Key provisions of the Act include the following:
• As of 12/13/07, part 121, § 121.383(c), specifying age 60, ceases to be effective.
• A pilot age 60+ acting as pilot in command (PIC) in international operations must be paired with a pilot under age 60 (consistent with the current ICAO requirement).
• In domestic operations both pilots may be age 60+.
• It permits the continued employment of a pilot who reaches age 60 on or after 12/13/07.
• It permits the employment as a new-hire a pilot who reached age 60 before 12/13/07.
• A pilot age 60+ will not be subjected to different, greater, or more frequent medical exams.
• Any pilot age 60+ must hold a first-class medical certificate, renewable on a 6-month cycle.
• Any air carrier employing pilots age 60+ must adjust its training program to ensure such pilots’ skill and judgment continue at acceptable levels.
• Any pilot age 60+ must undergo a line check at 6-month intervals.
• For a pilot age 60+ acting as second in command (SIC), a regularly scheduled simulator evaluation may substitute for a required line check.
Over 60 pilots get more checkrides and may be slower on the uptake. Those FOs senior enough will bid away from them. Over time, the over sixty guys are flying with more and more junior pilots. Makes sense that between the age and more junior FOs they fly with, having a check airman on board may be more problematic than typical.
I can tell you at one carrier, some of these over 60 were getting line checks every 4 to 5 months. They carrier didn't want to miss the six month check due to scheduling issues, so they have an "early month" that sometimes even went a month earlier than that. The "six month" requirement was interpreted as you can't go six months without a check. It established a "drop dead" date. So if you get a check at the 5-month point, you have to get another one 6 months later or, if in the "early month," just five months later. That's two in 10 months. If you get an occasional even earlier, you could have two in 8 months, maybe three in 12 months.
Over age-60 busts could just be a matter of the increased number checkrides rather than them them doing worse than under 60 pilots. For example, if out of every 100 checkrides there is a bust, a group of over 60 pilots will reach 100 checkrides sooner than a group of under 60 pilots because they're taking checkrides at double the rate. They may be failing more, but it is because they are exposed to an eval at twice the rate.