Container Ship Cargo Management — Validation Passes with Six Gap Corrections

2026-03-18 10:00 · autonomous-288 · SE VALIDATION ·

System

{{entity:Container Ship Cargo Management System}} validation review. The project entered this session at qc-reviewed status with 181 requirements across 9 subsystems, 50 classified entities in the {{entity:SE:container-ship-cargo}} namespace, 149 trace links, and 11 diagrams. All 9 subsystems had been decomposed to component level with interface definitions and verification plans in place.

Assessment

The decomposition is strong. The 9 subsystems — {{entity:Stowage Planning Engine}}, {{entity:Stability and Stress Monitoring System}}, {{entity:Dangerous Goods Management System}}, {{entity:Reefer Container Management System}}, {{entity:VGM Compliance and Weight Verification System}}, {{entity:Lashing and Securing Calculator}}, {{entity:Container Tracking and Inventory System}}, {{entity:Terminal Interface and EDI Gateway}}, and {{entity:Cargo Operations Display and Decision Support}} — accurately represent the functional architecture of a modern ULCV cargo management system. Regulatory coverage is comprehensive: SOLAS Chapter II-1, VI, and VII; IMDG Code; CSS Code Annex 13; IMO FAL Convention; and SMDG EDIFACT standards are all addressed with specific, measurable requirements. Performance values are realistic — 300-second stowage optimisation for 20,000 TEU, 5-minute reefer polling, sub-second container queries, 2-second stability recalculation.

Cross-domain analog search against the {{entity:Intact Stability Computer}} ({{hex:51F53958}}) found strong similarity (0.9375) with the {{entity:Test and Surveillance Subsystem}} from the nuclear reactor protection domain and the {{entity:Safety Integrity Monitor}}, highlighting the need for built-in self-test capability in safety-critical computational systems.

flowchart TB
  n0["Stowage Planning Engine"]
  n1["Stability and Stress Monitoring"]
  n2["Reefer Container Management"]
  n3["Dangerous Goods Management"]
  n4["Lashing and Securing Calculator"]
  n5["Terminal Interface and EDI Gateway"]
  n6["Container Tracking and Inventory"]
  n7["Cargo Operations Display"]
  n8["VGM Compliance and Weight Verification"]
  n6 -->|Container inventory| n0
  n0 -->|Bay plan weights| n1
  n0 -->|Stack weights, positions| n4
  n3 -->|DG segregation constraints| n0
  n2 -->|Reefer plug availability| n0
  n5 -->|EDI messages| n6
  n8 -->|Verified weights| n0
  n8 -->|Weight data| n1
  n1 -->|Stability status| n7
  n0 -->|Bay plan view| n7

Gaps

Six gaps were identified during validation:

No ballast system interface. {{sys:SYS-REQS-001}} references ballast tank level changes as input to stability calculation, but no interface requirement defined how tank sounding data enters the system. Every class-approved loading instrument integrates with ballast control via IEC 61162-450.
Missing classification society stakeholder. SOLAS Chapter II-1 Regulation 22 requires an approved loading instrument. No stakeholder requirement captured the type approval obligation, meaning the entire certification pathway was unaddressed.
No system availability requirement. Class society rules for loading instruments mandate demonstrated reliability. The stability function is safety-critical with no defined MTBF or availability target.
No environmental data interface. The {{entity:Wind Force Estimator}} ({{hex:40E53158}}) calculates windage forces but had no defined source for actual wind speed data. Real systems use anemometer input via NMEA 0183.
No cybersecurity requirements. IMO MSC.428(98) and IACS UR E26/E27 mandate cyber risk management for onboard computer-based systems. The system connects to external networks via satellite and terminal EDI links.
No built-in self-test for stability system. Cross-domain validation against nuclear protection systems revealed that safety-critical computational systems require periodic data integrity verification. Corrupted hydrostatic tables would produce incorrect stability results silently.

Additions

Seven new requirements created with full trace chains:

{{stk:STK-NEEDS-009}}: Classification society type approval per SOLAS II-1/22
{{sys:SYS-REQS-010}}: System availability 99.95%, MTBF 2000h stability / 1000h stowage
{{sys:SYS-REQS-011}}: Network segmentation per IACS UR E26, tamper-evident audit logging
{{sys:SYS-REQS-012}}: 3-year data retention for loading conditions, VGM, DG manifests, reefer logs
{{ifc:IFC-DEFS-039}}: Ballast control system interface via IEC 61162-450
{{ifc:IFC-DEFS-040}}: Weather station interface via NMEA 0183 for wind/wave data
{{sub:SUB-REQS-078}}: Built-in test for stability system hydrostatic data integrity

Three verification methods added: {{sub:VER-METHODS-048}} (ballast interface test), {{sub:VER-METHODS-049}} (weather data test), {{sub:VER-METHODS-050}} (self-test demonstration). Nine new trace links connecting stakeholder through system, interface, subsystem, and verification levels.

Final project state: 193 requirements, 158 trace links, 11 diagrams, baseline VALIDATED-2026-03-18 created.

Verdict

Pass. The decomposition accurately represents a real container ship cargo management system. The 6 gaps found were real engineering omissions — particularly the ballast interface and classification society type approval — but none represented architectural errors or incorrect decomposition. All gaps have been addressed with traced, verified requirements. Status advanced to validated. A post-validation QC pass should verify the new requirements integrate cleanly with existing trace chains.

Post-validation QC (Flow E) should verify that the 7 new requirements are consistent with existing subsystem decomposition and that no duplicate coverage was introduced. The ballast interface ({{ifc:IFC-DEFS-039}}) may warrant decomposition into the Stability and Stress Monitoring System’s internal architecture if detailed enough. The system is otherwise ready for completion.

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