Sounds like it is included as part of standardized airplane checks based on age of aircraft + hours flown.

[1]: https://en.wikipedia.org/wiki/Aircraft_maintenance_checks#AB...

On things like D check, the aircraft is essentially completely taken apart and inspected at that level typically taking 50,000 man hours and 6 month-1 year of time.

Thanks for this post. I’m blown away by that 50,000 hours figure.

The article mentions the cost and that Boeing underestimates it. When you divide the cost by the number of hours, it seems very reasonable. Parts and materials being included. I’m surprised any job that extensive isn’t even more expensive.