The San Diego International Airport has seen an increase in delays in recent months and while the reasons for those delays may vary, there are few clues as to why SAN is frequently impacted. The Federal Aviation Administration and an aviation expert share with NBC San Diego some of the top reaso ns flights are impacted in San Diego. Volume delays One reason for some late takeoffs and landings is what the Federal Aviation Administration calls a “volume delay.” The FAA says that happens when the number of aircraft trying to use an airport or airspace exceeds the system’s capacity at that moment. “Yeah, I saw the statistics of the flight that we were going to take were 65% arrival on time. So that’s not super, you know,” said one traveler at SAN on Monday. “Like flying out of Kansas City, we had like the two hour delay that summer was off the plane. Then when we were coming back home, it was the weather.” Runway limitations Annmarie Heth, who teaches aviation and aerospace science at MSU Denver and previously worked in airport operations, said several factors can contribute to delays. Heth said San Diego International Airport is unique because it is the busiest single-runway airport in the country. “You can build more gates, expand terminals, improve the passenger experience, but that doesn’t create runway capacity for you.” Impacts from other airports Heth said delays can also be connected to what is happening elsewhere in the country. Department of Transportation statistics show on-time departures have declined from 84% in 2021 to 72% as of now. On-time arrivals have dropped from 82% to 71%. Another factor is the way airlines schedule flights, a practice known as banking flights. “So during the summer, maybe a popular destination in the Caribbean or in Mexico is where folks are heading for a summer vacation. So all the airlines are going to be wanting that kind of same flight, that same route right around the same time to compete with each other.” Weather The biggest reason for delays is maybe the most obvious. The FAA said weather is the number one cause of delays and cancellations. Renovations The FAA also said it is in the middle of a $12.5 billion air traffic control overhaul that has been slowing traffic at airports. The overhaul is intended to optimize airspace and decrease delays once completed. It includes electronic flight strips, digital displays and radar to better track what is happening on the ground, as well as a singular system designed to bring together information on weather, flight paths, traffic flow and staffing. Heth said pinpointing a single cause of a delay can be difficult because multiple agencies and systems are working together at any given time. “So something that might not be happening at San Diego at all, is going to affect flights in and out of San Diego.” For travelers, that can mean planning for potential delays as the FAA works to address issues affecting air traffic and airports. This story was originally reported for broadcast by NBC San Diego. AI tools helped convert the story to a digital article, and an NBC San Diego journalist edited the article for publication. ...read more read less