Amid the shutdown, the FAA will take the extraordinary step of reducing air traffic by 10% across 40 high-volume markets starting Friday, citing controller fatigue and staffing strains as unpaid crews work long hours. Administrator Bryan Bedford said the move is temporary and preventative, with affected airports to be named Thursday after talks with airlines. United, Southwest and American vowed to minimize disruption; United will target regional and nonhub routes and offer refunds. Cirium estimates up to 1,800 flights and 268,000 seats could be cut. Weekend staffing alerts have spiked, and industry groups urge Congress to end the shutdown.

Prepared by Christopher Adams and reviewed by editorial team.