The Federal Aviation Administration has launched an investigation into a collision on a United Airlines flight that injured two passengers after pilots warned the plane of a mid-air collision.
United Airlines says Flight 2428 from Newark, New Jersey, was landing at San Francisco International Airport last Thursday when it “slowed down due to another aircraft at a lower altitude.” United said in a statement that both injured passengers were taken to a hospital.
An FAA incident report said one passenger suffered serious injuries and another suffered minor injuries last Thursday when pilots responded to a traffic collision avoidance system resolution advisory, or “TCAS RA.”
Collision avoidance advisories are considered extreme warnings of a potential collision with another airplane and require pilots to take immediate action.
Data from FlightRadar24 shows the incident occurred at an altitude of 31,000 feet as the flight neared Lake Berryessa, about 70 miles north of San Francisco. FlightRadar24 says the Southwest Airlines flight was 3,000 feet below the United flight and the SkyWest flight was 1,000 feet below.
The FAA — which is responsible for regulating air traffic — said in a statement that “there appeared to be no impairment of safe separation.”
In audio obtained by LiveATC.net, the pilots can be heard declaring a medical emergency, telling air traffic controllers in Oakland that “someone broke his ankle and when we took the RA, some passengers were hurt.”
United Airlines told CNN that the seatbelt sign was lit at the time of the incident and one of the injured passengers was out of his seat.
The National Transportation Safety Board has not yet launched an investigation, but a spokesperson told CNN the agency is gathering preliminary information.
Thursday's in-flight incident is the latest this month to involve a possible collision. On Sept. 12, an Alaska Airlines flight was forced to abort its takeoff in Nashville because a Southwest flight was crossing the same runway. Two days earlier, the wingtip of a Delta Air Lines Airbus A350 struck a smaller regional jet while the two planes were taxiing, causing the regional jet's rear to collapse.
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