The Federal Aviation Administration has opened an investigation into the jolt of a United Airlines flight that injured two passengers when the pilots responded to an on-board warning of a mid-air collision system.
United Airlines says that when flight 2428 from Newark, New Jersey, descended into San Francisco International Airport last Thursday, it “slowed its descent to accommodate another aircraft at a lower altitude.” Both injured passengers were taken to the hospital, United said in a statement.
An FAA incident report says one passenger suffered serious injuries and another suffered minor injuries Thursday when pilots responded to a advisory to avoid traffic collisions or “TCAS RA.”
Collision resolution messages are treated as extreme warnings of a possible collision with another aircraft and pilots must act immediately.
Data from FlightRadar24 shows the incident took place at 31,000 feet when the flight was near Lake Berryessa, about 70 miles north of San Francisco. FlightRadar24 says a Southwest Airlines flight was 3,000 feet below the United flight and a SkyWest flight was 1,000 feet below.
In a statement, the FAA — which is responsible for controlling air traffic — said “there was no loss of safe separation.”
Audio from LiveATC.net captured the pilots declaring a medical emergency, telling air traffic controllers in Oakland that “someone may have broken an ankle and there are passengers who were injured when we had an RA.”
United Airlines told CNN that the seat belt sign was on at the time of the incident and that one of the injured passengers was out of their seat.
The National Transportation Safety Board has not yet opened an investigation, but a spokesperson told CNN that the agency is gathering preliminary information.
Thursday’s in-flight incident is the latest incident involving a possible near-miss this month. On September 12, a flight with Alaska Airlines was forced abort its start in Nashville due to a Southwest flight crossing the same runway. Two days before, the wingtip of a Delta Air Lines Airbus A350 hit a smaller regional jet while both planes taxied, causing the regional jet’s tail to fall off.
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