The NTSB and FAA are investigating a close call between a FedEx 767 and Southwest Airlines 737 in Austin. The NTSB issued a statement saying it is “investigating a surface event at Austin-Bergstrom International Airport Saturday, a possible runway incursion and overflight involving airplanes from Southwest Airlines and FedEx.”
Landing and departing Runway 18L
At the time of the incident FedEx 1432 arriving from Memphis was cleared to land on Austin’s Runway 18L and the controller then cleared Southwest 708 to depart when the FedEx 767 was approximately 3 miles from the runway. The Southwest 737 was still on the runway at 12:40 UTC (6:40 am local time) as the FedEx flight reached the runway, so the FedEx pilots initiated a go-around. The Southwest flight continued its departure and arrived safely in Cancun 1 hour 54 minutes later. The FedEx flight circled the airfield and landed safely 12 minutes after the incident.
Interpreting the ADS-B data
We have downloaded and processed the granular ADS-B data. In this discussion we are referencing data from a single receiver Flightradar24 ADS-B receiver located near the airport that received data from both aircraft. This helps us ensure timing consistency between data points.
The Southwest flight SWA708 entered the runway at 12:39:37.996. At this time, the FedEx flight FDX1432 was 2.35 miles from the runway threshold. SWA708 began its departure roll at 12:40:15.075 when the FedEx aircraft was approximately .676 miles from the runway threshold.
At its lowest point, FDX1432 sent an altitude value of 75ft. It is important to note a limitation related to ADS-B altitude values in situations close to the ground. The altitude reported by ADS-B data is a barometric value above mean sea level (AMSL) calibrated at standard atmospheric pressure. It is not the height of the aircraft above the ground. The aircraft’s radio altimeter would be providing the pilots with the aircraft’s height above the ground at this stage of flight.
At the closest point horizontally, the aircraft were less than 1000 feet apart, but we do not have same-time data points in order to calculate an exact figure. It is also important to note that the position broadcast via ADS-B is from a specific point on the aircraft and parts of the aircraft may be closer or further to the other aircraft than the place from which the GPS position is derived.
Download Flightradar24 Data
Included below are two sets of files for each aircraft. We have included the full flight standard frequency CSV and the granular frequency, singular receiver data for both flights.
Weather conditions
KAUS 041253Z 00000KT 1/8SM R36R/1800V2400FT FZFG VV002 M01/M01 A3043 RMK AO2 SLP309 T10061006
KAUS 041218Z 00000KT 1/4SM R36R/1800V2400FT FZFG VV002 M01/M01 A3043 RMK AO2 T10061006
Visibility at the time of the incident was marginal and decreasing. Frozen fog was reported in the 12:18 UTC and 12:53 UTC METARs with visibility decreasing from 1/4 mile (.4 km) to 1/8 mile (.2 km) between reports. The incident occurred approximately 13 minutes prior to the second METAR reading.
Aircraft information
The Southwest flight was operated by a Boeing 737-700 registered N7827A, acquired by Southwest Airlines in 2015. It is powered by two CFM56-7B engines.
The FedEx aircraft is a 767-300F registered N297FE, acquired by FedEx in 2015. It is powered by two CF6-80 engines.
30 November 2023 — NTSB updates docket
The NTSB released its full docket for the investigation on 30 November, including flight data, interview transcripts, and another factual information. A final report and finding of probable cause is still forthcoming.
6 June 2024 — NTSB releases final report
The NTSB has released its final report on the incident, finding a “lack of critical safety technology and incorrect assumptions by an air traffic controller led to a near-collision” between the Southwest 737 and FedEx 767.
