My understanding is the 56 year old age limit is due to burnout and other accumulated negative risk factors from the profession. You have a shelf life like a professional athlete due to the sustained high cognitive load and stress of the workload. Replies open to additional references and citations.

It would make an interesting reality TV show to have a group of 60-70 year olds attempt to perform a simulated 8 hour ATC shift under "live fire" conditions.

https://web.archive.org/web/20260323212332/https://www.crisi...

https://www.faa.gov/newsroom/media/Fatigue_Report.pdf

https://news.siu.edu/2025/07/072225-siu-research-focuses-on-...