U.S. airlines canceled hundreds of flights on Friday after the FAA ordered reductions due to air traffic controllers missing paychecks amid the historic government shutdown.

Staffing shortages affected major airports, including Newark, San Francisco, and Atlanta, causing widespread delays and forcing airlines to adjust schedules at the last minute.

More than 700 flights were canceled as of 9 a.m. ET, about 3% of the day’s schedule, with cancellations expected to rise to 10% by Nov. 14.

Analysts noted that while fewer seats could temporarily boost revenue, prolonged disruptions may reduce near-term booking demand, CNBC has reported.

The cancellations also drove a surge in alternative travel, with Hertz reporting a more than 20% increase in one-way rental reservations compared with last year.