System Requirements Review Process

Understanding the System Requirements Review in Defence Engineering

The System Requirements Review (SRR) represents one of the most critical milestones in any defence engineering programme. This formal technical review serves as the gateway between the conceptual design phase and the preliminary design phase, ensuring that all stakeholder requirements have been properly captured, analysed, and documented before significant engineering resources are committed to detailed system development.

For defence contractors and engineering firms operating across Atlantic Canada, including those supporting projects at CFB Halifax, CFB Greenwood, and Irving Shipbuilding's facilities, mastering the SRR process is essential for successful programme execution. The complexity of modern defence systems—from naval combat systems to aerospace platforms—demands a rigorous, systematic approach to requirements management that begins with a comprehensive SRR.

At its core, the SRR validates that the functional and performance requirements derived from the customer's operational needs are complete, consistent, and achievable within the constraints of cost, schedule, and available technology. This review typically occurs approximately 12-18 months into a major defence acquisition programme, though timing varies based on programme complexity and contractual requirements.

Key Objectives and Success Criteria for the SRR

A successful System Requirements Review must accomplish several fundamental objectives that collectively demonstrate programme readiness to proceed into preliminary design. Understanding these objectives enables engineering teams to prepare comprehensive review packages that satisfy both customer expectations and internal quality standards.

Primary Objectives

• Requirements Traceability: Demonstrating clear, bidirectional traceability from operational requirements through functional requirements to system-level specifications

• Completeness Verification: Confirming that all customer requirements have been addressed and that no critical requirements have been overlooked or misinterpreted

• Feasibility Assessment: Establishing that the proposed system architecture can realistically achieve all specified performance parameters

• Risk Identification: Identifying technical, schedule, and cost risks associated with requirements and proposed mitigation strategies

• Interface Definition: Documenting all external and internal interfaces with sufficient detail to support subsequent design activities

Quantifiable Success Criteria

Defence programmes typically establish specific metrics for SRR success. Industry standards suggest that a minimum of 95% of all functional requirements should be fully defined and traceable at SRR. Additionally, no more than 5% of requirements should carry unresolved TBD (To Be Determined) designations, and those that do must have documented plans for resolution with specific target dates.

For programmes governed by Canadian Defence procurement regulations, the SRR must also demonstrate compliance with applicable standards including ITSG-33 for security requirements, CDRL (Contract Data Requirements List) specifications, and relevant NATO STANAGs where interoperability is required.

The SRR Process: A Phased Approach

Executing a successful System Requirements Review requires careful planning and execution across multiple phases. Engineering teams in Nova Scotia and throughout the Maritime provinces working on defence contracts must navigate this process while coordinating with prime contractors, Department of National Defence representatives, and various subcontractors.

Phase 1: Pre-Review Preparation (8-12 Weeks Prior)

The preparation phase establishes the foundation for a successful review. During this period, the engineering team must complete several critical activities:

• Finalise the System Requirements Specification (SRS) document, typically ranging from 200-500 pages for complex defence systems

• Complete requirements verification matrices demonstrating traceability to source documents

• Develop preliminary technical performance measures (TPMs) with threshold and objective values

• Prepare risk assessment documentation identifying at least the top 10 programme risks

• Create preliminary interface control documents (ICDs) for all external system interfaces

• Conduct internal dry-run reviews to identify and correct deficiencies before formal submission

Phase 2: Documentation Submission (4-6 Weeks Prior)

Review packages must be submitted to all stakeholders with sufficient lead time for thorough analysis. Standard practice requires submission a minimum of 30 calendar days before the scheduled review date. The documentation package typically includes:

The System Requirements Specification serves as the centrepiece document, containing all functional, performance, and design constraint requirements. This document must conform to applicable data item descriptions (DIDs), often DI-IPSC-81431 for defence programmes, and maintain consistent numbering schemes that facilitate automated traceability analysis.

Phase 3: Review Execution (2-5 Days)

The formal review typically spans two to five days, depending on system complexity. A naval combat system SRR might require a full week, while a subsystem review could be accomplished in two days. The review agenda generally follows this structure:

• Day 1: Programme overview, requirements development methodology, and operational concept review

• Day 2: Functional requirements walk-through and traceability demonstration

• Day 3: Performance requirements analysis and verification approach discussion

• Day 4: Interface requirements, risk assessment, and action item resolution

• Day 5: Summary briefings, finding consolidation, and exit criteria evaluation

Phase 4: Post-Review Actions (2-4 Weeks Following)

Following the review, the engineering team must address all Review Item Discrepancies (RIDs) and action items. Industry best practice requires closure of at least 80% of Category I findings (those affecting programme success criteria) within 30 days of review completion.

Technical Documentation Requirements

The documentation package for an SRR must satisfy stringent content and format requirements established by defence acquisition regulations. For Canadian defence programmes, these requirements often align with both domestic standards and US MIL-STD guidelines where interoperability with allied forces is a consideration.

