined technical review that ensures that requirements agree with the customers’ needs and expectations and proceed into the Technology Development phase of the acquisition process.
9. System Requirements Review Multi-functional technical review that ensures all system and performance requirements derived from the Capability Development Document are defined and consistent with cost, schedule, risk, and other system constraints. The review determines the direction and progress of the systems engineering effort and the degree of convergence upon a balanced and complete configuration review provides the preliminary allocation of system requirements to verify that test methods and acceptance criteria, based on use of agreed-to verification methods, are incorporated into schedules, facilities requirements, manpower needs, and other programmatic imperatives.
10. Integrated Baseline Review should be conducted throughout the acquisition process identifies project milestones and resources as well as ensuring objective and rationale system measurements RAM are identified.
“Systems Engineering Work Reach System Capable User Requirements”
1. Must account for the entire service life of the system/capability acquisition.
2. Functions that systems engineering accounts for are development, manufacturing/production/construction, deployment/fielding, operation, support, training, and verification.
3. Systems engineering ensures that the correct technical tasks are accomplished during the acquisition process through planning, tracking, and coordinating.
4. Development of a total system design solution that balances cost, schedule, performance, and risk
5. Development and tracking of technical information required for decision making
6. Verification that technical solutions satisfy customer requirements
7. Development of a system that is cost-effective and supportable throughout service life
8. Adoption of the open systems approach to monitor internal and external interface compatibility for the systems and subsystems,
9. Establishment of baselines and configuration control
10. Proper focus and structure of interdisciplinary teams for system and major subsystem level design.
“Evaluate Effect of RAM Changes to System Design”
1. Determines rank ID the effects of each failure mode on system performance
2. Emphasises identification of single-point failures developing corrective actions.
3. Facilitates investigation of design alternatives
4. Consider high reliability at the conceptual stages of the design.
5. Provides a foundation for qualitative reliability, maintainability, logistics assessments
6. Provides the criteria for early planning of tests to characterize the weaknesses of the design
7. Determine basis for operational troubleshooting
8. Locating performance monitoring devices within the system.
9. Visibility of system interface features and problems
10. fault sensing test equipment or test points.
“Questions to Address Before Full Rate Production Proceeds”
1. Satisfy RAM and quality inspection and test requirements?
2. What full-rate production RAM problems are revealed during model fabrication, testing, and manufacture?
3. What specialized “burn-in,” parts screening, or other special manufacturing process required
4. Meet production reliability/quality inspection and test criteria?
5. How does the production rework and shrinkage rate for individual co-assemblies, units, etc., correlate with RAM of the production item as measured in factory acceptance tests?
6. What impact do proposed engineering changes, manufacturing changes, have on RAM?
7. Does production model conform to specified reliability demo requirements?
8. Are procedures and processes in place for anticipating diminishing manufacturing sources and finding alternative ways of supplying the affected items?
9. Are off equipment maintenance facilities, processes, tools in development?
10. System refined sufficiently to support the system in multiple operational scenarios?
“Service Life Cost Structure Components not Considered”
Inadequate support funding can affect many factors, including availability of repair parts, support equipment, and maintainer training with big mpact on RAM
1. System Operation Cost: Base cost to operate the system including paying the users, fuel for the system, and so on.
2. Distribution Cost: Cost to ship the product to its destination.
3. Information Technology Resource Cost: Often when deploying a new system, personnel will be deployed with the system and the personnel will need new computers. New complex systems will require extensive computing capability to accommodate on-board recorded data for various disciplines. Therefore no matter how simple, there will be some computing time added to the O&S costs.
4. Maintenance Cost: Costs to conduct routine maintenance, at whatever level, including compatibility using Automated Maintenance scenario tools and resources.
5. Test and Support Equipment Cost: Costs associated with developing and acquiring diagnostic equipment and tools required for the new system how to use and maintain the new system.
6. Training Cost: All systems require some level of costs to train users and maintainers on hand how to use system
7. Supply Support Cost: Costs associated with shipping spare parts, returning faulty parts to the depot for repair, etc.
8. Retirement and Disposal/Recycling Cost: Eventually the new system will reach the end of its useful life and must be appropriately discarded
9. Technical Data Cost: Developing a library of technical data is vital for any complex system and there will be costs associate with collecting, maintaining, and assessing this tech info
10. In-Service Engineering and Logistics Cost: The cost associated with the management and execution of the service life requirements.