I fly a King Air 200 single pilot on corporate flights–I have over 11,000 hours in King Airs, and fly them between 350 and 600 hours a year. I normally fly single-pilot–but do have the option of having a copilot if the trip will be difficult (weather, duty time, busy airspace, or “if I just feel like it.”) I often take a younger pilot along just to give them the experience on turbine aircraft.–and often take my Private Pilot wife along. I’m typed in 6 jets, but don’t have one to fly today. People ask about flying the King Air single pilot–I respond “It’s under 12,500#–what’s the difference between flying it or a Baron–are you proposing to ground anyone over 65?” The King Air is easy to fly and well equipped–and nearly every flight is IFR–but little “in the weather” time in the flight levels. I’m in good health–take my flight physicals at Mayo Clinic–and take an insurance-mandated training and check ride every year.
If people are worried about pilot incapacitation–perhaps they would be more comfortable if the age were LOWERED to the 30’s-- (witness the Caravan pilot incapacitation). All in all, pilot incapacitation is something to CONSIDER–but age alone is not an issue. I’ve seen studies that show NO CORRELATION between accidents for older pilots (with the exception of gear-up landings) and the general pilot population. Most older pilots don’t HAVE to fly due to schedules–they (like ALL pilots) have the option to refuse a flight. Also, many older pilots are retired professionals–who have no problem refusing a flight.