For travelers, the practical impact is concentrated on Saturday departures and arrivals between late morning and midnight. Passengers booked on flights during those hours should expect rebooking onto earlier Sunday slots or alternative airports. The TSA advised arriving at least three hours early on Friday and Sunday, when volume will spike as travelers compress their schedules around the closure.

The shutdown is the most extensive airspace restriction at Reagan National since the 2009 presidential inauguration, when the airport closed for roughly 12 hours. The 15-hour window reflects the scale of the July 5 programming, which includes a parade down Constitution Avenue, a concert on the Mall, and a fireworks display expected to draw more than 500,000 spectators.

Airlines have been here before. The 2019 Fourth of July celebration on the National Mall triggered a 12-hour DCA closure, and carriers adjusted schedules with roughly two weeks of lead time. This year's notice came about three weeks out, giving airlines more time to reallocate aircraft and crews.

The FAA said it coordinated the timing with the White House, the Secret Service, and the National Park Service to minimize disruption while ensuring security for the event. The agency expects normal operations to resume by 12:01 a.m. Sunday.

For passengers already holding tickets, the advice from carriers is consistent: check flight status before heading to the airport. Most airlines have waived change fees for flights into or out of DCA on July 5, allowing rebooking through July 8 without penalty.

The closure is a reminder that even routine air travel bends to the demands of a once-in-a-generation national celebration. The 250th birthday is a single weekend. The schedule changes that come with it will ripple through the system for days.