System Requirements Specification Content

A comprehensive SRS for defence applications typically includes the following major sections, each requiring substantial technical detail:

• Section 1 - Scope: System identification, overview, and document structure (typically 5-10 pages)

• Section 2 - Applicable Documents: Referenced specifications, standards, and source documents (20-50 references typical)

• Section 3 - Requirements: The core section containing all system requirements, often comprising 60-70% of total document length

• Section 4 - Verification: Methods for verifying each requirement (inspection, analysis, demonstration, or test)

• Section 5 - Packaging: Requirements for deliverable items and documentation

• Section 6 - Notes: Background information and requirement rationale

Requirements Writing Standards

Each requirement must be written to specific standards that ensure clarity and verifiability. Defence engineering best practices mandate that requirements shall:

Be uniquely identified with a hierarchical numbering system (e.g., SRS-3.2.4.1) that supports automated traceability tools. Contain a single, testable requirement statement—compound requirements that use conjunctions like "and" or "or" must be decomposed into separate requirements.

Include quantitative performance parameters wherever possible. Rather than stating "the system shall process data quickly," a properly written requirement specifies "the system shall process input data and generate output within 250 milliseconds under nominal operating conditions."

Common Challenges and Mitigation Strategies

Engineering teams across Atlantic Canada face several recurring challenges when preparing for and executing System Requirements Reviews. Understanding these challenges and implementing proactive mitigation strategies significantly improves the probability of successful review outcomes.

Requirements Volatility

Defence programmes frequently experience requirements changes during the early programme phases. Studies indicate that 25-40% of requirements may change between programme initiation and SRR completion. To manage this volatility, engineering teams should implement formal configuration management processes early in the programme and maintain a requirements change log that tracks all modifications with full justification documentation.

Traceability Gaps

Incomplete traceability between operational requirements and system specifications represents one of the most common SRR deficiencies. Modern requirements management tools such as IBM DOORS, Jama Connect, or Polarion can automate traceability analysis and highlight gaps before formal review. Investment in these tools typically yields substantial returns through reduced rework and improved review outcomes.

Interface Complexity

Modern defence systems must interface with numerous external systems, creating significant documentation challenges. A typical naval platform might have 50-100 external interfaces requiring detailed specification. Establishing interface working groups early in the programme and developing preliminary ICDs in parallel with the SRS helps ensure interface requirements receive adequate attention.

Resource Constraints

Smaller engineering firms often struggle to allocate sufficient resources for comprehensive SRR preparation while maintaining other programme activities. Strategic partnerships with complementary firms and careful phase planning can help distribute workload effectively. The Maritime defence engineering community benefits from a collaborative ecosystem that enables resource sharing during peak demand periods.

Integration with Canadian Defence Procurement

Defence engineering firms operating in Nova Scotia must align their SRR processes with the specific requirements of Canadian defence procurement. The Department of National Defence procurement framework establishes specific expectations for technical reviews that may differ from commercial or US defence standards.

Industrial and Technological Benefits (ITB) Considerations

Major defence procurements in Canada include Industrial and Technological Benefits requirements that may influence system requirements. Engineering teams must consider how ITB obligations—particularly Value Propositions requiring Canadian content—affect system architecture decisions documented in the SRR package.

Security Classification Requirements

Defence systems often involve classified information that imposes additional requirements on the SRR process. Engineering firms must maintain appropriate facility security clearances and ensure that review documentation properly handles classified content. For Maritime-based programmes, this frequently involves coordination with the Canadian Industrial Security Directorate.

Bilingual Documentation

Depending on programme requirements, SRR documentation may require translation into both official languages. Engineering teams should factor translation timelines into their preparation schedules, as technical translation for defence applications requires specialised expertise and quality assurance processes.

Tools and Technologies Supporting the SRR Process

Modern requirements engineering relies heavily on specialised software tools that facilitate requirements capture, analysis, and traceability. Selection of appropriate tools early in the programme lifecycle establishes efficient workflows that benefit all subsequent programme phases.

Requirements management databases form the core of the technical infrastructure, providing structured storage for thousands of individual requirements while maintaining relationship links and change history. Integration with model-based systems engineering (MBSE) tools enables requirements to be linked directly to system models, providing additional validation of completeness and consistency.

Collaborative review platforms enable distributed engineering teams—increasingly common for programmes spanning multiple Atlantic Canadian locations—to conduct effective document reviews and track comment resolution. These platforms reduce the administrative burden of managing hundreds of review comments while ensuring complete traceability of all decisions.

Partner with Sangster Engineering Ltd. for Your Defence Engineering Requirements

Successfully navigating the System Requirements Review process demands deep expertise in defence engineering practices, comprehensive understanding of Canadian procurement requirements, and proven experience with complex technical programmes. Sangster Engineering Ltd. brings this combination of capabilities to defence contractors and government clients throughout Atlantic Canada.

Our team of experienced engineers understands the unique challenges facing Maritime defence programmes, from naval systems supporting the Royal Canadian Navy's fleet to aerospace applications at regional military installations. We provide comprehensive support for requirements development, technical documentation, and formal review preparation that positions programmes for successful SRR outcomes.

Contact Sangster Engineering Ltd. today to discuss how our defence engineering expertise can support your next programme milestone. Whether you require full requirements engineering support or targeted assistance with specific SRR preparation activities, our Amherst-based team is ready to deliver the professional engineering services your programme demands.

Partner with Sangster Engineering

At Sangster Engineering Ltd. in Amherst, Nova Scotia, we bring decades of engineering experience to every project. Serving clients across Atlantic Canada and beyond.

Contact us today to discuss your engineering needs.