Two commercial airplanes nearly collided after takeoff from George Bush Intercontinental Airport in Houston on Dec. 18, prompting a federal investigation into the incident and the actions of the flight crews and air traffic controllers involved.
The Federal Aviation Administration said the incident involved two separate passenger flights that departed the airport on the same day under the control of Houston air traffic controllers.
The FAA said one of the aircraft reportedly deviated from instructions issued by air traffic control shortly after departure.
The agency said the deviation led to a loss of standard separation between the two planes as they climbed away from the airport.
The FAA said radar data and audio recordings captured the sequence of events between the departing flights and the control tower.
The FAA opened a formal investigation to determine how close the aircraft came to each other, what caused the reported deviation from instructions, and whether any regulations were violated.
Investigators are reviewing communication transcripts between pilots and controllers, radar tracking information, flight data, and cockpit voice recordings where available.
The FAA said it will examine whether the flight path of the plane that reportedly deviated matched the clearance issued by air traffic control before takeoff.
The National Transportation Safety Board has the authority to join or lead an investigation when a serious risk to aviation safety occurs, but the NTSB has not publicly announced its own separate investigation in this case.
Both airlines involved in the incident have been notified of the federal review and have access to preliminary information through standard safety reporting channels.
Bush Intercontinental is one of the busiest airports in Texas and handles a high volume of domestic and international flights each day.