The FAA said it has increased safety oversight of Southwest Airlines to ensure that the carrier is complying with federal safety regulations.
The move follows a series of recent incidents, including a July 14 flight into Tampa that had an unusually low approach. The plane was flying as low as 150 feet from the ground while 4.8 miles from the runway, when the pilot was alerted by an air traffic controller, the FAA said. Previous flights headed toward the same runway were flying at 1,200 feet at the same point, according to Flightradar24.
The FAA also is investigating a June 19 flight that descended too low while 9 miles away from Oklahoma City Airport. A controller alerted the Southwest pilot on this flight, as well.
In addition, regulators are investigating a June 25 flight in which Southwest took off from a closed runway in Portland, Maine, and a May 25 incident in which a Southwest flight traveling from Phoenix to Oakland did a Dutch roll.
In a statement, Southwest said it is working closely with the FAA in the agency's review of recent events.