ATC Error Leads To Southwest 737 Close Call On San Diego Runway

This isn’t good… air traffic controllers cleared two Southwest jets to use the same runway at the same time. This caused a close call, including a high speed rejected takeoff.

Southwest 737 incident at San Diego Airport

This incident happened on Friday, October 11, 2024, at San Diego International Airport (SAN). It involves the following two flights:

• Southwest 1478 was getting ready to depart for Dallas (DAL), and was operated by a seven-year-old Boeing 737-800 with the registration code N8551Q
• Southwest 785 was getting ready to depart for Phoenix (PHX), and was operated by an 18-year-old Boeing 737-700 with the registration code N262WN

This situation happened due to a lapse in communication between the ground controller and tower controller at the airport. VASAviation has an excellent video with both the air traffic control audio and a depiction of where the jets were located during the incident.

Here’s the key part of the communication, and keep in mind that tower and ground controllers are on different frequencies (though the transmissions are in chronological order):

San Diego Tower: “Southwest 1478, Lindberg Tower, runway 27, line up and wait.”
Southwest 1478: “Runway 27, line up and wait, Southwest 1478.”
San Diego Ground: “Southwest 785, cross runway 27 at B6, continue taxiing via C.”
Southwest 785: “Alright, cleared to cross 27 at B6, continue taxiing via C, Southwest 785.”
San Diego Tower: “Southwest 1478, traffic on the upwind is diverging course, runway 27, cleared for takeoff.”
Southwest 1478: “Runway 27, cleared for takeoff, Southwest 1478.”

The issue here is that the tower controller gave a plane clearance for takeoff literally one second after another plane had been given clearance to cross that same runway.

Once the controller figures out what’s going on, here’s how the communication goes:

San Diego Tower: “Southwest 1478, cancel takeoff clearance.”
San Diego Ground: “Southwest 785, hold position.”
Southwest 785: “Hold position, Southwest 785, we’re past the hold short line.”
San Diego Ground: “Roger, just hold position please.”
San Diego Tower: “Southwest 1478, did you copy?”
Southwest 1478: “Say again.”
San Diego Tower: “Cancel takeoff clearance for Southwest 1478.”
Southwest 1478: “Southwest 1478 rejecting.”

The Southwest 737 trying to take off had accelerated to around 100 knots, prior to rejecting its takeoff. It ended up exiting the runway at the same intersection where the other 737 was trying to cross.

Southwest 785 ended up departing a short while later, while Southwest 1478 had to return to the gate, and then departed around three hours behind schedule (since a high speed rejected takeoff can require an aircraft inspection, etc.).

This situation was a complete mess

It’s sad how common runway incursions have become in the United States, especially since these situations seem so avoidable. A couple of things stand out about this incident.

First of all, it just seems like common sense that the tower controller should be responsible for all movements across a runway, even if it’s an aircraft taxiing. It makes no sense that two different parties on two different frequencies are giving instructions for use of the same runway. In many other countries, that’s how it works, and it should work that way in the United States as well, in my opinion.

Second of all, the way that the tower controller dealt with the situation leaves a lot to be desired. She nonchalantly told the Southwest jet to “cancel takeoff clearance,” but the pilots clearly didn’t hear those instructions. She waited for several seconds, and then in response to that, the pilots of the jet taking off said “say again?” Her lack of urgency in how she communicated, plus not emphasizing the gravity of the situation, really isn’t great.

It’s also interesting (but not surprising) how the controllers try to completely sweep this situation under the rug. There’s no real apology to the pilots, but they just move on. I understand you want to save the frequency for important communication, but at least acknowledging what happened seems like it would’ve been appropriate.

On the plus side, given Southwest’s recent issues, at least it wasn’t the carrier’s pilots at fault, for once?

Bottom line

Two Southwest Boeing 737s had a close call in San Diego, as the planes were cleared to use the same runway at the same time. The ground controller cleared one aircraft to cross the runway at the same time that a tower controller cleared another aircraft to depart from the same runway.

The problem here isn’t just the initial problem, but how the situation was handled, as the pilots of the plane taking off seemingly didn’t even initially know that their clearance had been canceled.

What do you make of this Southwest 737 runway situation?