The resilience of the supply chain really comes from our ability to hold sufficient spares and to have the repair and overhaul capacity that's required when it's needed. Our time frames, looking out 30, 60 and 90 days and beyond, are sufficient to maintain our supply chains and we haven't had any specific issues through the past eight months of the COVID pandemic.
When we look at our supply chain resilience in the longer term, there's a balance to be found between the cost of warehousing sufficient spares for different operational circumstances and tempos and having second sources of supply, for example, or more assured sources of supply—either domestically or with allies.
Through the pandemic response, our ability to reach out internationally to our allies and work co-operatively with them has been key to keeping those supplies moving. I'm happy to report that we haven't run into any issues.