SCOR Best Practice 168: Rotable Spares Pool

For companies relying on equipment to keep operations running—whether in mining, aviation, manufacturing, or healthcare—downtime is costly. One powerful way to reduce that risk is by managing a Rotable Spares Pool—a strategy that ensures broken parts can be swapped out quickly with serviceable replacements.

But managing a rotable pool effectively requires careful planning. The SCOR (Supply Chain Operations Reference) model offers best practices for how to set up and optimize these pools, ensuring spare parts are always available without tying up too much capital.

This blog breaks down what rotable spares are, how to manage them effectively, and real-world examples of companies doing it right. For us though, it is an interesting example of how we can take a well established concept in one area, and use it as inspiration for others. So where we have expensive assets, it makes sense to repair them as the most cost effective option. This in many ways is a circular economy where we re-use, we bring return flows, we manage forwards and backward movement, we avoid raw extraction of materials and new production. This is well established in MRO supply chains, but it is also a challenge many companies face when trying to think of new ways to be sustainable.

What is a Rotable Spares Pool?

A rotable spare is a part that can be repaired and reused multiple times. Instead of waiting for a broken part to be fixed, companies keep a pool of ready-to-use replacements. Once a faulty part is removed, it’s repaired and returned to the pool for future use.

For example:

• In aviation, landing gear, avionics, and engines are managed as rotable spares.
• In healthcare, MRI scanner components are swapped out while repairs are done off-site.
• In mining, hydraulic pumps and motors are rotated to keep machinery running.

The goal is simple: minimize downtime while keeping inventory and costs under control.

SCOR Best Practices for Managing Rotable Spares

The SCOR model outlines key processes and practices for managing rotable spares effectively. Here’s how it breaks down:

1. Standardize the Process (S4 & R3 – Return and Repair):
   • When a part fails, the return process should be quick and seamless.
   • SCOR suggests using a clear Return Merchandise Authorization (RMA) process to track faulty parts.
   • Best Practice: Use barcode scanning or IoT sensors to trigger returns automatically when a part fails.
2. Optimize Maintenance and Repair (T3 – MRO Management):
   • Once a faulty part is returned, it should go through a standard repair process to ensure consistent quality.
   • Best Practice: Implement a Condition-Based Maintenance (CBM) system. For example, GE Aviation uses predictive analytics to identify when aircraft parts are likely to fail and swap them out before breakdown.
3. Manage Inventory Efficiently (HS.0058 – Inventory Management):
   • The challenge is maintaining enough spares without overstocking.
   • Best Practice: Use dynamic safety stock calculations based on lead times, usage rates, and part criticality.
   • Example: Rolls-Royce’s TotalCare program uses real-time monitoring to manage engine rotable pools efficiently, ensuring they have the right parts available without excess.
4. Prevent Obsolescence (HS.0205 – Supply Market Research):
   • As equipment evolves, older parts can become obsolete, leading to wasted inventory.
   • Best Practice: Regularly review your spare parts catalog and collaborate with suppliers to ensure parts are still relevant.
5. Track Performance (RL.2.2 – Delivery Performance to Commit Date):
   • Measure how quickly you can replace a broken part and return the repaired one to the pool.
   • Example: Siemens Mobility uses digital twins to simulate spare parts demand and optimize their rotable pools for railway systems.

Real-World Examples of Rotable Spare Management

Here are some real-world examples of companies improving their rotable spares processes:

1. Aviation: Delta Airlines
   Delta reduced aircraft turnaround time by implementing an advanced rotable spares program. By using predictive maintenance and automated tracking, they achieved a 20% reduction in spare part inventory while improving aircraft availability.
   👉 Read more here. https://www.descartes.com/resources/knowledge-center/customer-success-story-delta-rfid-air-cargo?utm_source=chatgpt.com
2. Mining: The key metric to be managed in mining is the reduction of downtime. Effective management of rotables helps ensure stock of critical parts are available when needed.

How to Improve Your Rotable Spares Pool: 5 Practical Tips

1. Classify Parts by Criticality: Focus on high-impact, long-lead-time items first.
2. Implement Predictive Maintenance: Use sensors and historical data to forecast failures.
3. Automate Tracking: Barcoding or RFID can streamline returns and repairs.
4. Right-Size Inventory: Balance availability with cost using dynamic safety stock calculations.
5. Review Regularly: Conduct periodic reviews to avoid obsolescence and optimize pool size.

Conclusion

Those who work in industries that rely heaving on critical assets, then these rotable concepts are nothing new. For those who do not, it is an interesting key concept to be aware of. When the cost of buying new parts may be prohibitive, we can see here how the Supply Chain process must manage a backwards and forwards flow. In many ways, this is the circular economy. Can we bring a bit more of a rotables concept with us in other areas? If we did, it may flag up new and novel ideas on how to create new circular economies & new supply chains.