Skip to main content
News
February 24, 2026

Critical parts strategies to mitigate and manage AOGs

Viktor Bulanov, Head of Sales and Customer Support at FL Technics, a leading global provider of MRO services, shares an in-depth analysis of what causes AOGs, and how airlines and MROs can deploy smart strategies to both manage and prevent these costly events.

From component failures to supply chain issues to parts in incorrect locations, Aircraft on ground (AOG) incidents have a range of potential causes. When they do occur, it is critical to have a rapid response capacity in order to minimize the disruption and financial costs. Importantly, airlines and MROs can take proactive steps to stop AOGs from occurring in the first place. This can be done by leveraging demand forecasting, ensuring close collaboration between MROs, OEMs and airlines, and having effective remote warehousing, flight kit usage, and remote station preparedness.

AOGs are an operational and financial hit

AOG incidents present airlines with a range of complex and costly problems. In terms of operations, AOGs result in flight cancellations, passenger rebooking, and cargo rerouting. “These issues occur simultaneously, creating a complicated mix of inter-connected disruptions,” comments Viktor Bulanov. “There is a knock-on effect on crew duty times, network connectivity, and maintenance scheduling.” In this fast-moving and chaotic context, airlines must make rapid decisions. “They need to make adjustments to the network schedule and deploy replacement aircraft,” adds Bulanov.

“Airlines also take a financial hit across multiple cost streams during an AOG,” Bulanov continues. “There is the direct loss of revenue from having an aircraft grounded. Added to this is passenger compensation, plus costly logistics and last-minute parts sourcing.”

The causes of AOGs

Three main issues most commonly lead to AOG incidents, according to Bulanov. “First of all, there are component failures, where component fails due to wear or as the result of unexpected events, that components must immediately be replaced before the aircraft can fly again.”

“Secondly, there are supply chain issues. Supply shortages can result from long lead times at Original Equipment Manufacturers (OEMs) or shop backlogs. These have knock-on effects, delaying repair times and leading to maintenance windows being exceeded. Finally, there are sometimes mismatches between the locations where parts are needed and where they are stored.”

The good news is that mitigating these problems, or even proactively preventing them, is possible. The FL Technics team employs a range of practices and strategies to help prevent AOGs or limit their disruptiveness.

A global network and rapid response capability

In complex or time-sensitive scenarios such as AOGs, having extensive reach and a well-developed network is important. FL Technics operates strategically positioned inventories in 4 regions: Europe, the Americas, the Middle East, and the Asia-Pacific region. “We maintain both complete components and critical expendables and consumables parts for the 737, A320, and Embraer families,” says Bulanov. “In total, we have over 100 line maintenance stations. This wide geographical spread is complemented by our urgent shipping solutions and 24/7 support. As a result, we can immediately dispatch parts or find alternative sourcing solutions in order to minimize the operational disruption and financial impact of AOGs.”

Proactive prevention through demand forecasting

Rapid response is clearly important. However, being able to proactively prevent AOGs through demand forecasting is a more effective way to reduce costs and minimize disruption. “Demand forecasting is when you analyze usage patterns, reliability data, and maintenance schedules to identify potential failures in advance,” explains Bulanov. “You can then ensure that i components with high failure rates are available in strategic locations so operations can be maintained.”

“At FL Technics, we analyze performance data, tracking failure patterns across our global customer base,” Bulanov continues. “This enables us to pre-position critical components where they are most likely to be needed. We can also better manage our A320, 737, and Embraer parts inventories. The result is an optimized supply chain where appropriate stock levels are maintained in critical areas.” By augmenting this demand forecasting with pooling arrangements and exchange programs, FL Technics is able to reduce AOG risk for its customers.

Close collaboration between MROs, OEMs and airlines

According to Bulanov, there are multiple ways MROs, OEMs and airlines can collaborate in order to reduce the likelihood and impact of AOGs. “In terms of proactive preparations, these parties can exchange maintenance forecasts, inventory data, and usage patterns,” he comments. “Sharing specialized tools and test equipment can also help because it maximizes the use of these resources while minimizing the investment requirements of individual players.”

FL Technics often takes on a principal role in enabling such collaboration, thanks to its broad network and well-developed industry relationships. “Our digital collaboration tools support our network in working together. Our platform connects more than 1,000 suppliers and processes over 50,000 parts requests per month. Furthermore, we have exchange programs in place that have been proven to cut AOG response times. By facilitating flexible sharing and joint planning initiatives, we enable our stakeholders to reduce capital investments while maintaining operational readiness,” Bulanov says.

Balancing remote warehousing and flight kit usage

One common form of AOG preparation used by airlines is flight kits, where critical lightweight components are carried onboard and are then readily available if a part needs repairing or replacing. “Flight kits function like insurance,” explains Bulanov. “And just like any insurance policy, you need to find the right balance between being covered and overpaying for unnecessary protection. Every component carried adds fuel burn costs, plus they require regular updating. So, the aim should be to only carry items that justify their weight and inventory costs.”

The alternative to flight kits is remote warehousing, where components and parts are stored in warehouses in strategic locations. “Through strong regional support, we are able to make a large number of critical parts readily available to our clients,” Bulanov explains. “In our experience, having a small number of critical and lightweight items onboard, such as sensors and avionics cards, and utilizing remote warehousing for the remainder, is optimal,” Bulanov concludes.

Remote station preparedness

“Having accessible regional stock certainly becomes more challenging for remote locations,” continues Bulanov. “There are economic constraints to comprehensive inventory positioning, and strict quality requirements limit qualified supplier options at remote stations.” The complex logistics requirements and limited support options in these locations can result in procurement expenses doubling.

However, there are steps airlines can take, with the support of experienced MROs, to manage this challenge. “Airlines should identify their critical network points, then validate local support capabilities for these locations. Developing emergency contingency plans is also important, including testing customs processes, double-checking handler capabilities, and exploring multiple transport options.”

“FL Technics is on-hand to support airlines. We maintain ready-response arrangements with customs authorities and handlers. Plus, we have a 24/7 AOG desk available to coordinate response options. With alternative routing plans and backup transport modes in place for each major route, and a network of local partnerships, we can consistently deliver parts to remote stations within critical response windows.”