BOEING 737-79PSOUTHWEST AIRLINES CO
Austin, TX, USA · 2023-02-04·N7827A
What happened
NTSB summary, verbatimOn February 4, 2023, about 0640 central standard time, Southwest Airlines (SWA) flight 708, a Boeing 737-700, N7827A, and Federal Express Corporation (FedEx) flight 1432, a Boeing 767-300, N297FE, were involved in a runway incursion at Austin Bergstrom International Airport (AUS), Austin, Texas. The flight crew of the FedEx airplane, which was arriving on runway 18L, executed a missed approach as the SWA airplane was departing from the same runway. The 128 occupants aboard the SWA airplane and the 3 occupants aboard the FedEx airplane were not injured, and neither airplane sustained damage. SWA flight 708 was a regularly scheduled international passenger flight operating under Title 14 Code of Federal Regulations (CFR) Part 121 from AUS to Cancún International Airport (CUN), Cancún, Mexico. FedEx flight 1432 was a domestic cargo flight operating under Part 121 from Memphis International Airport (MEM), Memphis, Tennessee, to AUS. Night instrument meteorological conditions prevailed at the time of the incident.
Photographs
1the aircraft, and what the investigators foundProbable cause
the Board's determinationthe local controller’s incorrect assumption that the Southwest Airlines (SWA) airplane would depart from the runway before the Federal Express airplane arrived on the same runway, which resulted in a loss of separation between both airplanes. Contributing to the controller’s incorrect assumption were his expectation bias regarding the SWA airplane’s departure, his lack of situational awareness regarding the SWA airplane’s position when the flight crew requested takeoff clearance, and the air traffic control tower’s lack of training (before the incident) on low visibility operations. Contributing to the incident was the SWA flight crewmembers’ failure to account for the traffic that was on short final approach and to notify the controller that they would need additional time on the runway before the takeoff roll. Also contributing to the incident was the Federal Aviation Administration’s failure to require surface detection equipment at Austin-Bergstrom International Airport and direct alerting for flight crews.
Occurrence sequence
2 stepsNTSB coding · CICTT taxonomy- 1 · TakeoffRunway incursion veh/AC/persondefining event
- 1 · Approach-IFR missed approachNear midair/TCAS alert/loss of separationdefining event
Findings
12 causal · 1 contributing- CAUSEPersonnel issues › Action/decision › Info processing/decision › Expectation/assumption — ATC personnel
- CAUSEPersonnel issues › Action/decision › Info processing/decision › Expectation/assumption — ATC personnel
- CAUSEPersonnel issues › Psychological › Attention/monitoring › Task monitoring/vigilance — ATC personnel
- CAUSEPersonnel issues › Psychological › Attention/monitoring › Monitoring other aircraft — ATC personnel
- CAUSEOrganizational issues › Support/oversight/monitoring › Training › Recurrent training — ATC
- CAUSEOrganizational issues › Support/oversight/monitoring › Training › Recurrent training — ATC
- CAUSEPersonnel issues › Psychological › Attention/monitoring › Monitoring environment — Pilot of other aircraft
- CAUSEPersonnel issues › Task performance › Communication (personnel) › Lack of communication — Pilot of other aircraft
- CAUSEPersonnel issues › Task performance › Communication (personnel) › Lack of communication — Flight crew
- CAUSEOrganizational issues › Support/oversight/monitoring › Enforcement › Equipment requirements — FAA/Regulator
- CAUSEOrganizational issues › Support/oversight/monitoring › Enforcement › Equipment requirements — FAA/Regulator
- CAUSEPersonnel issues › Psychological › Attention/monitoring › Monitoring environment — Flight crew
- FACTORAircraft › Aircraft systems › Indicating/recording systems › Data recorders (flight/maint) — Design
Safety recommendations
7 issuedwhat changed because of this accidentTO THE FEDERAL AVIATION ADMINISTRATION: For airports that are certificated under Title 14 Code of Federal Regulations Part 139 and are currently not equipped with airport surface detection equipment, model X (ASDE-X) or airport surface surveillance capability, implement surface detection equipment that • tracks the movement of arriving and departing aircraft, • determines the proximity between those aircraft, and • provides air traffic controllers with visual and aural cues of surface movements to aid in their decision making processes.
TO THE FEDERAL AVIATION ADMINISTRATION: Require air traffic controllers to • advise pilots, through direct communication and automatic terminal information system broadcasts, when visual contact with aircraft operating on taxiways and runways cannot be established or maintained and • instruct pilots to provide accurate position reports to aid the controller in determining an aircraft’s location in such conditions.
TO THE FEDERAL AVIATION ADMINISTRATION: Brief all air traffic controllers about the circumstances of this incident, emphasizing the effect that certain conditions might have on a pilot’s ability to begin a takeoff in a timely manner, including • low-visibility weather conditions, such as fog; • ambient conditions, such as temperature; and • surface conditions, such as ice, snow, and other precipitation, as noted in Order 7110.65, Air Traffic Control, paragraph 5-8-4, Departure and Arrival.
TO THE FEDERAL AVIATION ADMINISTRATION: Amend the Aeronautical Information Manual so that it instructs pilots to inform controllers, before entering an active runway with the intent to depart, when they need time on the runway for any reason before beginning the takeoff roll.
TO THE FEDERAL AVIATION ADMINISTRATION: Require all airports with a Surface Movement Guidance and Control System plan to ensure that their plans and the associated letters of agreement correspond with each other and the stakeholder duties and responsibilities described in Advisory Circular 120-57, Surface Movement Guidance and Control System.
TO THE FEDERAL AVIATION ADMINISTRATION: Direct training administrators at airports with a Surface Movement Guidance and Control System plan to require initial and annual refresher training for all stakeholders, including air traffic controllers and airport operations personnel, on the information in the airport’s plan.
TO THE FEDERAL AVIATION ADMINISTRATION: Require training administrators at all operating air traffic control towers to conduct annual refresher training on low-visibility operations.
Sequence of events
3 timed eventsfrom the FDR factual report · claude-sonnet-5- 06:30 CSTIncidentp.3Incident occurred involving Airplane 1 (FedEx Boeing 767-300) and Airplane 2 (Southwest Boeing 737-700) at Austin, Texas
- 06:39:00 to 06:42:00 CSTIncidentp.6Time window designated as "Incident" period for FDR data plots and tables
- Unspecified (dashed line reference time)Go-aroundp.6Initiation of the go-around by Airplane 1 (FedEx), shown as a dashed line reference on each figure
NTSB analysis
from the final reportOn February 4, 2023, about 0640 central standard time, Southwest Airlines (SWA) flight 708, a Boeing 737-700, N7827A, and Federal Express Corporation (FedEx) flight 1432, a Boeing 767-300, N297FE, were involved in a runway incursion at Austin Bergstrom International Airport (AUS), Austin, Texas. The flight crew of the FedEx airplane, which was arriving on runway 18L, executed a missed approach as the SWA airplane was departing from the same runway. The 128 occupants aboard the SWA airplane and the 3 occupants aboard the FedEx airplane were not injured, and neither airplane sustained damage. SWA flight 708 was a regularly scheduled international passenger flight operating under Title 14 Code of Federal Regulations (CFR) Part 121 from AUS to Cancún International Airport (CUN), Cancún, Mexico. FedEx flight 1432 was a domestic cargo flight operating under Part 121 from Memphis International Airport (MEM), Memphis, Tennessee, to AUS. Night instrument meteorological conditions prevailed at the time of the incident.