British Airways requires all of their pilots to retire at age 55, even though the maximum age in the EU is 65. Their pension and retirement benefits are designed around that assumption.

In a different vein, GE requires all their upper level management, including the President and CEO to retire at 65, no hanging on until 70+ as some companies allow.

Looks to me like a company can have maximum retirement ages that are below federal mandated maximums if they choose. IOW, FedEx could possibly create company requirement that all their pilots retire at age 60 if the company chose.