WASHINGTON >> Air-traffic controllers cleared an Alaska Airlines jet last month to take off at Tennessee’s Nashville International Airport on the same runway where a Southwest Airlines plane had been cleared to cross, the National Transportation Safety Board said today.

The Sept. 12 incident prompted Alaska Airlines Flight 369 , a Boeing 737 MAX 9 airplane with 176 people on board, to abort takeoff to prevent a collision. The Alaska pilots quickly applied the brakes, blowing the plane’s tires.

The NTSB said a ground controller cleared the Southwest plane to cross Runway 13 just after 9:13 a.m. and 23 seconds later another controller cleared the Alaska plane to depart.

The Federal Aviation Administration referred questions to the NTSB, which is leading the investigation. The FAA has a separate investigation into the incident, where Southwest Airlines Flight 2029 – a Boeing 737-700 with 141 people onboard – was scheduled to depart for Jacksonville, Florida.

Over the last two years, a series of near-miss incidents have raised concerns about U.S. aviation safety and the strain on understaffed air-traffic-control operations. FAA Administrator Mike Whitaker said last month the number of serious runway-incursion incidents had fallen by over 50%.

Tracking website Flightradar24 said the Alaska plane was traveling at 104 knots (120 mph, 193 km per hour) on the runway before slowing.

The FAA said in April it would install new surface-awareness technology at four airports including Nashville’s by July. The FAA previously declined to comment on whether the technology was operating.

In June, the NTSB found that incorrect assumptions by an air traffic controller led to a February 2023 near-collision between a FedEx plane and a Southwest aircraft in Austin, Texas.

The two planes came within about 170 feet (52 meters) of each other when the FedEx Boeing 767 was forced to fly over the Southwest 737-700 to avoid a crash in poor visibility.