Investigation Summary
The accident was primarily driven by a loss of situational awareness by the local controller, Robin Wascher. During a period of high workload and equipment limitations, Wascher cleared SkyWest 5569 to 'taxi into position and hold' at intersection 45 on Runway 24L. Shortly after, she cleared USAir 1493 to land on the same runway. The Metroliner's position at an intersection, combined with glare from terminal lights and the lack of functioning ground radar, made it nearly invisible to both the controller and the USAir crew. The 737 landed directly on top of the Metroliner, crushing it. The wreckage slid into an abandoned fire station, where a fire erupted, fueled by the Metroliner's fuel and the 737's oxygen system. Evacuation was hampered by smoke and jammed exits, leading to many fatalities from smoke inhalation.
Final Conclusions
The NTSB determined the probable cause was the failure of Los Angeles Air Traffic Facility Management to implement redundant procedures and the FAA's failure to provide adequate oversight. These systemic failures created an environment where a single controller's loss of situational awareness led to inappropriate clearances. Contributing factors included the lack of functioning ground radar (ASDE) and poor visibility of small aircraft against airport background lighting. The NTSB also noted that deficiencies in the controller's performance were apparent in the accident sequence, specifically her loss of situational awareness and aircraft misidentification.
Photographic Evidence (1)
Video Analysis
Runway Collision of USAir Flight 1493 and SkyWest Flight 5569 — Analysis of the 1991 ground collision at LAX involving a Boeing 737 and a Fairchild Metroliner. The video examines air traffic control errors and visibility issues that led to the disaster.
If playback is blocked, the owner has disabled embedding — use the link above.
Crew Experience
Captain
Killed in the collision due to blunt force trauma.
First Officer
Survived and was rescued through the cockpit window.
Captain
First Officer
Systems & Failure Modes
ASDE (Airport Surface Detection Equipment)
Ground radar intended to help controllers track aircraft on runways and taxiways; it was inoperative during the accident.
Crew Oxygen System
Damage to the 737's oxygen system released gaseous oxygen, which intensified the post-crash fire in the forward cabin.
Interesting Facts
- 01The ground radar (ASDE) at LAX was out of service for maintenance at the time of the accident.
- 02The local controller was distracted by a missing flight progress strip for another aircraft (Wings West 5006).
- 0317 of the 23 fatalities on the USAir flight were found to have died from smoke inhalation after unbuckling their seatbelts.
- 04The SkyWest Metroliner did not have a Cockpit Voice Recorder or Flight Data Recorder, as they were not required for that aircraft type at the time.
- 05Billionaire David Koch was one of the survivors of the USAir flight.
Safety Actions & Advisories
Runway Segregation
LAX moved toward segregating runways, prioritizing outboard runways for landings and inboard runways for takeoffs to reduce intersection conflicts.
Improved Tower Visibility
A new, taller control tower was constructed at LAX to provide controllers with a better vantage point of all runways and taxiways.
Aircraft Flammability Standards
The FAA accelerated requirements for upgrading the flammability standards of cabin materials to improve passenger survival time during fires.