Last-Minute Flight Schedule Changes Wear Out Pilots, Unions Say

Sudden changes to flight schedules are driving up fatigue reports and damaging morale for pilots at the nation’s largest airlines, say aviator unions, which plan to make the issue a top priority in new contract talks next year.

Pilots at American Airlines Group Inc. had about a 33 percent chance of being switched to a new or longer flight schedule during the summer’s peak travel season, the highest rate ever, according to Allied Pilots Association calculations based on company data. Aviators at Delta Air Lines Inc. say their rate is about the same, although the carrier disputed that.

The ability ...