Flight delays may be the norm at San Francisco International Airport (SFO) this summer.
The Federal Aviation Administration has slashed arrivals by a third to 36 flights per hour due to construction work on SFO’s north-south runways and safety concerns over parallel flight approaches, the regulator told TPG. The cap will rise to 45 flights per hour in October after the runways reopen, but that is still below the 54 flights per hour that were previously allowed.
Travelers should expect that a quarter of all flights to SFO this summer will experience a delay of 30 minutes or longer, an airport spokesperson said.
Both the FAA and the airport are working to increase the arrival rate, they said separately.
The SFO flight reductions are the latest by the FAA to mitigate potential delays and improve safety at major airports. In March, the agency moved to reduce flights at Chicago's O’Hare International Airport (ORD), where American Airlines and United Airlines are in a fierce battle for gate space, to just 2,608 flights a day, down from the 3,080 flights scheduled on peak days this summer. No decision has been made on how the ORD reductions will occur.
And in 2025, the FAA limited movements — a takeoff or landing is one movement — at Newark Liberty International Airport (EWR) to 72 an hour through this October.
The safety-related flight reductions at SFO come just over a week after an Air Canada regional jet crashed into an airport fire truck at New York’s LaGuardia Airport (LGA), killing both pilots.
While the FAA has been quick to limit capacity at airports around the U.S., the agency has said little on how it plans to increase capacity amid rising demand for air travel. The Trump administration is investing billions of dollars in upgrading the nation's air traffic control system but has not said how much those investments will increase air traffic capacity.
The issue at SFO is the distance between its runways. Both the two east-west runways and the two north-south runways are just 750 feet apart, among the closest in the country, FAA data shows. The agency requires special rules for simultaneous approaches to parallel runways less than 2,500 feet apart.
Previously, flights were allowed to approach SFO’s two east-west runways in a staggered formation, with one plane just ahead of the other. That allowed the airport to handle up to 54 arrivals an hour in good weather.
Arrival rates are already significantly reduced in bad weather, which is common at fog-prone SFO.
Brett Snyder, founder of Cranky Concierge and author of the "Cranky Flier" blog, wrote Thursday that there is a silver lining to the FAA’s flight cap at SFO.
“The airport is likely now going to be much better operationally,” he wrote. “If capacity is the same in good or bad weather, the airlines will create a schedule that works no matter what.”
Still, a reduction in arrival capacity has implications for airlines. SFO is a major hub for United and a key base for Alaska Airlines.
United is “reviewing the FAA’s updated guidance to determine if we will need to make any changes to our flight schedule in the future,” a spokesperson said.
Alaska Airlines is “closely monitoring the situation at SFO and the dynamic is changing by the day,” a spokesperson said.
More than a quarter of all arrivals at SFO (or 154 flights) were delayed on Wednesday, according to data from flight-tracking website FlightAware.
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