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Reliability, Availability, and Maintainability-Cost (RAM-C) Rationale Report

ALCL 159


For MDAPs, the Program Manager will prepare a preliminary Reliability, Availability, Maintainability and Cost (RAM-C) Rationale Report in support of the Milestone A decision. This report provides a quantitative basis for reliability requirements, and improves cost estimates and program planning. This report will be attached to the Systems Engineering Plan (SEP) at Milestone A, and updated in support of the Development Request for Proposal (RFP) Release Decision Point, Milestone B, and Milestone C. The RAM-C report will also document the quantitative basis for the three elements of the Sustainment Key Performance Parameter (KPP) as well as the tradeoffs made with respect to system performance.

General Information


The RAM-C Rationale Report provides a quantitative basis for assessing the validity and feasibility of Reliability & Maintainability (R&M) performance attributes during the development of a system’s capability requirements. The RAM-C Rationale Report is typically prepared by the requiring organization (e.g., combat developer) in conjunction with the materiel developer (e.g., program office) and other stakeholders and includes a comprehensive assessment of the Sustainment KPP and other sustainment requirements, including the trade space associated with those requirements.  The RAM-C Rationale Report informs system requirements established in Joint Capabilities Integration and Development System (JCIDS) documents, (e.g., the Capability Development Document (CDD)), which in turn informs system specifications and other contract requirements.

Specific Requirements

There are numerous documents that call out the RAM-C Rationale Report. The primary ones are included below:

  • The JCIDS Manual - requires a RAM-C Rationale Report to document “the quantitative basis for the elements of the Sustainment KPP as well as the technical feasibility tradeoffs and rationale made with respect to system performance, program costs, and schedule” (para 2.5.1). 
  • For MDAPs, DoDI 5000.88, Engineering of Defense Systems, para 3.6b(2), requires the PM to “conduct a preliminary reliability, availability, maintainability, and cost rationale analysis in support of the Milestone (MS) A decision or program initiation decision (e.g., if a program enters at MS B) in accordance with the Reliability Availability Maintainability Cost (RAM-C) Rationale Report Outline guidance.”  
  • DoDI 5000.88 (para 3.6b(2)(a) and (b)) further states the analysis “provides a quantitative basis for R&M performance attributes during the development of capability requirements, including product support and operating and support cost rationale and its specific correlation with the system’s R&M attributes, ensuring the requirements are valid (e.g., support warfighter needs) and technically feasible” and will be documented in an attachment to the Systems Engineering Plan (SEP).  The RAM-C Rationale Report is updated for the Development Request for Proposal (RFP) Release Decision (DRFPRD), MS B, MS C, and the Full Rate Production (FRP) decision for programs using the Major Capability Acquisition (MCA) pathway. 
  • For programs meeting the MDAP funding threshold in and utilizing other Adaptive Acquisition Framework (AAF) pathways, refer to the governing DoD Instruction(s), Service, and/or program-specific guidance.   

RAM-C Report Outline

The Deputy Assistant Secretary of Defense for Systems Engineering, DASD(SE), maintains the 21-page RAM-C Report Outline.  The outline includes:

  • Signature Blocks for the Lead Systems Engineer (LSE), Product Support Manager (PSM), Business Financial Manager (BFM), and PM indicating the interdisciplinary nature of the report
  • Executive Summary – including an assessment of the Sustainment KPP, Key System Attributes (KSAs), and Additional Performance Attributes (APAs) based on composite model estimates and predecessor (legacy) systems
  • Introduction – including purpose and version of JCIDS documentation (e.g., CDD) the report supports, preparers, and record of changes
  • Program Information – including system description, sustainment parameters, Operational Mode Summary/Mission Profile (OMS/MP), operating environment, maintenance concept, and planning factors
  • Validation – including Operational Availability (Ao), Materiel Availability (Am), Reliability (R), and Operating and Support (O&S) Cost
  • Feasibility – including the composite system model, R&M feasibility, O&S Cost feasibility, and Ao and Am feasibility
  • Trade Studies – including sensitivity analysis of the range of R&M parameters (e.g., Mean Time Between Failure (MTBF) and Mean Down Time (MDT))
  • Summary – including results, significant degraders, top drivers, and mitigations
  • Annexes for acronyms, program documentation, references, tools, and composite model details

RAM-C Rationale Report Training Briefing 

DASD(SE)’s RAM-C Rationale Report Training Briefing identifies a 6-step process for conducting RAM-C Analysis:

  1. Initiate Analysis
  2. Form Team
  3. Gather Information
  4. Validate
  5. Assess Feasibility
  6. Conduct Trade Studies


The briefing employs a notional Unmanned Aerial Vehicle (UAV) to demonstrate concepts and methods related to the RAM-C analysis.  It cites several attributes of an effective RAM-C, including:

  • JCIDS sustainment parameters are validated and feasible
  • Program R&M engineer, product support team, and cost analyst involvement
  • KPP, KSA(s), and APA(s) support the OMS/MP, Concept of Operations (CONOPS), and maintenance and sustainment concepts
  • “the math works” showing parameters are valid
  • the composite model reflects current state of the art, comparison data, and determines feasibility
  • trade analysis illustrates trade space in the feasible region
  • the analysis is conducted early enough to influence sustainment related decisions and drive program decisions
  • demonstrates collaboration with requirements developers
  • uses the best information available
  • verifies the definitions of “failure” for KPP/KSA(s)/APA(s)
  • uses appropriate analysis techniques
  • demonstrates an understanding of the options available within the trade space and how the program used this analysis to make better sustainment decisions

Product Support Team Role

The PSM’s team should be intimately involved in preparing and reviewing the RAM-C Rationale Report.  Title 10 USC 4324(c)(2)(B) requires PSMs “ensure the life cycle sustainment plan is informed by appropriate predictive analysis and modeling tools that can improve material availability and reliability, increase operational availability rates, and reduce operation and sustainment costs.”  In turn, DoDI 5000.91 (para 4.8c(1)) requires the PSM to “work with systems engineers and users to develop the RAM-C Rationale Report to ensure supportability, maintenance, and training are incorporated into the design through early user assessments, and to incorporate user feedback into supportability planning” to “ensure sustainment thresholds are valid and feasible.”  In addition, the DASD(SE) R&M Body of Knowledge (BoK) (para 1.1.3) notes the RAM-C Rationale Report should provide the following for product support design: (a) failure mode assessment, including effects, detection, and diagnostics; and (b) initial failure and removal rate estimates for corrective and preventive maintenance to inform level of repair and spares planning. 

Linkage to the Life Cycle Sustainment Plan (LCSP)

Finally, while the RAM-C Report is an attachment to the program SEP, it also informs the program LCSP.  The DoD LCSP Outline (para 2) states, “in such acquisition deliverables as the Acquisition Strategy, Analysis of Alternatives (AoA), SEP, RAM-C Rationale Report, Concept of Operations/Operational Mode Summary/Mission Profile (CONOPS/OMS/MP), and requirement documents (Initial Capabilities Document (ICD) or Capability Development Document (CDD)), PSMs should use the insights and critical thinking embodied therein as the logical basis for the sustainment plan.”