When mapping AOG risk, the primary filter should be aircraft-level impact: does the absence of this component prevent dispatch or safe operation under applicable regulations and operator MELs? Price and annual spend are secondary; a low-cost sensor or minor actuator can be far more AOG-critical than an expensive cabin furnishing if the former has no approved deferral or workaround. A structured link from the maintenance program and MEL to the parts list will usually surface a much smaller subset of truly grounding components. This requires disciplined configuration control to know which parts are actually installed by tail and which configurations drive dispatch limitations. Without accurate configuration and MEL mapping, AOG risk maps quickly become misleading and overbroad.
Components with long manufacturing or repair lead times deserve early focus because they drive extended ground time when things go wrong. In aerospace-grade environments, structural parts, unique machined details, and heavily certified hardware often sit at the top of this list. Items that require significant qualification, revalidation, or first-article work with each supplier change are especially risky, since you cannot easily pivot to alternates when supply breaks. Lead times are also affected by special processes, capacity bottlenecks, and export or regulatory constraints, which may not be visible in standard ERP data. Mapping AOG risk should therefore incorporate realistic lead time and requalification windows, not only nominal vendor lead times.
Line-replaceable units that are safety-critical or tightly tied to flight-critical functions should be prioritized because they often lack permissible deferrals. Examples include flight controls, avionics, braking components, and other systems where MEL relief is limited or non-existent. Even when spares exist, low on-hand quantities combined with long repair cycle times can make these LRUs de facto AOG drivers in certain fleets or stations. The risk map should capture both the severity (does it ground the aircraft?) and the time-to-recover (how quickly can a serviceable unit be positioned?). Fleet maturity and reliability data will influence how aggressively you prioritize specific LRUs, but assumptions must be explicit and periodically reviewed.
Single-source components and parts from suppliers with fragile quality or capacity performance should move up the AOG priority list, regardless of historical usage. In regulated environments, shifting to a new source may trigger substantial qualification, documentation, and PPAP or equivalent activities, meaning that theoretical multi-sourcing is not an immediate mitigation. Parts relying on obsolete materials, legacy processes, or special licenses also contribute to fragile supply chains and elevate AOG exposure. When mapping risk, you should combine supplier dependency, qualification burden, and geographic or geopolitical risks into a simple but explicit supply fragility score. This helps separate genuine AOG risk from normal commercial risk.
Components with unique repairs, mod states, or limited serial-number interchangeability create hidden AOG risk because not every spare can support every tail. Over years of operation, incremental design changes, bulletins, and repairs can fragment interchangeability in ways that standard part-number-based planning does not capture. When a tail-specific or configuration-specific part fails, even a seemingly healthy network spare inventory may not help, leading to avoidable ground time. Mapping AOG risk effectively means linking parts to configuration and mod status, not just to a generic fleet. Where that traceability is weak, the risk map should explicitly call out this data gap rather than implying a level of control that does not exist.
Certain consumables, sealants, fasteners, and other ostensibly low-value items can be AOG-critical if they are required to close maintenance tasks that affect airworthiness. In many plants and MRO operations, these items fall outside tight planning and can be managed casually through local stores, which works until a specific spec or batch becomes unavailable. Items with narrow specification windows, limited shelf life, or mandatory batch traceability can be particularly problematic. AOG risk mapping should therefore include a minimal set of consumables and expendables whose absence has previously driven delays or that maintenance engineering labels as “task-stoppers.” Over-prioritizing everything in this category, however, dilutes focus and should be avoided.
After the initial prioritization by criticality and supply constraints, you should refine the list using fleet reliability and AOG event history. Some theoretically high-risk components rarely fail in service, while other mid-criticality parts drive frequent line disruptions due to reliability issues, nuisance faults, or diagnostic ambiguity. Combining MTBUR/MTBF data, delay codes, and AOG logs helps identify where the real ground-time risk is emerging in your specific operation. This requires data quality and consistent failure coding, which are often weak points in brownfield environments, and those weaknesses should be acknowledged when presenting the risk map. The result is a prioritized set of components that reflects both design intent and operational reality.
In most organizations, the data needed to perform this prioritization lives across legacy MRO, ERP, engineering, reliability, and document management systems that do not integrate cleanly. Full replacement of these systems just to improve AOG risk mapping is rarely viable due to validation cost, operational downtime risk, and the long lifecycle of existing assets and certifications. Instead, most teams succeed with incremental approaches: targeted data extracts, reconciled part and configuration lists, and manual review by engineering and maintenance experts. Any AOG risk map built in such an environment should explicitly document its data sources, known gaps, and manual assumptions so leaders do not mistake it for a fully authoritative view. Over time, those same mappings can inform where to invest in better integration or master data cleanup.
The components you prioritize in the AOG risk map should directly inform stocking policies, repair loop management, and contingency plans, but none of these interventions are automatic. Regulatory constraints, capital limits, and warehouse capacity mean you cannot simply buy your way out of AOG risk for every high-priority item. For some components, the best mitigation may be alternative repair schemes, pooled inventory with partners, or pre-negotiated access to third-party stock, all of which introduce their own governance and traceability burdens. For others, design or reliability improvements may be more cost-effective than deeper stocking, but carry certification and validation overhead that must be weighed realistically. Treat the AOG risk map as a decision-support tool that highlights tradeoffs, not as a guarantee that specific actions will prevent future groundings.
Whether you're managing 1 site or 100, Connect 981 adapts to your environment and scales with your needs—without the complexity of traditional systems.
Whether you're managing 1 site or 100, C-981 adapts to your environment and scales with your needs—without the complexity of traditional systems.
